ood extracti n ith oxen

an agricultural tractors

f

Wood extraction with oxen and agricultural tractors

by E. Otavo Rodriguez Andre Mayer Fellow

The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country. territory. city or area or of its authorities. or concerning the delimitation of its frontiers or boundaries.

M-30 ISBN 92-5-102129-5

All rights reserved. No part of this publication may be reproduced. stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying or otherwise, without the prior permislion of the copyright owner. Applications for such permi.sion. with a statement of the purpose and extent of the reproduction, should be addressed to the Director, Publications Division, Food and Agriculture Oru-nization of the United Nations, Via delle Terme di Caracalla, 00100 Rome, Italy.

© FAO 1986

- iii -

PREFACE

The FAO Forestry Department haa long reoognized the importanoe of intermediate teohnology as a development tool. The uee of animals and agricultural tractors with forestry acoessories is an example, expanding the possibilitieB of both. Traditional agrioulture and forestry complement each other.

The use of animalB or small agrioultural tractors with simple acoessorieB for log­ging also oonstitutes a means of saving imported fuel. The logger oan attain good levels of produotion at sufficiently low cost to enable him to meet the needs of both rural and other markets.

Two methods of logging whioh oould be good alternatives for developing countries are desoribed in thiB report, based on a study made in 1983 under the Andr6 M~er Researoh Fellowship Programme.

Through this programme, FAO can oontinue to offer useful alternatives to conven­tional systems and, at the Bame time, provide the right training for young people in developing countries.

M. A. Flores Rodas

Assistant Director-General

Forestry Department

- v -

SUMMARY

This study was undertaken main~ in order to demonstrate the use of oxen to skid logs in plantation and natural forests. Skidding with an agricultural tractor was also studied so that the output and costs of both methods might be oompared. Researoh was oonduoted in regions of Chile where oxen have traditional~ been used in forestry opera­tions. It was found that forest enterprises with a high degree of technical abilities were using oxen to obtain their supplies of raw materials, reaching exoellent levels of produotion with them. Their use led to savinJs in fossil fuel and generated employment. The equipment needed was simple and easily available.

The conclusions drawn were that oxen oould be used with positive reeults in both plantation forests where there is olear felling or thinning, and in natural forests where there il seleotive extraction, whether on level ground or on Iteep slopes. When the oosts of oxen were compared with those of agrioultural tractors, it appeared that animals were more eoonomic.

As well 88 a description of the methodology employed in the study, and the results, some general information is provided on oxen in forestry work, including morphological oharacteristios, the commonest diseases that oan be diagnosed qy the ox-driver, feeding, and the equipment and techniques used.

- vii -

ACKNOWLEDGEMENTS

The Food and Agrioulture Organization of the United Nations vi shes to thank all those per,ons and institutiona that provided faoilities, aupport and apeoial aBsiatanoe to the author in the preparation of thia atudy, and in partioular the following:

Patrioio Car~ Brionea, Profeasor of Foreat Utilization, Faoulty of Foreat Soiencea, Universidad Austral, Chile

Aoademio staff and seoretaries at the Institute of Forest Management, Faoulty of Foreat Scienoes, Universidad Austral

National Institute for Renewable Natural Resources and the Environment (INDERENA), Colombia

-ix-

tOLl 0' COftM'B

PRErM:E

Pap

11i

SlJIOURT

AC1CIOiLIDGDIDTS

IJITllODOOTION

f!!:Ll JACIDROOND

v

vii

1.1

1.2

General upeota of foreatZ7 in Chile 4 4 4 6

Geographioal aituation General foreatry related. featurea Methoda aDd implell18Jlta uaed.

Kethoclology uaed. in the at~ 7 7

7 7

1.2.1 Eatimating tim ..

1.2.2

1.2.3

1.2.1.1 Bormel time 1.2.1.2 Supplementary time

aj Supplement for faUgue b Supplement for personal need.a o Supplement for clel.,.

Deaoription of movement a

1.2.2.1 Trip without load 1.2.2.2 Loading 1.2.2.3 Trip with load 1.2.2.4 Unloading

Detemining Um"

1.2.3.1 Time per work oyole 1,2.3.2 Time per m3

Detemining output Coata per unit of volume

1.2.5.1 Variablea applied to cletemine the ooat of akidding with oxen

a) lI'ixed. ooata

Intlrest, depreciation, teed, medioal aDd

8 8 8

8

9 9 9 9 9 9

10

10 10

11

11

veteriJW'1 aerrioe, ooat ot mortallt, 11-12

b) Variable ceat. 12

Special feed, labour 12

1.2.5.2 Variable. applied to d.eternd.ne the 008t of akidding with agricultural tnot01'll 13

a) r1xed ceata 13

Intereat, d.epreciation, lioenoe 13-14

b) Variable ceata 14

Repa11'11, Urn, fuel, lubrioaat., tUte1'll and. lJZ'UIe, lOOeaaol'J equiPMIlt, IM1ntenaoe, labour 14-15

- x -

1.3 General oonditione of the study

~ SKIDDING WITH OXEN

2.1

2.6

Draught animals throughout the world

Skidding with draught animals

2.2.1 Skidding with oxen

General information on oxen as draught animals

2.3.1 Advantages and UBeB 2.3.2 Morphological oharacteristios 2.3.3 Castration, training and handling 2.3.4 Load oapacity 2.3.5 Pull Btrength, tractive effort and power 2.3.6 Feed and energy

2.3.6.1 Feeding prinoiples 2.3.6.2 Energy requirements

2.3.1 HYgiene and diseases

2.3.1.1 Skin diseases

ab

) Tioks ) Pedioulosis

c) Ringworm d) Warh

2.3.1.2 Hoof problems

a) AbBceBseB b) Hoof rot c) Stones in the hooves

2.3.1.3 Ooular diBordere

a) Foreign bodieB in the eye b) Infectious keratitis (pink eye)

Skidding equipment and harness

2.4.1 Description

2.4.1.1 Double head yoke 2.4.1.2 Yoking straps 2.4.1.3 Chaine

e.) Chain with hooks b) Chain with olamps

2.4.1.4 Goad

2.4.2 Harnessing the oxen

Skidding technique

2.5.1 Felling and its influence 2.;.2 Arrangement of the load 2.5.3 Paths

Methodology of stUdies of skidding with oxen 2.6.1 Skidding in Ndi.t. pine pllmuUODII

2.6.1.1 Ski44ing 1n elapine are .. Reaulte, lD&l.;reiB ad. diBOUlle1on

Page

15

18

19 19

19 19 21 22 23 24 25

25 26

28

28

28 28 28 29

29

29 29 29

29

29 29

30

30

30 31 31

31 32

33

33 33

33 34 35

35 36 36

37

- xi -

a) Speed and load

b:l Time Output Coata

2.6.1.2 Skidding on level Iround

Relults, &nalyais and dilousaion

a) Speed and load

b) Time

0) Output

d) COlts

2.6.2 Skidding in natural foreat

2.6.2.1 Conditions of the ItUdy

RelultB, analyaia and diBcusBion

a) Speed and load

b) Time

c) Output

d) COBte

Part 3 SKIDDING WITH AGRICULTURAL TRACTORS

Bacqround

Conditions of the study

Teohnical Characteristios of the tractor

3.3.1 ntmensions and oapabilities 3~3;2- l1li111. 3.3.3 Tir .. 3.3.4 Hydraulio IYltam 3.3.5 Power take-off 3.3.6 Winoh

Results, analylis and disoussion

3.4.1 Speed and load 3.4.2 Time 3.4.3 Output 3.4.4 COlte

~ONCLUSIONS AND RECOMMENDATIONS

Appendix 1 A. CLASSIFICATION OF TYPES OF CHILEAN NATURAL FOREST B. PRINCIPAL Tm SPmIIB IN AREAS STUDID

Appendix 2 FORM US'ED FOR FIELD DATA COLLlIX:TIOlf IN THE TIME STUDY

Appendix 3 DJr1'IRMINING COSTS IN SKIDDING WITH OXEN

Appendix 4 A. SKIDDING WITH HORSES B. EQUIPMENT USED IN SKIDDING WITH HORSES

Appendix 5 TABLES FOR TUIE VALUES, COSTS AND OUTPUT

Appendix 6 lBl'IRMINING COSTS !If SKIDDING WITH AGRICULTURAL TRACTORS

BIBLIOGRAPHY

Pace

37 38 42 44

47 48

48 48

50 52 53 56 57 57 57 58 59

62

62

63 63 63 63 63 63 63 65 65 65 66 67

69

71

73

74 76 79 81

89 91

- xii -

LIST OF TABLES

1. Approximate area of forest plantations

2. Estimated draUSht capacity of oxen with drawn implements at low and averBle working speeds

3. Eetimated TDN needs of oxen of various aizes working at different rates

Pace

25

for 4, 6 and 8-hour periods 27

4. Averace speed and load in units and volume per degree of gradient in skidding loga and pulpwood with oxen 37

5. Time equations per work oyole in skidding aawlogs and pulpwood with oxen by d8irees of slope 38

6. Time equations per m3 in skidding sawlogs and pulpwood with oxen, b,y degrees of alope 38

7. Output equations in skidding aawlo,. and pulpwood with oxen, by d8irees of slope 43

8. COlt equations per m3 in Ikidding lawlogs and pulpwood with oxen 45

9. Average speed and load in units and volume, in skidding sawlog. and pulpwood with oxen on level ground with different felling systems 48

10. Time equations per work oycle and per m3 in skidding sawlogs and pulpwood with oxen on level ground with different felling systems 49

11. Output equations in skidding sawlogs and pulpwood with oxen on level ground with different felling systems 51

12. Cost equations per m3 in skiddiUC saw logs and pulpwood with oxen on level ground with different felling systems 53

13. Averace load in units and volume b,y degrees of gradient in skidding sawlogs and pulpwood with horses 77

14. Time equations per m3 and output in m3/h in skidding sa1l10gs and pulpwood lIith horses on sloping ground, using chains 78

15. Time values per lIork oycle, per .3; and output according to distanoe and slope in skidding sawlogs with oxen in radiata pine plantations 81

16. Cost per m3 according to distance and slope in skidding sa1l10gs lIith oxen in radiata pine plantatiOns 82

17. Time values per work cyole, per m3; and output according to distance and slope in skidding pulpwood lIith oxen in radiata pine plantations 83

18. Costs per m3 according to distance and slope in skidding pulpllood lIith oxen in radiata pine plantations 84

19. Time values per 1I0rk cyole, per m3; and output aooording to distance in skidding sawlOis and pulpwood with oxen on level ground in radiata pine plantatiOns 85

20. Cost per m3 acoording to distance in skidding s&1l1088 and pulpwood with oxen over level ground in radiata pine plantations 86

21. Time values per work oyole and per m3; output; and cost per .3 acoording to distanoe on slopes of -20 to -32 percent, for skidding with oxen in natural for .. t 87

22. Time values per work oyole and per .3; output; and COlt per m3, in skidding' with an acrioultural traotor on slopes of +0.15 to +9.38 peroent 88

- xiii -

LIST OF FIGURES t MAPS AND DRAWINGS

Page

1. Map of the Republic of Chile and mapa showing its location in South Amerioa and its forested areas 5

2. Movements in skidding oycles 8 3. Principal morphologioal parts of a draught ox 21

4. Double head yoke for skidding oxen 30

5. Chain with hooks for skidding with oxen 32 6. Chain with olampa for transporting large-cii8llleter logs 32

7. Goad to guide and drive oxen 33 8. Time in minutes per work cycle to .kid .... 10811 with oxen all

different degrees of slope 39 9. Time in minutes per work oyole to skid pulpwood with oxen on different

degrees of slope 40

10. Time in minutes per m3 to skid sawlogs with oxen on different degrees of slope 41

11. Time in minutes per m3 to skid pulpwood with oxen on different degrees of slope 42

12. Output in m3jh in skidding sawlogs with oxen on different degrees of slope 43

13. Output in m3/h to skid pulpwood with oxen on different degrees of slope 44

14. Cost per m3 in skidding with oxen in relation to slope and distanoe 46

15. Cost per m3 to skid pulpwood with oxen in relation to slope and diBtanoe 47

16. Time in minutes per work cycle to skid sawlogs and pulpwood with oxen on level ground 49

17. Time in minutes per m3 to skid sawlogs and pulpwood with oxen on level ground 50

18. Output in m3/h in skidding sawlogs and pulpwood with oxen on level ground 51

19. Cost per m3 in skiddin, sawlogs and pulpwood with oxen on level ground 52

20. Profile of a path for oxen skidding in natural forest 54 21. Time in minutes per work cyole and per ~3 for skidding with oxen in

natural forest on slopes of -20 to -3~ peroent 58 22. Output in m3jh for skidding with oxen in natural forest on slopes of

-20 to -32 percent 59 23. Cost per m3 to skid with oxen in natural forest on slopes of

-20 to -32 peroent 60 24. Time in minutes per work oyole and per m3 to skid with an

BBrioultural tractor on slopes of +0.15 to +9.38 peroent 66 25. Output in m3jh to skid with an agrioultural tractor on elopes

of +0.15 to +9.38 peroent 67

26. Cost per m3 to skid with an BBrioultural tractor on slopes at +0.15 to +9.38 peroent 68

27. Draught horse for skiddiIIB, with harness and hauling ~ipment 76

- xiv -

28. Ti.e in minutee per .3 in akidding eawlog. and pulpwood with horae. on eloping ground

29. Output in a3/h in akidding .awloge and pulpwood with horaea on eloping ground

30. roa.iacen trailer

31. VB! (Varmaland! Sko,aarbeteatudier) eledge

32. Doa1nBaxen akidding tonga

P~e

77

78 79 ~

~

-ZT-

Ox-4rawn cart ina .aWllli 11

'anUl.l lateral louing of 1081 in I. l'I4ia. pine for .. t

Pile of pulpwootl 'boltl 1.J'I'&nged. in l'\&ok metree

Skidding with O:E8n in pllntation toreetl

Skidding wi th a hONe and wi th ozen in a Ndiata pj ne foreet

UI:! nl ozen to tranlport toreet produotl OD nUs

U.ing oxen for lateral loading of 1081 in plantation for .. ts

Usi ng YOllftg oxen to draw cart. in a sa1lllllill

Skidding with oxen in a miata pine forest

Oxen wi th double head yoke

'l'eam of oxen harnl!ls.ed with skidding equipment

Controlled felling and divi.ion of the area into stripe

'!'hin loge arranged in piles

Skidding with ox.n in natural fore."', using the work-sharing eyt!ltem

Log .kidded by the work-.haring method, with ohaine 1d. th hOOD attached to the front

Skidding with oxen in natural fore.t

Skidding with an asr10ultural tractor and winch

'l'ranaportiJIB loge with an asr10ultural tractor and trailer

Skidding with an agrioultural tractor ul1ng the upper pulley of the winch

Skidding with an asr10ultural tractor, USing the winch drwn

3 ;

12

17

18

20

20

23 24

31 33 34

35

55

55 56 61

62

INTRODUCTION

In the foreetr,y enterprises of many oountries to~ high~ meohani.ed systems are used to extract wood. Maohinee have replaced two of the traditional souroee of energy -hllllan power and animal power - and their use has meant that the simple teohnology and ekills of the paat have been lost.

Machines are expensive and energy-oonslllling. The prioe of the fuel that they re­quire rises oontinU&l~ and developing oountries often have to ~ for it in soarce foreign ourrenoy.

Draught animals, whioh have been used by man sinoe anoient times, provide a eolu­tion to the need for power and the advera. effects of the energy orieie and the oost of foesil fuel. Far from being a sign of technologioal backwardnlla, their use in foreetry oan signify the intelligent exploitation of a reaouroe whioh not only makea a useful oon­tribution in energy aaving, but also providea employment in a developing sector of the econolllJ'.

In this atudy of the uae of oxen for akidding in Chilean forests in 198), oompari­aon is made with the use of an agrioultural tractor.

It ia divided into four parte. The firet outlines various general aspeota of for­eatr,y in Chile, and d .. oribea the methodology used in the atudy and the oonditions in whioh reaearoh was oarried out. The aeoond part deala with akidding with oxen, the ani­mala' morphological oharacteriatioa, tractive power, reeding, hygiene and dileas .. ; the equipment and teohniquea used, and last~, the use of oxen in forest. of Pinus radiata ~ (insignia pine, radiata pine) and in natural foreata; with an ana~aia of time. per work oyole, output and ooata. Part) oonoerns aJCidding with an ABrioultural tractor in radiata pine forest, giving comparable ana~ ... of timea, output and ooat.. Conclusions and reoommendations are pre .. nted in Part 4.

It ia hoped that the atudy will prove useful in oountriea where poaaibilitiea of inveatment are low and unemployment ia a aooioeoonomio problem. It ahould offer luch oountriel aome alternativea to akidding ay.tama whioh are not profitable and help them to ohoole the beat one in the light of their prioritiel, whioh are: eoonolllJ', productivity, energy-eaving and full employment.

The author, Edgar Otavo Rodrigue., is a foreater working on the Project for Control and Review of Foreat Utilisation in Bajo Atrato-Uraba, under the National Inatitute for Renewable Natural Reaouroee and the Environment (INDERENA) in the Republio of Colombia.

- 3 -

Ox-drawn oart in a eawmill (Lee Sauoes, Chile)

- 4 -

1 .1 GENERAL ASPIOTS OF FORESTRY IN CHILE

1.1.1 aeographioal.ituation

The Republio ot Chile i. on the .outhw .. t ooaat ot South Amerioa, between lati­tude 17030' and 900S and 10llBitud .. 66030' and 75040'W. It is ru&Bed and mounhinous, with not more than 20 peroent ot tlat land. The three oharacteristio morpholoBioal features are: .ountain r&JIBe. of the And .. oordillera on the eaat, the ooaatal mountain r&JIBe on the we.t, and lowlandl between the.e two. The average width of the oountry i. 177 len and it. length from the northern limit to Cape Horn is around 4200 Ian.

1.1.2 General fore.tr,-related features o 0

The major forest area mad. approximately from 33 to 34 s, u far u the i.land of Chilo'. Within thi. area, rainfall OM vary depelllting on the topography, from le •• tliID 1 000 mm in the valley to more than 5 000 mm in the mount&1na of the south (Weber, 1957).

The oold Humboldt Current, running from the South Pole to the equator, influences all the major forest areu in Chile and prevente temperatur .. from rising.

Moet of the foreet plMtatione are in the oentral southern area of the oountry and oover approximately 877 186 ha. They are oomposed mainly of radiata pine, euoalyptue, tamarugo and other epeche (.ee Table 1).

Table 1

APPR01IIW'E .AREl 011' lIORI8T PLAIPl'ATION

Species Area (ha) ".

Radiata pine 786 136 89.6

EuoalyptUII 40 800 4.6

Tamarugo 16 500 1.9 Oregon pine 8 900 1.0

Poplar 3400 0.4

Algarrobo 3 150 0.4

other speoie. 18 300 2.1

TOTAL 877 186 100.0

Souroe: CONAF: INFOR (1983)

Chile'. natural forest .tretohes from the oentral area (3~S) to the south over the .lope. ot the And .. Md the ooaatal r&ll8e, ooverins the oentral valley partially or total~. The area i ... timated at 7 616 500 ha, with an approximate volume of 984 mil­lion m (CONAF, 1983).

- 5 -

, . .. c

>

.... 0

." • \ ...

z

'" OJ

co a:

••• e

-.-I.J

~ .1· i.:: ,( t .,' \ ,.. l

:-' \

n· (".-1 .COPtAPO

~ ! ... ~ III

U r' I;)

f ... /'

,.,.~

..,. .,

...

...

...

... c z

•• .. z ... ... 0

a: C

to- ...... ...

Figure 1. MAP OP 'ME REPUBLIC OP CHILE All]) MAPS SJI01fDlO ITS LOOA'l'IOI III SOO'l'H AMERICA AJI]) ITS J'OREB'fED ARIAS

- 6 -

There are more than 60 tree and ehrub speoiea, mainly broad-leaved, of whioh aome 20 are used for produotion of aawDWood, veneera, boards and other eoonomioally im­portant produota. The dominant speoies have been used by Donoao (1981) to olasaify 12 foreat types, made up of mixed atands (aee Appendix 1).

Evergreen ia the moat extenaive and oomplex foreet type beoauae of ita floriltic variety and the eoonomio value of some high-quality apecies, and becauae there are still relatively well oonaerved foreat areas (Paredea, 1981).

The most marketed apeciee are poplar, alero~, aromo, oyprele, ooigue, euoalyptus, laurel, lingue, luma, m.nlo, olivillo, arauoaria pine, Oregon pine, radiata pine, raul!, roble, tepa, tineo and ulmo.

The foreetry seotor plays a major role in the oountry's economy, being the eeo­ond largest foreign currenoy earner. Acoording to CONAF and INFOR (1983) the main export produots in order of importance are: pulp (bleached, unbleached and semi-bleached)j saWD wood (radiata pine and other speoies): loga (radiata pine and other apeoiea)j neweprintj veneera and wood based panels (particle boar4, fibre board, pl1Wood, blook board)j fine oardboard for punoh carde, sUlphite paper, kraft paper, c~llophane paper, aluminium paper, other papers and cardboard,jother minor export produots (blinds and Ihuttera, roofing IhiDilel, radiata pine rOlin, furniture, brush handlel t matchwood, other procelled wood products, radiata pine leeds, tOYl, poStl and charcoal).

The apeciea exported are, in order of importance: radiata pine, raul!, tepa, alerOl,lenga, laurel, eucalyptus, radal, araucaria pine, roble, man! 0 , Oregon pine, ulmo, aromo and tineo (CONAF and INFOR, 1983).

Methode and implements used

Primary logging activitiel are carried out mainly with chainsawa, axel and hand-lawa.

Practically all felling and cutting into loga in foreat pl&ltations ia done with chainaawa, and debranching with axea. The work ie done by teama of four to eix people, one of whom operatee the chainsaw while the othere aseiat him by lopping off branchea.

The toola uaed for theae activitiea in natural foreata are the ohainaaw, the axe and, in lome casea, the corvina (orolecut law). The teama for felling and lawing loga are made up of two workera, poaaibly one with a ohainaaw and the other with an axe, or both with hand-eaw and axe.

Skidding il usually done with oxen, horeea, wheeled and crawler tractora, wheeled artioulated tractors, agricultural tractora with or without logging equipment, Qr cablea. The choice of method depends on topographical oonditiona and how the worK ia organized.

Skidding diltancea are variable and depend on the planning of the work and on the type of forest. In plantation foreatl the diatance for haulage with oxen ia between 50 and 100 m, and with tractora between 400 and 600 mj in natural foreate, the akidding diatanoe with oxen can be as much aa 1 ;00 m, and with wheeled or orawler tractora an average of 800 to 1 000 m.

- 7 -

Manual lateral loading of logs in a radiata pine forest, San Ignacio de Palomares

Long-distanoe transport is almost exclusively by truok or rail. Loading and unloading are manual, with hydraulio oranes and frontal loaders. Manual loading and un­loading are important in handling pulpwood and saw logs • In natural forests, musole power is supplemented by temporary loading ramps.

1 .2 METHODOLOGY USED INI'HE STUDY

The methodology developed for this study was similar for skidding both by oxen and by traotors as regards oaloulating times, movements and output. It varied in the oaloulation of oosts and wagesj the latter have therefore been described separately.

1.2.1 Estimating times

For eaoh work cyole, an estimate was made of the time involved in the movementa in skidding operationa, inoluding normal and supplementar,y times.

1.2.1.1 Normal time

This is defined as the time neoessary to oarry out one aotivity in the work oycle.

1.2.1.2 Supplementary time

Alao known as additional time, this is any time lost in del~s or interruptiona in the work. The subdivision of this time vari .. aocording to different authorsj this study was based on subdivisions made qy Cardiel (1974) and FAO (1970), namely: supplement for fatigue, supplement tor personal needs and supplement for del8¥s.

- 8 -

a' Supplemlnt for fati,uI

Thi. w .. thl re.t period taken Qy the oX-driver or the workerl in order to re­oovlr from the wearin"l oauaed b7 thl work. It W&l time for relaxation, drinking water in dry weather or warming thl hands when it i. oold. It did not inoludl time .pent in eating.

It al.o inoluded time for thl oXln to reet during .kidding when nloe •• ary, but did not inolude thlir middaJ break.

b) Supplement for personal nelds

Thi. W&l the time .pent ~ fore.t worker. on their ~iololioal needs -ohanging olothe., among othlr thin,e.

0) Supplement for del.,.

Time •• pent on dll~. m~ or m~ not be oomputable. The first oaee oovered in­oidental del~. during .kidding, .uoh &I: reoeiving work instruotions, .etting up equip­ment on the work.ite, preparing tractor. or ox-team. in the .kidding area, changing parts or .parl part., removing ob.tacleB whioh made movement diffioult over the lkidding pathl, pioking up branohe" putting in petrol, adju.ting the ohain or the oable if it broke, ,ettling or re.tacking the load at the ,tart of the trip, Bettling and rearranging the oxen'B harne., when it sot out of place. Some driver, al.o allowed the oxen to pauae when the animal, relieved their phy.iologioal needs; this time was therefore conaidered oomputable.

Among non-oomputable del~. m~ be mentioned acoidental or unneoe,Bary 10lBel of time, inoluding: fors.tting tool., oonverlations between the workera, and all del~B out­'ide the normal proa.... Theae time. were not oomputed in the BtUdy.

Computable supplementary tim. wal totall.d and diltributed proportionately to each work oyole, .ince it was oonsidered as an integral part of a working daJ and not of a ,pecifio or partioular oyole.

1.2.2 DeBoription of movem.nt.

Th. movement. oon.idered in the work oyol .. wire: trip without load, loading, trip with load, and unloading. The.e phase. have been mentioned by various reeearoh workerl in .tudiel of .kidding time; &mong other., An&¥a (1975), Bezada and Fri.k (1980), and C6rdova and Fri.k (1979). Fig. 2 illustrate. the ItBBeB of the oyole.

1. Tr~p without load 2. Loading 3. Trip with load 4. Unloading

Pll. 2. IOVIMIB'lI III SIDDIJIQ CTCLBS

- 9 -

1.2.2.1 Trip without load

Thil WBa d.fined Ba the time Ipent by the traotor or the ox.n when th~ oovered, without a load, the diltanoe from the landing to the plaoe where the load Wal pioked up.

1.2.2.2 Loadinc

Thil was the time reoorded from the DloDlent the team of oxen or the tr8Otor ar­rived at the pl80e where the logl were, until the moment it left. It inoluded manoeuver­illl the oxen or the traotor to talce up the load, arrqing the logl and fastening them, but not the time Ipent on It80king the load, linoe this work WBa done qy workerl other than the driver.

1.2.2.3 Trip with load

Thil oovered the time of transportation from the moment the traotor or team of oxen started to move with the load from the loading area until it arrived at the landing.

1.2.2.4 Unloadinc

Thil was the time from the moment the traotor or the oxen reaohed the landing to deliver the load until the ohain or oable was fully reoovered and remained on the yoke or the winoh, as the oase m8¥ be.

Some researoh workers put the above timee in two groups: terminal and variable times.

Terminal times are those that tend to be constant whatever the skidding distanoe: they inolude loading and unloading.

~ariable times are those that depend on the diltanoe to be oovered and the gradient of <the paths. They inolude trips with and without load.

1.2.3 Determininc times

The IYltem used in measuring time is known as 'oycle reset' timing with return to zero, suggested by Morrow (1957) and ILO (1970). The time of e80h 80tivity in the skidding oyole was read and reoorded, the hands were returned to zero without stopping the cloak, and recording of the time of the subsequent aotivity immediately started. The information was taken on suooessive ~s on a prepared form (see Appendix 2).

The size of the s8lllple, namely, the number of oycles needed for the oases of skidding being studied, was determined statistioally and the respeotive equations were obtained later.

1.2.).1 Time per work cyole

This was defined as the total time spsnt per work oyole, inoluding oomputable supplementary times. The equations were obtained by the minim»m-equares method 11 fol­lowing the model t • a + bx, where:

t • time per work cycle, in oentiminutel (depend.nt variable)

a,b • ooeffioientl of the equation, terminal tt. .. x • diltanoe (independent variable).

11 Work oonduoted in the oomputer oentre of ths Univeraidad Austral of Valdivia, with the oollaboration of Mr. Raimundo Vega and Mr. Mario Meneses.

- 10 -

1.2.3.2 Time per .3

Thi. was the time needed to acoumulate 1 .3 of ti.ber at the landiDl, and it was obtained by relating the time per work oyole to the average volume of the load.

t a + b% · i . V-• Ume per .3 • Ume per work oyole, in oenUllinut ..

• average volume 01' load in m3

% • dietanoe.

1.2.4 Determininc output

output i. 8l:pres.ed in oubio metres per hour (m3/h) oaloulated on the basis of the relation between the average volume of load and the time per work cycle. For the purposes of oaloulation, the general and traditional formula used by An83a (1975), Cordova and Fri.k (1919) and other researoh workers was also used.

6000V o • -r-o • output, in .3/h

V • average volume of load, in.3

(6000 • oentillinute. in 1 hour).

Output oan also be asoertained using the following formula:

O. W T

Costs per unit of volume

These were caloulated as the quotient between the ooste per unit of time for the resouroes used (labour, oxen or tractor) and the production per unit of time (FAO, 1974).

The general formula u.ed waa: 3 Ch C(m) • -o

where: C(m3) • cost per 113

Ch • hourly cost of the resouroe.

o • output in 113/h.

By introducing the output CO) formulae equatiOns were obtained that could equally well be used to determine the oost. per 113, namely:

a) C{m3) Ch % t • 6000 V

Ch % '1' • 6000 b)

The hourly oost 01' .kiddilll with oxen oomprised the oo.t per hour of the team of oxen plus the labour, in this oase ~h. hourly oo.t of the driver.

The variabl .. in oaloulatilll the hourly oo.t 01' skidding with oxen and with an agrioultural tractor were difterent; th., have therefore been desoribed .eparately in this .tud3. Variable. were grouped in two ola .... for each oue .. ,'U84 OOlts and vari­able ooetl.

Pi%8d ooet. were thoee that were permanent even when there waa no produotion, such .. intere.t, depreciation, insurance, basio teed for the oxen, animal mortality and fi%ed wag ...

- 11 ~

Variable OOltl depended on the work (the operatione); tor example, OOlt ot tuel, replacement at tiree and speoial teed tor the oxen.

1.2.5.1 Variables applied to determine the oost of Skidding with oxen

This oost lIay be expreased as Ch . Cho + ChI

where: Ch . hourly oost of akidding

Cho. hourly oost of oxen

ChI. hourly cost at driver (labour).

a) Fixed oosts

Interest

This was oaloulated on the basia of the capital invested in bUTing a team of oxan, together with the purchase value of all the acoslloriea: oollar, yoking atrapa, hookl, yoke and goad.

Intereat is the sum paid for the ule at lIon~ on loan or, in a wider sense, it ia the return obtained tram a produotive investment of capital. For the purposes at oal­oulation, real interest in the case at Chile was considered to be 12 peroent.

I 1 (Va + Va) R IT 100

I (Va + VO}R 100 U

where: I oost of interest

Va. purohase value of acoeaaoriea

Va • purohase or breeding value of oxen

R . rate of interest (12 peroent)

U . hours of work per annum •

Depreoiation

Only ths acoesaories depreoiate'; the oxen did not lose their value, linoe at the end of their working life th~ were sold, providing meat for human oonsumption.

In thia study, depreciation is shown aeparately for metal elements ohain and hooks) and less durable elements (yoke, yoking straps and goad). will later be added together to give one oost.

where:

Va Cd • NU

Od. oost at depreoiation, per hour

I • useful life of accessories, in years

U • annual use, in hours.

(oollar, Their values

Oxen are usually ted on si1qe or ha,y when th~ are used for Ikidding; however, the type at feed can vary, so no tormula has been given tor obtaining this oost.

Medioal and veterinary lervice

The mon~ invested in medioal attention, medioines and vacoines was oonsidered to be 5 peroent of the purchase value of a team of oxen.

Gm • Va U x 0.05

- 12 -

whare r C.. .adioal oost. per hour

Vo. purohase or breading valua of a team of oxen

U • annual work in houri.

Coat of Mortality

Thia W&8 oaloulated at 5 peroent of the purohase prioe of a team of oxen, a per­oentaBe fraquent~ uaad in Chile Qy authore suoh .. Boto (1970). The value w .. obtained in the same Wa.Y .. the previoua O&8e.

b) Variable ooata

Speoial feed

Additional or Ipeoial feed w .. uaual~ given to oxen used for skidding. Basio information and the oaloulation of hourly oost oan be seen in Appendix 3.

This w .. the ~ent .ade to the driver for driving the oxen when skidding. It oovered only the waBes of one workman and did not inolude expenditure for people engaBed in staoking, since this w .. a different job.

The WaBeB of ox-driverB engaBed in skidding in Chile are very variable. It iB uaual to ~ by contraot or by piecework, fixing a epecific prioe which is usually quanti­fied in two wa.Ys: i) individual~, when the dimensions of the 10gB are on averaBe greater than 30 om in diameter and 2.50 m in length (aawlogs); ii) Qy staok metre 11 where manual piling is quick and e .. y. Reeearch oarrisd out by the author revealed that lome forest enterprises used to have their own draught animala; but beoause of the drivers' oarelesB handling or their eaBerneBa to produce, which reBulted in BxhauBtion and weakneBs of the overworked oxen, the companiea decided to employ oontraot worker. with their own animals. However, eome amall oompaniel were etill uBing their own draught oxen.

Pile of pulpwood bolts arranged in staok metree (Nacimiento, Chile'

11 1 atack metre. the roundwood of radiata pine, u.ual~ intendad for the pulp and paper induatry, whioh when piled is 1 • high b,y 1 m wide and 2.44 m long.

- 13 -

The hourly oost of an ox-driver, oaloulated nominally on the information supplied by a Chilean forest enterprise, is shown in Appendix 3.

1.2.5.2 Variables applied to determine the oost of skidding with agrioultural tractors

The methodology developed to determine oosts was based mainly on the guidelines set out in researoh works by A~a (1915), Overgaard (1915) and Frisk (1912) and the pro­oedures proposed by the Caterpillar Tractor Co. (1915).

Both fixed and yariable oosts of an agrioultural tractor of &n1 model varied greatly. This variability depended on several factors, of which the main ones were the olass of work done; local prices for tractors, petrol and lubrioants; and interest rates. An exact oaloulation of hourly cost must therefore take into account the looal experience of each region or oountry.

Hourly oost was determined by adding the oost per hour of the tractor to the oost of the labour of the driver and the ohokerman. The general formula used was B8

follows:

Ch ~ Cht + Chl

where: Ch. total hourly cost

Cht. hourly oost of ownership and operation of tractor

Chl. hourly oost of labour.

Basic information and values of hourly cost are shown in Appendix 6.

a) Fixed oosts

Interest

This is a 'loss' value and represents the income which would havs acorued if the price of the tractor had bsen deposited in a savings bank at fixed interest. The rate used in the present study was 12 percent per annum.

I ! fVi + Vf~ -B-• U 2 100

I • (Vi + Vf 12 U 2 100

I • (Vi + Vf) 12 U200

where: I. cost of interest

Vi. initial value of the tractor (inoluding the logging winch)

Vf. resale or final value of the tractor (including the logging winoh)

U • annual use of the tractor, in hours

R • rate of intersst (12 percent).

Depreciation

Depreoiation in forestr,y acoounting term. is a meana of reoovering the original investment in a machine and acoessories.

The method of depreoiation suggested in this study is based exclusively on hours of use per annum.

Ca • Vi - (Vf + Vt) ~

where:

- 14 -

Ca _ hourly oOlt of depreoiation

Vi _ puroh .. e value of the tractor (including the Ikidding winoh)

Vf _ rea ale value of the tractor (inoluding the winoh)

Vt replacement value of the tiree

N _ Uleful life of the tractor, in year.

U annual Ule of the tractor, in houri.

AI .~ be ob.erved from the preoeding formula, tire. were excluded, .inoe they were oonsidered as high-oolt, quiokly worn out article. (Caterpillar, 1975) and their replacement value wae oarried over from the initial prioe of the tractor.

Lioenoe

This oovered the expenses inourred in acquiring the lioenoe without which the tractor oould not be driven. In Chile the lioenoe is renewed every year.

where:

L CL - U CL - hourly coet of the licenoe

L annual ooet of the lioenoe

U • annual UBe of the tractor, in hours.

b) Variable ooets

Repairs

This refer. to maintenanoe expensee, including the value of epare parts and labour but excluding the wAles of the operator~ Some oompanies or individuale kept reocrda of thele ooata, whioh provided the beat information for determining the oost per hour of repaira. Where there were no reoorda it was UBual to oaloulate repair costs as a peroentAle of the initial oost of the machine.

In the study 90 peroent wae used. This wae the factor proposed by Caterpillar (1975) to estimate this type of OOlt for wheeled forest tractors working in areas where they were eubjeot to strong impaots from atonee and rooks, which were olassified (qy Caterpillar 1975) as Zone C. Theae characteriatica were similar to conditions of forest­ry work.

Cr • (Vi - Vt)r (Vi - Vt) 0.90 RU - tru

where: Cr - COlt of repair. per hour

Vi purohase value of the tractor (inoluding the s~idding winoh)

Vt replacement value of the tires

N ueUul Ufe of the tractor, 1n ,&ara

U annual UBe of the tractor, in hours

r repaire factor - ~ - 0.90.

!!!.!! The oc.t of tirea was oonsidered aeparately, .inoe it was very high. An esti­

mate of the life of the tirea was made in the light of experienoe.

Vi Vt - N -3000

where: Ct _ oo.t of tirea per hour

Vt replacement value of tire.

N - Uleful life of tire., in houre.

- 15 -

The average life of tirea was aatimated at 3 000 houra (Caterpillar, 1915).

~

Fuel oonaumption oan be acourately determined at the worksite. If there il &n7 difficulty the tractor manual m~ be oheoked.

Fuel oosta varied acoordinB to the apeoifioationa of the tractor, the w~ the operator drove, the weight of the load, the topography and the lenBth of time the tractor vaa in use, amonB other thinBs. For thia reason, oo.u,tbn reeiatered in the tielA oould often be different from that ahown in the manual.

In preparinB the present atudy, fuel oonsumption was determined on the worksite, and the ooata were oaloulated accordinB to the followinB formula:

where:

Of' • Ch It Vf

Cf • cost of fuel per hour

Ch • fuel oonsumption per hour

Vf • value of fuel per litre.

Lubrioants, filtera and grease

Thia oovers the oosts of ohanginB the oil in the enBine, tranamiasion and gear­box and other lubrication jobs.

Aooessory equipment

Thia oovera the cost of buyinB the steel hooks and oable needed to haul the timber.

Maintenanoe

ThiB refers to ths time and oost involved in the specifio work of maintaininB the tractor, suoh as oheoking the water in the radiator, watohinB the oil level. oheokinB the brakes and fuellinB the tractor. For the purpoaes of oaloulation it was estimated that the traotor driver spent 15 minutea every ~ on thia kind of work.

Labour oost

As well as the wagea paid to the tractor driver and the ohokerman, these oosta included bonus p~ments made for the volume moved.

1 .3 GENERAL CONDITIONS OF THE STUDY

Information oolleoted on draught animals involved different teams of oxen in whioh individual animala weighed between 500 and 100 q. It was asaumed that they all had the aame oapacity for work. SkiddinB wa. oarried out with oxen and ox-drivera with experience and atable production levela. Obaervations were made in the yarde of Chilean foreatry enterpriael.

The time atudy on skiddinB with an agrioultural tractor wal made in one place on~, and therefore reflected on~ the oonditionl prevailing in that partioular foreltry enterpriae.

The tractor did not have front ballast to balanoe thp. weight of the winch and the load, a oondition in whioh power and output are not of the belt. On~ the oable of the winch was used in loading, without aliDSI whioh ahorten loadinB time and thus reduce ooatl.

Time Itudiea of akidding with oxen and with an a,ricultural tractor took into acoount on~ the actual work timea and oOlllputable aupplementary timel, diaregardinB time Ipent on other activitiea lUoh aa Itacking and loadinB truoa.

- 17 -

PART II SICIDDlRO WI'lE 0XEIl

Skidding with oxen in plantation for •• t. (t.aatarria, Chile)

- 18 -

2.1 DRAUGHT ANIMALS THROUGHOUT THE WORLD

In mBnJ regionJ of the world animal. are the prinoipal .ouroe of energy for a&rioultural and fore. try work and for traneportation. Various .peoie. are used, the mo.t important being bovine. (oattle, buffaloe. and yake) donk~., horae., elephant., llamu and mule.. Aooording to Ramuwamy (quoted by Stark~, 1982) there are approxi­mately 300 million draught animal. in the world, of which 225 million are bovine., used e.peoially in developing oount~e ••

Re.earch by Smith (1981) and Hopfen (1970) .howed the approximate geographical di.tribution of animal. working on the land. For example, oxen u a .ouroe of energy are important in Latin Amerioa (partioularly Chile, Brazil and Mexico), in Afrioa, especially Ethiopia and .outh of the Sahara, in the United Arab Republio and in .outhern and eastern A.ia. Buffaloes are partioularly popular in .outheaet Alia and E&Ypt.

Donltey. and !lUle. are used for tranaportation, oarrying loade and field work in South Amerioa, Egypt, the Iberian Penin.ula and .everal oountries in the Near East. Camel. are used for traneport in de.ert. and arid zone. from West Africa to China. The elephant i. used for work and transport in India, Sri Lanka and .everal oountrie. in eoutheast Alia.

Horses are important draught animals in Chile, Brazil and Mexioo, but in general their use i. dimini.hing throughout the world. Llamas are used as beuts of burden in the South Amerioan And... The la1t i. used for the .ame purpose on the plateaux and moun­tain ranges in the north of Central A.ia.

From the above it m~ be .een that there is a considerable potential in draught animals, of whioh ver" little i. known oompared with animals for meat or milk production. In view of their import anoe, Smith (1981) .ugle.ts the establi.hment of an international re .. aroh in.ti tute to .tud1 more way. of using them.

Skidding with a hor.e and with oxen in a radiata pine fore.t (San IgnaciO de Palomare., Chile)

- 19 -

2.2 SKIDDING WITH DRAUGHT ANIMALS

In Chile mainly non-GIeohaniled lkidding methods are traditionally used, parti­oularly oxen oombined with lome mechanised equipment. In the ItU~ only Ikiddina with oxen was covered, with lome relearoh on the ule of horees, the relultl of whioh II., be found in Appendix 4. 2.2.1 Skidding with oxen

Former studies inoludl the following: a) Eilenhauer (1969) oarried out research on Ikidding with oxen in a forest of radi­ata pine with the following oharacteristics: the treel were 24 yearl old with an average diameter at breast height (d.b.h.) of 32 om and average height of 24 m. Danaity was 600 trels/ha. The logs tranaported were crossout in the Itand, to lengths of between 3 and 1 m.

In the above oonditions, skidding on a slope of 11 peroent and over a distance of 12; m, the time per m3 was 36.86 minutes and the output was 1.48 m3/h.

b) On the basis of information oolleoted i. Datural foreat hI a forestry enterprise, Hernandez (1969) obtained an output of 11.31 m3 a ~ skidding logs with oxen from the felling site to a feeder road, over distances of 50 to 200 m.

He also found the output W88 6.55 .. 3 per working day 'tranlporting logs in carta drawn by oxen from feeder roads to landings, over distances of 1 000 to 1 500 m.

c) Jelvez (1911) studied the output of oxen in a forest of radiata pine subjected to thres types of thinning: selective, systematic and mixed. Skidding was done in a stand 12 years old, with 1 110 trees/ha and average diameter of 19 cm.

In the selectlve thinning, using ox-drawn carts over an average distance of 25 ~ the tlme taken to transport 1 m3 of timber was 33.19 minutes, and the output 0.89 m3/h. The logs were 2.44 m long.

In systematio thinning, skidding included the hauling of long logs (where the whole

31ength or the trunk oould be used) over an average distance of 31.5 m. The time

per m was 11.62 minutes, and the output 1.10 m3/h.

For mixed thinning, a oombination of the two syatems where the average distanoe was atill 31.50 m, the time and output were the same as in syatematic thinning.

There are other atudies on akidding with oxen and horses, but their results are not given here because th~ include stacking time, whioh is not taken into account in this stud,y.

2.3 GENERAL INFORMATION ON OXEN AS DRAUGHT ANIMALS

2.3.1 Advantages and usea

Since ancient tim", the ox has been used as a draught animal and although there are no precise reoorda, it appears that cattle were uaed as a source of energy before th~ were used for milk or meat produotion.

The ox is veraatile; it oan be used in agrioultural and foreatr,y activities and as a meana of tranlport. Oxen oan be bred directly qy peas ant I who therefore do not usually need to buy them and oan alao produoe the feed thay require. The ox is alow but steady; it is har~, strong and easy to drive, and at the end of its active life, after having been fattened, it provides a good yield in beef, ao the inveatment in it oan be recovered.

In agrioulture oxen as animal power are used mainly for ploUShing and oultivat­ing the land. As tranaport animals they are used mainly with oarts and wagona, or for travelling on narrow paths and roads in bad oondition.

- 20 -

Using oxen to transport forest produots on rails (Forest and Timber Complex of Panguipuili, Neltume, Chile)

U.ing oxen for lateral loading of log. in plantation foreet. (L&atarria, Chile)

- 21 -

OXen used to be indi.penaable in fore.t operations alao.t everywhere in the world (FAO, 1983); however, tod~ the, have been widely replaced qy different type. of machinery. For .ome people, oxen are a .i,n of teohnioal backwar4n .. I, but it .hould be pointed out that m&nl fore.t enterprile. oontinue to reach good level. of produotion with them. Whereat the art and teohnique of workin, with them have been lo.t in many areas, oxen are still important in forestry activities - particularly skiddin, - in both plantation and natural forest ••

In Chile in 1982 approximately 90 peroent of .awmilll (lome 696),11 three oom­panie. produoin, pulp and paper, and liven board factoriel used oxen in axtractin, timber, frequently oombinin, the UBe of drausht animals with forelt tractors (CONAr, INFOR, 1983). It il eltimated that there are leveral thousand teams of oxen used in skidding, in both plantation and natural forests. They are also to be found workin, in small sawmills to transport logs from the storage yard to the main law, and on some aites, espeoially in natural forests, loadin, logs on to trucke, doing the work usually done elsewhere by mobile oranes.

2.).2 Morpholosioal oharacteriltios

Oxen employed in skiddin, vary from one breed to another, but there are oharac­teriltioB that are oommon to many.

Agenjo (1945) observed oertain features which should atill be prelent in akid­din, oxen. The main ones (aee Fig. 3) are: aolid head; back of the neok must be in good oondition (beoause the yoke reats on it); horne well Bet in the head and firm, well­developed and fairly straight, facilitating the fixin, of the straps uled to settle the yoke; neok ehort, thick and powerful since it takes the weight of the timber; ohest wide and deep; withers well defined; hindquarters musoular or with prominent bones.

~fL-'-jt--1I

;~--II

+--+~--I' 14

\.l1li1--11

+~-IT

';---te "",,-,~--I.

Fig. 3 PRINCIPAL MORPHOLOGICAL PARTS OF A DRAUGHT OX

1. Head 2. HOml 3. Nape of neck 4. Parotid 5. Neck 6. Withera 1. Chine 8. Loin 9. Hindquartera 10. Croup 11. Thigh 12. Rump 13. Knee 14. Tail 15. Leg 16. Hook 11. Shank 18. Fetlook 19. Pattern and ooronet 20 and 21. Hooves 22. Flank 23. Stom­ach 24. Ribl 25. Heart 26 and 21. Fetlook. 28 and 29. Roov.. 30. Coronet 31. Pat­tern 32. Fetlook joint 33. Shank 34. Knee 35. Upper forelee 36. Dewlap 31. ~~oulder and fonlee 38. Dewlap

11 In 1982 there were a total of 1 498 .awmill., of which only 913 were functionin, (CONAr, INFOR, 1983).

- 22 -

The torequarters and hindwuartera must be oorreotl1 balanoed and well tormed in their various partal ahouldera larse and powertul; torel.,a lons; oroup lons with reo­tilinear rump; 118' lons and hook jointa wide. The l.,a (oonaiatins of the ahanke, tet­lock jcinta, paeternl, coronet a and hocves) are ver" important in akiddins animala; they .hould be ahcrt and atrons, and it ia alao d .. irable that the hoovea be hard and re'istan~

The averlle weisht of an ox ia 600 kg.

Size. var" with breeds and individuals. De la Maza (1969) oonsiders average measuremente to be 2.70 to 3 m in length, 1.50 to 1.80 m in heisht and 0.80 to 1.10 m in depth (width).

Oaatration, training and handling

In forestry work, cxen are used in pairs or teams and their suocess in skidding depends on taming and training and the harness used.

The oalve. selected should be males, beoause the wcrk i. hard. Tha,y should be acoustomed from an early age to .. eins pecple on the farm where they are born, and as young animal. tha,y should be in frequent contact with human beings sc that they do not get frightened and are accUitomed to hearing the vcice of command. It is desirable to keep them in place. where they have freedcm to move around and exercise their musoles and jointa, which help develcpment. It is also reoommended that tha,y be aeparated from othera of the aame ,peoiea.

Oxen are oastrated before trainins. Ensminser (1970) e&3s that castration should take place between the fourth and twelfth monthe, and Agenjo (1945) believes that it should be done at eight to ten months. Castration befcre the animal is one year old oan inhibit musoular development of the fore- and hindquarters, particularly the shoulder, neck and thighs (Goe, 1983). FAO, (quoted qy Goe, 1983) recommends castrating cattle when tha,y are a year and a half to two years old. Although there are different criteria, the age of castration varies aocordins to species, oountry and region.

Castration oan be done at any time of the year. However, it is better to do it in periods of moderate temperature, partioularly in the spring and autumn or a little before the rai~ season, to reduce the possibility of infection by inseot, and because excessive heat or oold produoea funotional disorders. The suppression of the sexual or­sans ia intended to reduoe aggressive behaviour, making the animals more dooile (Navajas, 1955).

The age when training starts varies in different oountries. Hopfen (1970) oon­sidera that it m&3 be when the animal a are between one and a half and two years old; FAO (1983) givee the appropriate age as atter three yeare. A eurva,y made by the author of this work in different foreat estates in Ohile found that trainins atarts there at two and a half years and last&for six montha.

The trainins b.,ins by setting the animals acoustomed to a double head yoke, that is to a~, being in a team, and training at thia point is practioally limited to toleration of the yoke. Later tha,y draw a oart, bearing light loads that are gradually increaaed in order to accUltcm them to the neoesaary weights. In these two stages, when experienced oxen are available a young ox is paired with an animal already trained ao that the bl8inner will be dominated b.1 the etrength of the adult.

In the last etage the trained ox is taken to the forest and yoked with another of the eame age. The animal is oonsidered to be oompletely trained when it has reached maturity (at apprcximately five yeare) and ie oapable of hauling full loads (FAO, 1983).

- 23 -

Using young oxen to draw cartl in a lawmill (Lol Sauoes, Chile'

To handle oxen well the driver must have a good knowledge of the animall' oharac­ter and a fair amount of practioe. Commands are given in the local language, to avoid oonfuaion if there is a change of ownerlhip or district, although it ia alw~s best if one man drivel the lame team of oxen for aeveral year I (in practioe lometimes difficult to achieve). The words of command should be Ihort and the driver Ihould be able to make the oxen understand when to go backward or forward and when to turn or stop. An experi­enoed driver does not need to goad or ill-treat the oxen because the animals will ob~ the word of command.

An inexperienced driver sometimes keeps urging the animall on, and obtains an excellent daily output in skidding; however, in time the oxen become exhausted, output falll and the useful life of the animals il shortened.

In lome places it is ouatomary to give the ox a name, and th~ will obey when called by name. The animals are responsive to patting and kindly treatment; they easily beoome affeotionate, just as they are resentful when ill-treated. The oloser the link between the man and the animal, the more efficient the latter beoomes.

Aooording to FAO (1983), oxen can work up to the age of ten or 12 years, an ob­lervation that acoords with the survey made by the author in Chile; and their useful life il between lix and leven years.

Load capacity

The load oapacity of oxen in skidding is in relation to the weight of the ani­mals, the topographioal oonditions, the olass of forest, the denlity of the timber and the size of the logs.

- 24 -

Skidding with oxen in a radiata pine forest (Naci~iento, Chile)

Maximum volumes and weights are obtained when skidding downhill. Aocording to information gathered by the author maximum skidding loads were in natural forests, where the oxen managed to haul loads squivalent to more than twioe the weight of an ox of 600 kg.

2.3.5 Pull strength, tractive effort and power

The pull Itrength exerted qy oxen to transport logs depends on various factore, of whioh the prinoipal ones are: the weight of the ox iteelf or of the team, weight of the load, angle of draught, dietanoe oovered, ooefficient of friotion between the logs and the loil, elope of the ground, method of transporting the load, climatic conditiona, and intensity of the work.

The tractive effort variel between 10 and 14 peroent of body weight, with apeeds between 2.5 and 4.0 km/hour (Ooe, 1983). The power generated b,y the oxen is related to the rate of work, that ia to s~, the faster the rate, the greater the power. For ex­ample, a team of oxen weighi~ approximately 1 200 kg dragging a load with a tractive effort of 120 kilopounds (kp) . at a .peed of 0.10 metres per lecond (mi.) will produoe a working power whioh, upre"III1Q in the form of energy as suggested qy Sears and Zemansq (1963), i. 0.82 kilowatt. per lecond. If this apeed drope to 0.60 mia, the power il 0.;6 kW per .. cond.

Table 2 .howl .ome values of draught capacity (or tractive effort) and working power of oxen, which have been taken from Goe and XODowell (quoted by Goe, 1983).

- 25 -

Table 2

ESTIIATED DRAUGHT CAPACITY OF OXD WITH DRAWN DlPLDIIffTS AT LOW AND AVERAGE WORKING SPDm

Low Speed Average • peed

Type of ox Mature 9,..4 Trao- Po,,1II' lpeed • Trac- POIlU veight (laD/h) tive (kW) (laD/h) tive (ItW)

(kg) .ffon y effort y (ltp) (.ltp)

1/ 1/

Light 210 2.5 30 0.25 4.0 21 0.23 Medium 450 2.5 61 0.44 4.0 45 0.50 Heav,y 900 2.5 129 0.89 4.0 90 0.99

1/1 kilo pound (kp) · 9.807 NllIton. Newton · kg x!!!... where m • metre

2 .eoond a e •

Joule · kg x!!!... 2 a

1 ICHowatt/. · tv/I • 1 000 Joulea

Y Pover . foroe x apeed •

2.3.6 Feed and energy

2.3.6.1 Feeding principle.

Studiea on the fllding of draU8ht animal. are few and fr8lllentary, and therefore very little ia known about nutrition and p~.iology, e.peoially in developing oountrie. (Smith, 1981).

The quantity of an ox'. feed oonsumption i. related to the animal'. weight and inten.ity of the work. Skidding animals, beoause of their enormous .i.e, have di,e.tive organa oapable of oonauming and di,88ting large quantiti88 of feed; however, when the work i. intensive, overfeeding impede. movement and effort, prolonging rumination, with losa of work output.

'eeds and rationa vary with different oountrie., rasiona, d!.triots and oustoms, but in general they oonai.t of lar,e quantities of ha,y and .traw, bran and plenty of "ater. When oxen are doing heav,y work hauling lop, it i. usual to reed th8111 three tillea a~: in the mornine, at l ... t an hour and a half before .tarting work; at middaJ, "hen th.r are-Allowed to re.t at the .ame time, and in the evening, when work i. fini.hed. When the anillal. are re.ting over the wealc-ea4, feed oontinue. without ohance, but "hen re.t perioda are longer the ration ~ be reduoed by half and they are left to gra.e frilly.

Aooording to Goe (1983) the feed requir .. ent. of lIature working oxen are for organio maintenanoe and work, while illlll&ture ani.al. have add! tional neede.

Aotive oxen need a daily ration oontaining 2.5 to 3.0 q of dry lIattar per 100 q of live weight of the animal (Inaminger, 1970) and oould be hieher for .kidding ozen.

- 26 -

Tradi~ionally, ~h. ba.io f.ed of oxen haa b •• n gr ... , oonsumed direo~ly or in ~h. form of h., or eilag., for a Ions ~im. it haa b •• n the mo.t .ffici.nt and oh.ap •• t fe.d. A sup­plem.nt of barley or bran oan al.o form part of the ration. Xatur. oattl. oonsume 45 litr •• of water a d~. Wat.r i. indi.p.nsabl. for digeation and ... imilation of fe.d, the .limination of wa •• product. and the regulation of body temp.rature. The animal. should have aa muoh wat.r aa they want.

In practio., driver. oan measure the effioi.noy of the f •• d and the ration ac­oordins to how th.y aff.ot the animal.; the lose, gain or stability in weight of the oxen is ob.erved, .inee the.e are the visible r •• ult. of the quantities giv.n.

2.3.6.2 Bnergy r.quirem.nt.

Iven when an ox i. r.stins or not makins aqy phy.ioal effort, it n.eds f.ed to r.plac. the en.rgy .pent in it. organic maint.nanoe (for funotioning of the organs, main­taining body temperature, and r.placins prot.in. and vitamin. eliminated in exoretion and water .liminated in liquid and ga.eou. form).

Aft.r feedins, the animal lo.e. ch.mioal energy, which oome. out of the organism in dung, urin., gaa •• and al.o in the form of heat by dir.ot radiation, oonduction, oon­v.ction and bf evaporation through the lung. alld th •• kin (MoDonald, 1979). Th. remaining .n.rgy from th. f.ed i. metabolio and g.n.rat •• two form. of .n.rgy: thermal and n.t.

Th.rmal .n.rgy i. g.nerat.d by the proo •• s of digesting f •• d; the net energy of the f •• d is that which the animal uses for th. maint.nance of it. organism, and the re.t oonstitut •• r ••• rv •• to und.rtake phy.ioal work and for fattening. The following dia­gram, tak.n from XoDonald (1979) .how. the distribution of animal energy.

Gro ••• nergy (z heat of combustion)

Gross energy (- heat of combustion)

r-------- ~I --------~ Energy from faeces Digestible energy-energy from the reed digested

r--------r------~I -------, Urine Methane

energy energy Hetabolic

energy

r------~ Thermal increase

Net energy

I I I I I I I I I

I Used for bodily mainte-

l ___ ,-::J"

I

Total calori. production of the animal (maint.nance of the organi.m)

Used for production (retention of energy or balance)

It baa b.en mention.d that animal., ev.n if they are not working, n •• d a minimum maintenance ration. If they are deprived of fe.d, or when the quantity received i. not enoUBh, anergy for aaintenance i. obtain.d from re •• rv •• acoumulat.d in the fat throUBh the procell known .. oatabolilm. Thi. leada to a 101. of w.ight (MoDonald, 1979). Work­ing oxen need te.d over and above the l.v.l ot maintenance. On. w~ of oalculating the addi~ional needs il bf oonsiderins the houri of work ever,y ~, the type of work done, and the pull Itr.ngth r.quir.d, .xpr •••• d in terms of .n.rgy.

- 27 -

, Tabl~ 3, taken from Goe and KQDow.ll (quoted b.1 Goe, 1983) Bhow. the total di-gestlbl. nutrlents (TDN) for ox.n of different weights, working perioda of 4, 6 and 8 hours a, d~, with efforts of 10, 12 and 14 peroent oompared with their body w.ight. On the baa~s of the above peroentages the work was olassified as light average and h.a ..... respeotlvely. ,.",

Table 3

ESTIMATI!lD TDN NEEm OF OXEN OF VARIOUS SIZES WORKING AT DIFFERENT RATBS oP 4-, 6- and 6-HOUR PBRIOm

Weight (leg)

250 250 250 300

300

300

350 350 350 400

400

400

450 450

450 500 500 500

550 550 550 600 600 600

Souroe: II Y

Tractive Traotive Spe.d Power TDf needa y effort effort II (m/h) (leW) (kg)

(kp) (~) 4 h 6 h 8 h

25 10 4.0 0.28 3.3 3.8 4.3 30 12 3.5 0.29 3,5 4.0 4.6·

35 14 3.2 0,31 3.6 4.3 4.9 30 10 4.0 0.33 3.1 4.3 4.9

36 12 3.5 0.35 3.9 4.6 5.2

42 14 3,2 0.31 4.1 4.8 5.;

35 10 4.0 0·39 4·2 4.8 5.4

42 12 3.5 0.40 4.4 5.1 5.8

49 14 3,2 0.43 4.; 5.4 6.2

40 10 4.0 0.44 4.1 0;.4 6.2

48 12 3.5 0.46 4.9 5.8 6.6

56 14 3.2 0.49 5.2 6.1 1.0

45 10 4.:> 0.50 5.2 5.9 6.1

54 12 3.5 0.52 5.4 6,3 1.2

63 14 3.2 0.56 5.6 6.1 1.1

50 10 4.0 0.5; 5.4 6.3 1,1

60 12 3.5 0.58 5.1 6.1 1,6

10 14 3,2 0.62 5.9 1.1) 8,1

55 10 4.0 0.60 5.1 6.6 1.5

66 12 3.5 0.64 6.0 1.0 8.0

11 14 3.2 0.68 6.3 1.4 8.5

60 10 4.0 0.66 6.1 1.0 1.9

12 12 3.0; 0.69 ~.4 1-'; 8.5

84 14 3.2 0.14 6.1 1.9 9.1

Goe and McDowell (quoted by Goe, 1983) Peroentage of body weight developed as tractive effort Inoludes daily needs for maintenanoe. TDN: digestible protein + free extract of N + digestible fibre + 2.25 (extract of digestible .ther) (MorriBon, 1941). 1 leg of TDN • 4.409 Moal of digeetible energy and 3.615 Meal of metabolizable energy (ME)(Crampton and Harris, 1969).

The most oommon ailments of bovines are diseases of the mouth, the lungs, the stomach, the skin and the eyes, and infections of the hooves (Book, 1911). In this study 80me diseaseB in the last three groups will be desoribed, beealUle th .. e are the ones that the driver oan diBtinsuish most easily and because they are more likely to OQour with oxen used in Bkidding. Other diBeasBl that require immediate assistanoe from a veteri­nary surgeon are not disoussed here.

- 28 -

H.ur1ene and di ......

'l'he h.alth ot oxen d.pende llU'g.ly on their .nvironment. Ib'gi.n. ie not upen­live; it helpe to avoid di ...... , and i. more Uleful and 100nomio than ourill8 them.

When there are .table. or pen. for .kiddill8 animal. that are usually there for .hort periode only, th~ .hould b. ol.an.d ev.Z'7 d-.v if po •• ibl.. Thi. ol.anill8 cone i.,. of r .. ovill8 th. dUJIC .0 that oxen have a d%'7 bed. 'l'h. ox.n th.lD8elv ••• hould b. ol.an.d with a brush and wat.r ono. a week, on re.t ~., to k •• p th •• kin h.althy and fr •• of par .. it •• and outan.ous di ...... .

Driver •• hould watoh the animal. oontinually to detect any .ign of abnormality in th.ir behaviour that oould b. th. fir.t .ymptOlD of a di .. as.. Thee. ligna are usually oonn.ot.d with eveZ'7da3 proo ••••• , .uch .. : phy.ioal movem.ntl, temp.ratur., pul •• , re­.piration, appetit., rumination, defecation, emi •• ion of urine and work output. An ox in repo •• reepir •• 10 to 30 tim •• a minut.. It h .. from 40 to 60 pul.ation. a minute and a normal temp.ratur. of 38.2 to 39.5 C. With work, 8ltOitem.nt and .xtr.m •• of heat or oold, th •• e rat •• ri •• (Wooldridge, 1962).

2.3.7.1 Skin di ......

a) ~

Ox.n in a field or in the forest are liable to pick up ticks which etiok in the animala' skin.

Tioks .ubtract blood, implant a toxio secretion and transmit intc the blood parasites that d.stroy the r.d cells through int.nsive reproduction. Infestation can producs inflammatione in the skin, f.v.rs, spasmodic contractions, phenomena of paral­y.is, restlessnsss, loss of w.ight, damage to the skin due to bites, and loes of blood.

Drummond (1976) reoommends that tioks .hould be oontrolled by applyill8 to the host animal and to the .tabl •• acarioide. baa.d on ar.enic (AS203) and ohlorinated hydro­oarbone, •• peoially ben •• n. h.xachlorid. (BHC), whioh are .conomioal and effective. In applyill8 acarioid.s, the instruotions of a vet.rinary .urg.on should be oarefully fol­low.d, .ino. th.s. substanc.s oan be poisonous for liv.stook and human beings.

b) P.dioulo.i.

'l'hi. is the reeult of lice in the animals, and occur. mainly in those that are badly ted and hous.d in unhygi.nic .table ••

'l'he lioe .uok the animals' blood two or thr.e times a da3. In pisroing the skin th~ produo. p.rforatione and oons.quently pain. Larg. number. of them lead to urticaria and ths formation of soab.i the mov.ment and the bite. oaus. itching, whioh leads the animals to bite them.elv.s and rub againet their .tall.. Lice ars oontroll.d with con­tact ineeotioid.s, rep.ating th. dose ev.ry .ight or ten days.

0) Ringworm

'l'his i. a di •• as. produo.d b,y fUlJ8i (.sp.oially Triohophytun v.rrooo.un) whioh are pr.sent in damp wood, fodd.r, IDoul4y straw and dUlJ8. They are ver,y r.sistant in this environm.nt but •• nsitive to sunlight. 'l'h. fUIJ8UI stioka to the bas. of hair., we&lt.nill8 and finally loo .. ning them, oausing a smarting .. n.ation and obliging the ani­mal. to rub th.ms.lv •• against aqythill8 available, thUi produoill8 round bar. patoh.s on the .kin.

Ringworm i. oontacioUi and oan b. tralllmiUed to humane. It oan b. r.oognized b,y ohiU'aoteriltio abr .. ions, bar. round lU'eaa oov.r.d with thio~, oallous flakes. 'l'hil di ..... i. treat.d with anti~ootios suoh .. ohloro~o.tin, tinotur. of iodin., formal­d~de, oreClote or .alioy1io aoid ointmentl.

When, d .. pite good feeding, ilolat.d lelione appear y.ar aft.r y.ar, th. mo.t probable reaaOD 18 that the .tabl .. lU'e inflOted, in whioh 0 ... they should be thoroughly ol.an.d b,y .0rubbill8 with hot water and dilinfectant.

- 29 -

Th ... are oaused by a virus infection and acoordinc to Boolt (1971) the IIO.t eerious invaeiona are in animal. with a low .tate of health. When wart. are pres.nt all ov.r the bod¥ the b •• t thil1l i. to l.av. the ani.ab in peac., It.epil1l them ol.an and w.ll f.d. A .mall wart IU,Y b. raJIoved n.ry da,y with di.inf.oted hande, applyil1l a iiolu­tion of .ulphanil&lllid. illlDediately afterwarde.

Th. applioation of &n¥ non-irritant antis.ptio i •• ff.otive in oontrollil1l wart.. The primitive m.thod of tyinc li,atur.s around tbe,baee .hould not b. us.d, b.oauB. the,y ma,y produce ulo.rationa, facili tat il1l invaeion by ,.rlDll that oan oaus. teta­nue and oth.r di.turbanc.s.

2.3.1.2 Hoof problBIIB

a) AbBo •••• s

The.e are inf.ctions in the low.r part of the extr.mity produo.d perhaps by a nail piolt.d up from the ,round or a out in the .ole with some .harp obj.ct. They beoom. appar.nt fairly quickly beoaus. the animal go.s l&llle.

Metioulous exploration by a v.terinary surgeon is needed. H. mak.s a small cut to extract the forei,n bod¥.

b) Hoof rot

Thia ia oaused by a germ (oalled Fusiformie neorophorus) that oan live for years in the olefta and fiasurea of the hoovee, and r.produo.e ~en it finds the appropriate oonditiona, the id.al place beil1l a leaion, out or crack in the ekin between the naile around the root of the heel. Infection ie more likely when the animal repeatedly has its feet in mud, dirty wat.r, dUI1l or urine.

Reproduction and attack by the ,erme oause painful swellil1l followed by necro.is of the affeoted part, with a putrid smell. If the infection is not treated in time, eecondary septio complications ariae whioh in turn oan affeot a joint.

Aooordil1l to Book (1971), thie dieeaee ma,y be avoided by waehinc the animals' feet once a week with a 3 peroent copper sulphate or a 10 percent fcrmalin solution. It ie deeirabl. for the animale to tread on a thiok la,yer of earth or a heap of ordin&r,J lime every da,y, beoause lime keepe the ekin on top of the heel hard and dry.

c) Stones in the hooves

When the oxen have to croes gravel paths, .ton .. oan ,et ri,ht into the sensi­tive underlyil1l tiseuee of the sole of the hoof, oausinc lamene.e.

If the part affected ie struok with a emall hammer or the handle of a spoon, the animal reacts to the pain by ltiokil1B Violently. The .uspect area oan then be explored until the forei,n bod¥ ie found. Onoe it ia taken out the oavity ie filled with anti­biotice, lteepil1l the foot oovered for four or five da,ya.

2.3.7.3 Ooular di.ord.rs

a) Foreign bodies in the eye

To .liminate from the e,ye ohips of bark, wood or twi,e, take a tube of eye oint­ment, equ.eze it a little until a .mall quantity appeare on the nozzle, elowly approach the eye and pr ... the ointment againat the forei,n bod¥. The animal involuntarily throwe ita head back and the foreign bod¥ remains .tllCk in the ointment. Afterwards a small quantity of ointm.nt oan be insert.d in the e,y. to avoid infection. If suco •• s is not achiev.d after •• veral attempt., a veterinarian .hould be oall.d.

b) Infectious Iteratiti. (pink ele)

Thi. talte. the form of a flow of •• roue liquid or a olosed e,ye. Thi. infection oan aff.ot both e,ye., and beoause it develope very rapldly a veterinarian .hould be oall.d to treat it quiokly.

It i. started by a ,erm (oalled Moraxella !2!!!) whioh becom •• active wh.n there ia a l .. iol1 in the .urface of the eyel damage oaused by forei,n matter, partiol •• of dust n~ i~pit..t.;n" hv fli •••

- 30 -

2.4 SKIDDING EQUIPMENT AND HARNESS

SkiddiDi ham... for ox.n .hould b •• 0 d •• ign.d as to allow the animal. to work oomfortabll and .ffioient~. Hopt.n (1970) r.oomm.nda lev.ral oonditione to b. born. in mind:

a) It must allow .ffioi.nt and spe.dy work with the minimum of fatigu.;

b) It must not b. injurious to man or animali

0) It mu.t b. of limpl. d.liln and .asi~ available mat.riall 10 that it oan b. mad. looal~i

d) It must be light in w.ight for .asy tranaportation;

.) It Ihould b. ready for imm.diat. use to lav. time.

2.4.1 Desoription

(Not.: Only the .quipment oblerved in ule during the preparation of this ItUdy il deloribed below.)

2.4.1.1 Double head yoke

Thil mOlt anoient type of harnell (Hopfen, 1970) conailta of a pieoe of wood fix.d on the head with yoking It raps or belts (se. Fig. 4).

The yoke Ihould be mad. of light but tough wood, 10 that it oan Bupport weights of approximat.~ 500 kg when the load il luspended. The length variel between 1.8 and 2.6 m and the weight 12 to 15 kg.

The under side of the yoke, whioh liel acroll the OX'I neck should be arohed to fit oomfortab~ without rubbing. In Chile it il ulual to inolude an extenlion at the back, oalled ~ the ox-driverl a neck flap, to Ipread the weight of the load and allo to avoid injuries.

neck flap

---+ 11 +-- 35 --+--- 50 ---+~ 14 +1--- 50 --+--- 35 ----t 11 +-~.L~ _____________ 206 em.

• ria. 4 Doubl. head yoke for Ikiddiq oxe

A It •• l loop il fixed with l.ather Itraps in the middle of the yoke. Through thil loop pul" the ohain that lusp.nda or dragl the load. As the loops vary in dimen­sione and li •• s, only the mOlt important oharact.ristios are m.ntion.d, name~: it is approxiaat.l;r 1 om thiok and p.ar-ahap.d, with a larl.r upper part and small.r low.r part with an int.rnal distano. Ilightly less than the width of the link. In thi. w~ on~ a Imall turn n •• da to b. liven to the ohain whlll loadilll or unloadilll in ord.r to fix or 1'.1 .... it, and the trac .. m~ b. quiokl;r and l&Ii1,y shorhned or l.ngthen.d.

- 31 -

Oxen with double head yoke (CEFDR, Un1yara14ad Austral de Valdivia, Chile)

The advantages of the double head yoke over other types, listed by FAD (1983), are ae follows:

a) 'Oreater ute i8 made of the animals' weight aa a power source. The yoke ia firmly attached to the animals' horne as againlt free movement on the Iboul­ders. Pull is more even, with no loss of power in taking up the Ilack •••

b) 'As the two oxen are firmly yoked together, they operate better aa a team and ooordinate their movements, together making maximum use of their combined pull­ing power.

c) 'When actually skidding logs the animals adapt themselves to oontrolling the movement of the timber by raising or lowering their heads whioh in turn increases or reduoes the pull required to move the logl.

d) 'Oxen oan be trained to pick up loads at awkward angles qy facing the load, then pulling the load clear by walking backward until the load is free of obstacles ready for normal skidding in a forward direction.'

2.4.1.2 Yoking straps

These are leather straps used to tie the yoke to the OX'I horne. Two are used, each about 2 m long and 1.5 - 2 am wide.

2.4.1.3 Q.~

This securel the load. It il about 5 m long and 6/16 of an inoh thiok. It is passed through the loop in the yoke and depending on the load to be transported baa either hooks or olamps attached.

a) Chain with hooks

This il used whan the ohain can go under ths load, usually when the logl are not very heavy or in oiroumltanoes where faatening posel no problem (see Fig. 5).

It is simple to use. The chain is passed under and around the load, and the hook fastened in.

- 32 -

~aQaLaaa~D e ~ -+ _______ 5 m ------t-

Pig. 5 Cha1n with hoob for ak1dd1ng with oXln

b) Chain with ol_a

The Chilelft os-clrinJ'l oall thea I 'oab'. Ther are Uled partioularly in natural foreata for largHiameter hl&V1 loge, whlre it 1a diffioult to movl thl loge or pall the oha:in UDdemeath. Two olampa on .hort ohaine linked to a rinr are attached to the outBide of the log without loa. of UM 1n 10a4inc and unloadinc (a .. Pig. 6).

Pig. 6 Chain with olampa for tl'Mlportinr larpodillll8hr loge

When the olampa are at the riebt ql .. and are wll aharplned, it 18 not nlOlaa&17 to hammer thlm 1n to iuten thell to the loge. It 11 enoush to put thllll on by hID4. When the osen pull thl lolli, they should I'IIIII1n firmly attached to thl log.

In both thl &bon OUI. 1 t ia UIU&l. to futen only onl eDd of the oh&:l.n to thl lolli, leav1ng thl othlr rolled round thl 1OkI. Thia aave. time and inoreula output, aillOl thl d.r1 VIr nleda to hadle only onl part of the ohain.

- 33 -

A thin wooden stiok about 3 m long helpe the driver to guide and drive the oxen (Fig. 7). Some drivers put a prong on the end of the goad, but if the oxen are well trained and the drivers experienoed, this is not neoessary.

PS &,12 'B 2 <~kt Z 'Ji

--t-------------3m--------------+-

Fig. 7 Goad to guide and drive oxen

Harnessing the oxen

Harnessing the oxen is Simple and is virtually limited to tying and seourely ad­justing the yoke to the horns and neok. However, care should be taken to avoid disoom­fort in the animals or the risk of aooident if the yoke shifts when the load is dragged.

Team of oxen harnessed with ekidding equipment (CEPOR, Universidad Austral de Valdivia, Chile)

One important point in teaming oxen for skidding is to ensure that aa far aa poesible the two animals are well matohed in height and shape. In thie W83 their energy is put to greater use and the work is better balanced.

2.5 SKIDDING TECHNIQUE

The output and oosts of skidding with oxen are favourably or adversely affeoted by the w83 in whioh forest utilization haa been planned.

Felling and its influenoe

Felling in both plantationa and natural forests should be planned to minimize later aotivities, inoluding transport of the load by oxen.

When felling (including thinning) ia aeleotive, the trees must be made to fall in such a w~ that the oxen oan reaoh the load without diffioulty.

- 34 -

In arias of olear-felling too, planning ia very important. If the treea fall in the aame direotion .kidding i. facilitated in varioue v.,.:

a) Th. ekidding area oan be dividld into .trips approximat.~ 10 m vide, vith one team of oxen vorking lach strip. This avoids their oroaaing in front of or meeting another team on the a8lle path. In debranohing the branoh .. oan be oonvenient~ piled at the side of the .trip, and the akidding tracks remain ol.ar.

b) The load ahould be piok.d up eystematioal~, first the loge neareat the landing and last those farthest av.,. In this v., aa the lIhole ar.a, inoluding the pathe, i. gradual~ oleared, the mov .... nt of the ox.n b.oom.a progre.aive~ eui.rl the,y do not have to move in a lig-IBB to avoid obstacles.

0) The ri.k of acoidentl il avoided.

Controlled felling and division of the area into Itripe (Nacimiento, Chile)

Arrang.ment of the load

Even if f.lling ia oontroll.d, it is unlike~ that s.veral large and heavy logs will be ~ing togeth.r. Th8l'e are ther.fore oolleoted, ueing the oxen, and noured (by hand) with the ohain at .ome 30 om from the end of the load to prevent it from breaking loole when the ox.n pull it.

Thin loge are ooll.ot.d by hand. A pi.o. of wood about 15 om acroaa and 1.50 m long il plac.d on the ground, and the loga are Itacked on it vith a olearanoe of 30 om at the endl. Thie facilitates fastening and eubeequent tranaport (see photograph).

IrreaplOtive of the type of load to be traneported the following errora ahould be avoided: drBlling a very .mall load; putting too m&qJ loga in one load; preparing the load in an inoonvenient or avkward place (Soto, 1970).

- 35 -

Thin logs arranged in piles (Nacimiento, Chile)

Paths should be defined before felling starts, and should take the shortest route, with the minimum number of curves, to the landings. Some researoh recommends a maximum length of 50 m on level ground, 15 m uphill and 200 m downhill (FAO, 1983).

When the path has to be retraced several times, it is important that it should bs clear of obstacles such as branohes and sticks. Any stumps should be levelled, and ab­rupt ohanges from a positive to a negative slops or vioe versa should be avoided.

2.6 METHODOLOGY OF STUDIES OF SKIDDING WITH OXEN

These studies on skidding with oxen were not planned in advanoe; information was oolleoted on the spot during normal forest harvesting operations. So that ekidding oould be analyeed in ite traditional form no ohange. in lhe syaiem ware sU8a--'ad io iha 0%­

drivera. In the same work place the parameters deeoribed in thie etudy were recorded 11IIing different teams of oxen, t&lcen at random over eeveral working ~, although it waa ensured that each animal weighed approximately 600 q. This method was chosen to avoid the effeot of a greater or laeser output that might be produoed qy one pair of animale only, due to experience, 8gs, weight, hauling oapacity or the skill of the driver.

Skidding inolllid only minor transport; the loads were hauled over the ground with ohains, with total friction between the lower surface of the load and the eoil.

For each work cyole, the volume of the load was detarmined, the distance was measured and the gradiente were aaoertained in etretches of 5 111, to caloulate the average elope per oyole and group them qy dsgrees of gradient.

The timee and output were recorded on ths basis of the effeotive working hour and inoluded only thou supplementar.y timea related to ekidd.ing aa such, excluding 1088

of tillle for acoidente and raet perioda, e.g. for eating, during the working d~.

It should be mentioned that the equations of time per oyole were obtained qy uling minimum equaree and were the basie for the equatione of time per m3 and the output.

- 36 -

2.6.1 Skidding in radiata pine plantationa

In radiata pine foreltl, dependinc on requirement I and utilis.tion of the forelt re.ouroe, it w .. Ulual to uiract 1&W10l1 and pulpwood. In the fir.t o&le, one to four or more log. oould be .kidded HOh tille. The driver oollected them tOiether, Ulinc the team of oxen, until he had obtained the delired load. In the lecond o .. e, the bolts were pil.d up 10 that loads were alao.t uniform in volume, with 6 to 16 or more boltl per load.

Und.r the above oonditione and on the lame woruite, Ildddilll W&l mixed &I re­gards the type of 101' (.awlog. or pulpwood); that 11 to 'a,y, they oould be tran.ported limultaneoUily but in differ.nt wayl, it being Ulual to load lawlOiI firlt and pulpwood afterwards •

In all the 0 ..... tudied Ikidding path. had not been prepared in advance, and the information Wal oollected in a dry p.riod in two different are .. , .loping and level.

2.6.1.1 Slddding in Iloping ar.as

Th •• tudy waa mad. in a fore.t ent.rpri.e 11 where 20 p.roent of the extraction of raw timber WaB ~ wheeled foreat tractor and 80 p.roent by oxen - perc.ntag.s relatins to roughly 6 000 and 22 000 m3 of raw timber per month. The volume W&l significant, oon­sid.ring that thele extraction ay,teml wer. helpilll to .upply a .awmill that in 1981 had a produotion oapacity of 91 100 II of .awn wood annually (equivalent to 232 000 m3 of round timber), a pulp and paper factory with an annual oapacity of 68 100 tone of newa­print (equivalent to 235 000 1D3 of round timber, and a thermal plant that was oonsuming 12 000 m3 of raw tilDb.r p.r monthl as w.ll &I •• lling aurplue tilDber to other fore.t ent.rpri.e.. The number of ox teame fluotuated betw.en 100 and 150 a month.

The area .tudied W&l in the 'Fundo Piohun' (Pinchun eetate) on the ooastal rance of 1D0untaine at an average height of 30 ID above .ea level, near the city of Nacimiento in Provinoe of Bio-Bio. The terrain W&l in g.n.ral very roush, with alopes in some places above 30 p.roent.

The .oil. belonged to the San Eat.ban .eriee, ooming frOID granite rooke. The first 30 UII of the profile (generally the .oil. to be considered in skidding) w.re of a eandy ola,y texture, pri.matic .tructure and very plastio, adhe.ive and friable.

The work WaB b.ing oarri.d out without a apacific lDanagement .y.tem in a fore.t of radiata pine with the followinc oharact.ristic.: "e 22 y.ar., av.rag. height 30 IDI av.rage diameter 26 011; 380 trees/ha; b&lal area 46 1D3/ha; av.rage volume 448 m3/ha.

Th. dilDlDlione of the loga transported for sawing were: length 4 m, minillum diameter 18 OlD; and for pulpwood, length 2.44 m, lDinilDum diameter 10 CID, lDaxilDum 18 or 20 om.

The .yst.m Uled W&8 clear-f.lling with oontrolled fall. The .kidding area for each t.am of oxen W&l divided into stripe about 10 • wid. and variable in length.

Thi •• tudy oov.r.d 10 workins da,ys. The seven ox teams studied wer. on average .even years old with a minimum of one year'. experieno. :!.n forest work. Each ox w.ighed between 500 and 100 kg.

Skiddins of pulpwood W&l on .lop •• from 0 to -30 percent (downhill with load). A total of 19 workins oyol.s W&l distribut.d in the following wa,y: 1 to -10 peroent, 13 oyole.: -10.1 to -20 peroent, 45 oyole.: on gradient. of more than -30 peroent, 21 worldng oyole ••

11 The IRFOllSA (IndUlltriaa Fore.tal.. S.A.) IndUitrial COIIple:r:

- 37 -

In Ikidding lawlogl, 112 oyolel wlrl analYled, both up and down the Ilope. Th~ were diltributed in the following W~I a) downhill with load on gradientl of -15 to -20 plroent, 36 oyclea; -20.1 to -25 peroent, 38 cyoles; -25.1 to -30 peroent 11 oyolel' b) uphill with load on the gradientl of +10 to +20 percent, 26 oyclee.' ,

Resultl. ana!ylis and diaouesion

a) Speed and load

Table 4 ahowa the average valueB of apeed and load in Bkidding in hilly areas.

Table 4

AVERAGE SPEED AND LOAD IN UNITS AND VOLUME PER DEGREE· OF GRADIENT IN SKIDDING SAWLOGS AND PULPWOOD WITH OXEN

ClasB Degree of Speed Average load of loge gradient (om/I)

%

Trip Trip Average UnitB v~)ume without with

load load

Sawloga - 25.1 to- 30 50.72 49.48 50.10 3/)0 0.794 SawlogB - 20.1 to- 25 50.08 48.19 49.14 2.92 0.679

SawlogB - 15 to- 20 48 .• 11 42·32 45.'22 3.36 0.718 Saw 10gB + 10 to+ 20 64.58 45.88 55.23 2·00 0·386 Pulpwood "> than - 30 47.42 40.63 44~02 16.27 0·509 Pulpwood - 10.1 to- 20 65·73 37·10 51 ~41 15·74 0·509 Pulpwood 0 to- 10 72·35 42·34 57·34 13·23 0·509

The average Bpeed of the oxen when moving downhill with a load of lawloge WaB 47 om/a, and with pulpwood it was 40 om/e. The Qverage speed uphill without load in both CaBee WaB 56 om/I.

From the above it m~ be leen that th~ went faster with lawlogB. ThiB was be­oaUBe when transporting pulpwood the driverB had to handle the animale more oarefully to avoid upsetl and 10BB of time to restaok the unitB.

The apeed with load uphill on a Blope of +10 to +20 peroent was 46 om/I, whioh il oonsidered aooeptable for the volume tranlported. The average volume Wal 0.39 m3, which ia low oompared with the other oaseB Itudied, but it iB probable that increasing the volume reduoed the Ipeed.

The average load in Ikidding pulpwood almolt alw~1 hnded to be oOlllltant al­though the number of unitl depended on the unit volume. The workerl reBponlible for put­ting together and piling up the boltl were not the drivers, who generally prepared loads of 0.50 - 0.70 .. 3; for thil reason, an average was found for the three 0 ... 1 analylld.

In transporting eawloga, the driver eelected the unite and approximate .. olume to be transported. Aooording to how muoh the downward Ilope inoreased, he oould inorease the load, linoe the Iteeper the inolination the greater the effeotl of gravity and the lell effort required from the oxen.

For Ikidding downhill, the driverl did not normally reduce the volume of the load when the gradient of the Ilope increased, except in very Iteep Ilopee but experience had tll.ught them that when lk1dding uphill the load Bhould be reduoed oOlllliderab~. In thil ItUdy, the volume of load transported uphill ranged between 0.30 and 0.40 m •

- 38 -

In Ik1ddilll 101011 of rad.ia1;a pine 1;he muimum volume wsa 1 .11 .3 on a dope of -11.5 peroen1; and 1.51 m3 on an averBle .lope of -30 peroent, equivalen1; 1;0 1 809 and 1 598 q respectively 1/, hauled by a ham of oxen weigh1ac abou1; 600 q each. However, 1;his does no1; mean tha1; these are 1;he muilDUll or optialUII low in 1;h1s 1;ype of skiddilll.

b) !.!!!

Tables 5 and 6 show the 1;ime equa1;ions ob1;ained per cyole and per .3 1;0 skid sawlogs and pulpwood over differen1; 1;ypes of slope.

TIME EQUATIONS PER WORKING CYCLE IN SKIDDING SAWLOGS AND PULPWOOD WITH OXEN, BY DEGREES OF SLOPE

Class of lOIS

Sawlogs

Sawlogs

Sawlog.

Saw logs

Pulpwood

Pulpwood

Pulpwood

1; • Time, in oentim1nutes

x • D1s1;anoe, in me1;res

Degree of slope '1>

- 25·1 1;0 -30 - 20.1 1;0 -25

- 15 1;0 -20 + 10 1;0 +20

> 1;han -30

- 10.1 to -20 0 1;0 -10

Table 6

Equa1;ion

1; • 515.968 + 1.566 x 1; • 534 .951 + 1 .838 x t • 915.721 + 5.610 x 1;. 53.518 +11.112 x 1; = 313.322 + 7.182 x 1; • 294.099 + 6.812 x 1; & 251 .335 + 6.124 x

TIME EQUATIONS PER .3 IN SKIDDING SAWLOGS AND PULPWOOD WITH OXEN,BY DEGREES OF SLOPE

Clall of logs Degree of slope Equa1;ion '1>

Sologs - 25.1 1;0 - 30 T • 125.400 + 9~529 x Saw logs - 20.1 1;0 - 25 T. 181.851 + 11.543 x

Saw logs - 15 1;0 - 20 T • 145.051 + 10.196 x Sawlogs + 10 1;0 + 20 T. 138.803 + 28.943 x

Pulpwood ~ than - 30 T. 52;.125 + 12~050 x Pulpwood - 10.1 1;0 - 20 T. 493 f 455 + 11.530 x Pulpwood 0 1;0 - 10 T. 421.103 + 11.282 x

1/ 1 .3 of green rad.ia1;a pine. 1 058 kg (Ra11w~s of Chile, quo1;ed qy Pugin, 1981)

- 39 -

From Fie. 8 it ma, b ••• en that the time per oyole of .kidding on .lope. of + 10 to + 20 pero.nt wae leI. than for .kidding downhill, whioh ma, at first .ieht .... • trange. Rowev.r, when more than one .awloe waa tran.ported over .hort di.tanoe., the terminal time of loading beoame an important factor in the total time of the cyole. In the caee of a .lope of + 10 to + 20 p.rcent, the number of 10gB .kidded wal reduoed be­oause of the greater effort required from the oxen, and the terminal time to put together the two logl (the average number in the ItUdy) wae leI. than when .kidding downhill. In the latter oaae, the number of logl wae 3.36 for - 15 to - 20 peroent, 2.92 for - 20 to - 25 percent and 3.00 for - 25.1 to - 30 peroent. With a .teeper downhill Ilope, the quantity of loe. that oould be Ikidded dropped because of the ri.k involved, and therefore the total time of the .kidding oyole dropped.

5

a

17 -.. V ..

.....V 16 '---- ~. ./ 1-

L V /:

", .. 15 .,-, " V 1/ . . 4 . . .. '~- +--+--

~ ~ '2,( . . 3 IY?

~-

~ .... -

..J o~ . . 2 V ~~~Ol'

... t--t--. t-

VV .

1~- - I-. ~ ~1 ~,.~ t-- ._.- "._- -~-. , ,

Of--__ 41!!.

f-- ~ b~. r-- t--- ----. --t--~--

~ .p ••• '

9

lh V 1/' .. .. --t--f-.-t--

8

~ .",.- .. ..-

~ ", .. - - -

.' ...••..

... ....... . ...

~ 7 ..... i"' 6

-f-l-.,,-1-"" ""

.' .' .. ' ---~-- .. -- -4

3 .... 2 --f-- ..

---I-- .. f-~- -- -

00 10 20 30 40 50 60 10 80 90 100 110 120 130 140 150 16

Skidding distance in metres

Fie. 8 TIllE II MINUTES PER WORK CYCLE TO SKID SAWLOGS WITH om ON DIFFERENT DEGDES OF SLOPE

For pulpwood the lituation Wal different. The load might oonsi.t of 6 to 16 bolt. (or more) which were .0 clo.ely .tacked that when the ohain wal faatened it W&l &I

though th~ were only one loe.

Beoausl of thi., the loading time for pulpwood varied little while that for .awloe. wae more Variable, dlpending on their number and how far apart the) were.

Unloading time wae muoh leBI than that for loading. It depended on th6 .lope in the unloadilll area and the wa, the driver placed the oxen when he unfaatened the load. On level ground the time tendld to be lel8 than on Ilopilll ground. In the latter oaee, if the oxen remained facilll at right &1111 .. to the 810pe, the time wae greater than if th~ faced in the lame direotion. Because the load la, between the oxen, the driver wae much more oareful in loo.ening it to avoid the logl rolling and injurilll the animale.

- 40 -

3

~ o 10 20 30 40 50 60 10 80 90 100 110 120

Skidding distance in metres

Fig. 9 TIME IN MINUTI!:S PER WORK CYCLE TO SKID PULPWOOD WITH om ON DIli'P'IRENT DlGRIlES OF SLOPE

In practioe the drivers usually positioned the oxen in the opposite direction to the slope 10 that later the stacking would be easier because helped by gravity.

Terminal timea recorded for pulpwood bolts were between 2 and 2.7 minutes, of whioh 60 peroent was for loading. For lawlogs, they fluotuated between 2.5 and 7.15 minutes, 80 percent for loading and 20 peroent for unloading.

An analyeis of Ipeed, volume of load and terminal times plus the information oon­tained in Tables 4 and 5 makes it pOlsible to understand and analyse the times per m3 for each of the oases studied on different levels of slope, and also the behaviour of the graph lines in Figs. 10 and 11.

~

2

;z

2

2

2

I

0

19

18

17

16

15

14

3

2 I

0

9

8

7

6

.. ..-

~

I t ./ '7

V .' 7' ! /'

l/ .) /'

.... I /' ~ V 7) i

- 41 -

/ '#' ./ ~7 ~""l ......-l

..y ./ /: /' )/ ~'Z~ .... ' /' ,~V "t;) IY ./

,/ ,,/, ./ ~ ~y

/' "J ,Y '/

/'

..

~,. 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160

Skidding distance in metres Fig. 10 TIME IN MINUTES PER .. 3 TO SKID SAWLOOS WITH am

ON DIFFERENT DI!XlREES OF SLOPE

It 1183 be observed from Fig. 10 that the time per .. 3 to skid uphill is acoept­able for ahort diatancea, but aa the diatance inoreaaea the time alao inoreaaea oonaider­ably •

Developing the time equationa per work cycle and per m3, the valuea of time for different distanoea of akidding aawloga and pulpwood were obtained, and are ahown in Tablea 15 and 11 in Appendix 5.

2 0

.. III

'" ~ c: ..... e c: I .....

I I ..... ...

9

e 7

6

5

4

3

2 I

0

9

8

7

8

:.

- 42 -

./1 ",,"'.......1

~/ ./ /. ~L' .......

A ~./ ",

~ ",=Q! "'" ./ ~ ~ -"" "/"" V

V/ :,.....-~ "/

h "/ h V/

~ V ....... ~ '~ V

10 20 30 40 50 80 70 80 90 100 110 120

Skidding distance in metres

FiB. 11 TIllE IN MINUTES PER .3 TO SKID PULPWOOD WITH OXEN ON DIFFERENT DEGREES OF SLOPE

c) Output

Table 1 shows output expressed in m3/h. Replacing this by values of distance shows the output for different degrees of slope. whose results appear in Tables 15 and 11 in Appendix 5. also shown in Figl. 12 and 13.

- 43 -

OUTPUT EQUATIONS IN SKIDDING SAWLOGS AND PULPWOOD WI'l'R OXEN BY DEGRnS OF SLOPE

ClUB of 10gB Range of slope

'" Savlogs - 25.1 to - 30

Sa ... logs - 20.1 to - 25

Savlogs - 15 to - 20

Savlogs + 10 to + 20

Pulpwood ::> than - 30

Pulpwood - 10.1 to - 20

Pulpwood 0 to - 10

o - output in m3/h

x = distanoe in metres

g .... ...

9

8

4

g 3 '0 o .t 2

I

, , \

.......

~ ~,

" --.

..

lS' ["--s f.'~,L. ~ ~/--""'" ~ 'tobr--......:: ?So r------- 'i..<l -r-- -i5~~ r--2 ~o -.............

Equation

4 164 0- 515.966 + 1.566 x

4 014 o •

534.951 + 1.838 x

4 308 o •

915·121 + 5.610 x

2 316 o •

53.'H8 + 11.112 x

3 516 o • 313·331 + ·1.1~2 x

3 516 o - 294.099 + 6.\172 x

3 516 o - 251.335 + 6.124 x

...

--r---- --~ o

10 20 30 40 50 60 70 80 90 100 110 120 140 150

Skidding distance in metres

Pig. 12 OUTPUT IN '1I3/h IN SKIDDING SAWLOGS WITH OXEN ON DIFFERENT DJlGHEES OF SLOPE

- 44 -

The output in IltiddiDB lawlop uphill dear8u .. Iharply .. the diltano. i noreu 81 , the oritioal point beiDB at about 55 m.

It Ihould be pointed out that in IltiddiDB lawlogl Ipe.d of movement and volume tend to be greater than in IkiddiDB pulpwood, however, output il lower beoause more time il Ipent in 10adiDB.

oxen.

....

... :I o .c ... QI Q,

E! s: ... s: o ... ... \) :I ~ o ...

II"

11

10 ~

\ t \..

~ \\ 1 ~ ~

~ ~ 6 ' % ~

~ ~ '-5 ..... ~ ~ ~ 4

I-... ........,;:: ~ ~ to-.

:s ->

o 10 20 30 40 50 60 10 80 90 100 110 120 Cl1"it't'1". "1 IiI1:lIJIOli ift Inri"_

Pig. 13 00TPtPl' II M3fh ~ '1'0 8m PUIPtfOOD WIIJH OlD' ON DII'PiiRlIiN'1' DlXJRBBB or SLCPE

Table 8 givel the OOlt equation per .3 for IkiddiDB lawlogl and pulpwood with

- 45 -

Table 8

CasT EQUATIONS PER .3 IN SKIDDING SAWLOOS AND PULPWOOD WITH om

Cl ... D18l'.e of elope Co.t equatiolll of 101' ~

Ch,v us. Savlos. - 25.1 to - 30 C • 9.1131 + 0.1216 x C • 0.1120 + 0.0015 x Savlog. - 20.1 to - 25 C. 10.5493 + 0.1546 x C • 0.1211 + 0.0018 x Savlog. - 15 to - 20 C • 11.0113 + 0.1046 x C • 0.1910 + 0.0012 x Savloga + 10 to + 20 C • 1.8586 + 0.3815 x C • 0.0214 + 0.0045 x Pulpwood "> than - 30 C • 1.0395 + 0.1614 x C • 0,0812 + 0.0019 x Pulpwood - 10.1 to - 20 C • 6.6014 + 0.1544 x C • 0.0162 + 0.0018 x Pulpwood 0 to - 10 C • 5.6466 + 0.1511 x C • 0.0651 + 0.0011 x

Coat equations &I " function of diatanoe and alope are ehown in Table. 16 and 18 in Appendix 5, and in Figa 14 and 15.

11 US, 1 • Chi 86.10 (16 December 1983)

Ch $ 30

9

8 7

8

2

2 2

2

2

2

2

2

2

2

5

4

3

2

I

° 19

18

17

16

15

14

3

2

II

10

9

8 7 ""IIi >

V V !

/' l , - ;/

/

II 7 / 1/

./ "... .. ,.~ .

Vl , , . :

I -

.. -.. -, ....

--.

- 46 -

J

J ./ / ./

t"l ./ I' / ~If .O~ V'" /

_0'1 ,~ .\fLO /'

10/' 7 ~ / 'r ,/ .n~ V

;~ 7' 'T / ~V

/ 7 / /

V / -1

-'"

. -- .-... ~- _ ..

.. -

..

.~.~_M - ..

A ./ V '/ ~

/ /

...

-.

-.

L /~

V

./

US $.1/

0,35

0,33

0,32

0,3'

0,30

0,29

0,28

0,27

0,25

0,24

0,23

0,22

0,21

0,20

0,'8

0,'7

0,16

0,15

0,14

0,13

0,12

0,10

0,09

0,08

10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160

Skidding distance in metres

PiS. 14 COST P!R m3 IN SKIDDIRG SAKLOOS WITH OXEN Ii RELATION TO SLOPE AND DISTANCE

11 USI 1 • ChS 86.70 (16 December 1983)

Ch 2

2

2

$ 2

I

° Ie 18

17

16

IS

14

13

12

11

10

9

8

7

6

5

':;:.

/. ~/'

/'/ /' /~/

//' /' 'l /' ./

- 47 -

./ ~/

17 ~/ .~ ~I' V-

l-roV" ,y.-'

/. 79-" / '/ /'

// /' // /

/' / /'

/~ / / / /'

/ /'

us $!I 0,2e

0,24

0,23

0,22

0,21

0,20

0,18

0,17

0,16

0,15

0,14

0,13

0,12

0,10 opg 0,08

0,07

0,06

0,05

° 10 20 30 40 eo 60 70 80 90 100 110 120 130

Fig. 1; Skidding distance in metres

COST PER .3 TO SKID PULPWOOD WITH OXEN IJ RlLATION TO SLOPE AND DISTANCE

2.6.1.2 Skiddins on level ground

The area atudied was on the Trilahue eatate in the Valle Central between the oitiea of Loa Angelea and Cabrero, Provinoe of Bio-Bio.

The eatate was 125 m above .ea level. The land was generally flat, with alopes no ateeper than 3 peroent. The predominant soila were aandy, belonging to the 'Coreo' seriea, of andeaitio-basaltio origin, with fast or excessive drainage and low water re­tention. The profile from 0 to 23 om had a struoture of aingle partiolea, looae when dry, non-plastio and non-tacky when wet (Chile/OAS/rDB, 1964).

The Trilahue eatate was an area belonging to a foreat enterpria~ whioh in 1982 owned directly or indirlotly 140 000 ha of plantationa of radiata pine. It extracted ap­proximately 1 900 000 mj of timber a year, lome of it exported as loga, .ome aupplied to other enterpriaea produoing pulp and paper, and to the dome.tio market for aaw-wood and fuel. Where data on skidding pulpwood and aawloga were oolleoted, skidding was, in view of the topography (level), entir.ly with oxen. On other e.tatea belonging to this enter­priae, skidding was done with fore.t wheeled tractor., oxen and hor.es.

Skidding was .tudied over six working daya, using three ox teams. On aver/l&e, each ox was eight yeara old, weighed 650 kg, and had a minimum of two year.' experienoe.

11 US, 1 • ChS 86.10 (16 December 1983) 1I Fore.tal lininoo S.A.

- 48 -

The apeoitio lituationl atudied were: akidding pulpwood atter thinning, vith 66 work oyolea; akidding of pulpwood atter olear-felling, with 56 oyolea; and akidding of aawlogl atter olear-felling, with 54 work cyolea.

Skidding of pulpwood atter thinning wae, ae ita name indioatea, in a atand where atunted and .edium-aized treea of little importance for the atability ot the foreat had been thinned. The foreat vae approximately 16 yeara old, with 1 800 treel/ha and 400 m3/ha. The intensity of extraction waa about 800 treea/ha and the approximate volume 85 .3/ha. The length of bolts transported wae 2.44 m with a minimum diameter of 10 om.

Information waa allo oolleoted on skidding pulpwood in a Itand 19 years old, with 1 213 treea/ha and an approximate volume of 518 m3/ha. The bolts transported had a minimum diameter of 10 om and minimum length of 2.44 m.

Transportation of aawloga vaa alao atudied in a forest 19 years old. with 1 662 treel/ha and an approximate volume of 518 m3/ha. The logs transported had a minimum diameter of 26 om and minimum length of 4 m.

Results, analYais and disoussion

a) Speed and load Average speed and load are shown in Table 9.

AVERAGE SPDD AND LOAD IN UlfITS AND YOLtlD, IN SKIDDING SAWLOGS AND PULP'iI00D WI'!"1 om ON LEVEL GROUND WITH DIFFERENT FELLING SYSTF.:MS

Claas Felling Speed Average load of loga aystem (om/s)

Trip Trip Average Units Volume without with (m3)

load load

Savlogs Clear-felling 56.58 36.54 46.61 1.00 0.411

Pulpwood Clear-felling 68.11 51 .48 59.19 5~18 0·361 Pulpwood Thinning 16.16 54.58 65.61 11.12 0.289

On level ground oxen made better speed on trips without load oompared with their apeed on ground with a positive slope. For trips with load the speed dropped, mainly beoause of the effeot of friction, in comparison with the loaded trip downhill.

Similarly, load volumes skidded downhill were greater than those skidded on level ground.

The average load volume of thinning waa lower. beoause the trees thinned were of low volume oompared with the average volume of trees in the stand, and the stacKed and skidded loada were equal to only one tree. It would have meant a loss of time for the stacker to oolleot together in the same loading place thinnings equal in volume to two or more trees whioh, beoause of the felling oonditiona, were far apart. It would also have meant a loss of time for the driver to oolleot the logs of various trees to transport them in one trip over a short distanoe.

b) !!!!!!

The time equations per oyole and per m3 for the three typea of skidding studied are shown in Table 10. The values of their development aa a funotion of distance are are ahown in Table 19 in Appendix 5 and Figs. 16 and 11.

- 49 -

Table 10

TIllE EQUATIONS PER WORK CYCLE AND PER .3 IN SKIDDING SAWLOGS AND PULPWOOD OK LEVEL GROUID WITH DIFFERENT FELLIKG SISTErS

Clus Fellill8 Time equation Time equation of logs system per work cycle per m3

Sawloga Clear-f'elling t _ 108.233 + 6~824 x T - 259~552 + 16.364 x

Pulpwood Clear-felling t a 223.900 + 3,948 X T "' 610.082 + 10.757 X

Pulpwood Thinning t - 281.569 + 3.850 X T • 974.287 + 13.322 x

6

Q, .... .., ., .., C ::J 0 .., .., Qj Q,

., Qj ., ::J C .... E C .... Qj

E .... I-'

Skidding distance in metres

Fig. 16 TIME IN MINUTES PER WORK CYCLE TO SKID SAWLOGS AND PULPWOOD WITH OXEN ON LEVEL GROUND

The terminal timea for loading and unloading in the three types of skidding were relatively short. Averages recorded were: 1.80 and 1.50 minutes for pulpwood after thinning and clear-felling respeotively, and 0.80 minutes for aawlogs, or 64.37 peroent, 63.35 percent and 60.50 peroent, in that order.

In skiddill8 sawlogs, terminal times were shorter because there was lesa handling of units, only one log being transported per trip. But in akidding pulpwood after thin­ning, where the average load was 11.72 unite, the driver spent more time in fastening the load to prevent its working loose with movement. This led to an inorease in time per work oyole and per m3• The oonsiderable volume of the load transported should be noted.

The d1tferenoe in time pel" oyole for pulpwood atter th1nnillB and after olear-fellirJg were appreciable in the total time necessary to oollect 1 m3 from different diatanoes. Also, the speed developed qy oxen in akiddillB pulpwood after thinnillB ~u higher. How­ever, if volumes per load are low, the time necessary to tranaport 1 m3 will be greater and output will drop.

- 50 -

20

19

18

17

16

15

14 III I» jj 13 ::I c

--- r---

L ----- r-------- --- V'

L ---- --- --_ .. _-- r-----1--------- -----" ~ L - '-----"-t-----. r---' -- r-; {\~

\,{\{\'> ~"\\ ----r-p ~~e

----,,- 00-1------ 00

~ ~:--1------_.--r------- --t--~ ...

12 e s:: ...

"

A ./ --. ---~::~ ... {\~ ,

--r--'-'-- \e I» e ... 10

'"' 9

8

7

6

5

c~ ~te<C \\{\ 00- ':\,e\

~oo ,. y\}w \e0-'<

~--

V ~~--~ ~

r -F-------1-- .. _-_.-

L -- .. _-----

o 20 30 40 50 60 70

Skidding distance in metres

P' P1,.. 17 TIME IN IINUTES PER .3 TO SKID SAWLOGS AND PULPWOOD WITH OXII Olf LmL GROUND

0) Output

Output equationa expressed in m3/h are shown in Table 11; by introducing the dis­tance, value. were obtained for the three skidding systems shown in Table 19 in Appendis 5 and Fig. 18.

M e c: ..... c: o ..... .., U ::l

"0 o ~

Po.

- 51 -

Table 11

OUTPUT EQUATIONS IN SKIDDING SAWLOGS AND PULPWOOD WITH OXEN ON LEVEL GROUND WITH DIFFERENT FELLING SYSTEMS

C lase of loge Felling syst. Output equation

2502 Sawloga Clear-felling o •

10ts.233 + 6.ts24 x

2202 Pulpwood Clear-felling o •

223.900 + 3.948 x

1734-Pulpwood Thinning o.

2B1 .569 + 3.B5 x

2

1 ~ \

0

,,~ 9

~ ~o,\' e

~ p~J ~~ ~o c,

7 o~ ~~

OFt ~ er- ~ ~ III

8 ilr-"'Eelli '{f

--~ ~ 15 • PUl

-~ --&Eter r-----~i1111 118 4 --~

3

<i> 10 20 30 40 50 80

Skidding distance in metres Fig. 18 OUTPUT IN 1D3/h IN SKIDDING SAWLOGS AND PULPWOOD WITR OXEN

ON LEVEL QROOO

70

- 52 -

The best output obtained on level ground waa with sawlogs. This waa due mainly to the greater volume of load and lower number of logs transported.

Output after thinning waa low beoause of the Wa.Y the forest waa ez:ploi ted, namely, selective felling. The small volumes of the tre .. affeoted output. It should, however, be pointed out that in this type of exploitation animals are extremely useful beoause they are e&8Y to manoeuvre, even when the forest is denae.

d) Q.2!!!

The oost equations per .3 for skidding with oxen on level ground are shown in Table 12; they were developed to provide the values for the different felling systems that appear in Table 20 in Appendix 5, on the basis of which Fig. 19 was prepared.

Ch $ 5 4

3

2

I

2

2 2

2

2

20

9

18

7 8

8

4

3

2 1

0

e 8

7

.: ~

./

~ V

t.\\\.~

tt.e" ;;...-'" ~oo~

'l~y ., --te\~ .."

c\!yLQ./ ;t~ ~

000 • t e\ 'l~\9~ \e.~ ~ e"Y-

~¥ ~Y;P

.7 ,

./ ./"

-? ..........-/ V

......-I ~

.... _--

"7 ~

US $Y 0,2S

0,28

0,27

0,25

0,24

0,23

0,22

0,21

0,20

0,18

0,17

0,16

0,15

0,14

0,13

0,12

0,10

0,09

0,08

0,07

o 10 20 30 40 so 60 70

Skidding distance in metres

Fig. 19 OOST PIR .3 IN SKIDDING SAWLOOS AND PULPWOOD WITH OXEN OM LEVIJ.. GROm

11 US, 1 • ChI 86.70 (16 December 1983)

- 53 -

Table 12

COST EQUATIONS PER 113 IN SKIDDING SAWLQGS AND PULPWOOD WITH OXEN ON LEVEL aRcmro WITH DIFFEmT FELLING SYSTIIS

Class of logs Fell1l1B system COlt equatioIIII

ChS USslI

Sawlogl Clear-fellillB p • 3.4764 + 0.2191 x C • 0.0401 + 0.0025 x

Pulpwood Clear-fellillB p • 8.1690 + 0.1440 x C • 0.0942 + 0.0017 x

Pulpwood ThinnillB P . 13.0457 + 0.1784 x C • 0.1505 + 0.0021 x

Production COlts were considerably higher with thinnillB than with olear-fellillB, and were lower for skiddillB lawlogs.

2.6.2 Skidding in natural forests

Because of the conditioDl in natural forests as regards location, topography, dispersal of the species to be extraoted, density of the forest, volume and weight of the logl, and because of the distances to be covered, skiddillB with oxen is specially suited to this type of work.

The paths used for skidding are seldom properly prepared; they are narrow, with branches, roots, stumps and other obetaoles that make skiddillB difficult. The slopel of the paths are variable and steep, sometimes up to 60 percent.

When the slope changes, from ascendillB to delcending (usually a very short sec­tion), or when a steep slope becomes gentler, the driver should shorted the traoes (or chains) to make better use of the power produced by the cxen. In skiddillB downhill over very steep sections, the traoes should be lengthened to prevent the logs from bumping against the hind legs of the oxen and oausing them injury; in some cases, the force of gravity causes the logs to move faster than the oxen (lee Fig. 20, sections aa and bb).

On the buh of a technioal report prelented in 1980 by the Complejo Foreltal y Maderero of Pansupu11i y and oonveJ'llationl with driver. in the zone, lkidding diltanoel of up to 1 500 m and an aver. distanoe of 700 m were determined. Thil wu largely due to lelective exploitation of Ipeciel whioh veri far aWil from the lan4ingl and the main roadl and therefore involved llci.dd1ng over long diltano.l. In 1980 the volume of timber moved in the Complex wu 83 000 1113, of whioh 31 000 m3 were Ilci.dded with oun and 52 000 m3 with whe.led forelt tractoJ'll IUId orawler tractOJ'll. Of thil latter volume, 31 000 m3 were moved with oxen to "lilt the tractore. For lkidding the volume mentioned above, a total (If 124 taUlS of oxen waB uled, whioh provided an aver. output per telUJl of 3.25 nI3/day, 75.5 1\3 a month and 500 113 a ;year.

11 USS 1 • ChS 86.70 (16 Deoember 1983) 1I An area of natural forelt in the Prcvince of Valdivia, oovering about 240 000 ha, of

whioh abcut 50 percent il productive. In Ncvember 1983 there were two fixed lawmille with bu4 I", two portable 1&1l1li1111, three fixed la_UI with oircular law, IDd on. P11VOod faotol'1. all IlIIIll iutallationa.

.... QI

410

400

390

380

0

~ 340 .... ."

~ 330

QI

> .& 32 ." ..,

..c:; 31 co .... QI

0

0

::c 30 0

29 0

28 0

27 0

- 54 -

0

o~ ~

~ .... ~

~

"'[\.

"~ ~

"0 a v \Y\o.

b

~ ""

.- "-"~--,~ ----~ D

b

o 100 ISO 200 2:10 300 3:10 400 4S(

Skidding distance in metres

Fic. 20 PROFILE OF A PATH USED FOR OXEN SlCIDDIliG IN MATURAL FOREST

Kent ion should be made of a type of skiddill8 known as worlc .... haring that usee tvo or more ox-teams to haul a log when its weight and volume are too great (usually, above 1 300 leg) for one team to handle.

One technique in work-eharing involvee placing tvo pain of hoob into the front of the log with one pair on top and the other underneath. The upper pair ia dracged by a t .... of oxen with a ahort trace in order to rai .. the lOB llightly. The lover pair is pulled forward with a longer trace by one or more other teama (aee pbotOBrapha).

Skidding with oxen in natural forest, using the work-sharing system (Neltume, Chile)

Log skidded b,y the work-sharing method, with chains with hooks attached to the front (Neltume, Chile)

- 56 -

Beoauae of the oondition! outlined earlier, skidding in natural forest muat be downhill; the drivers must bs experienoed; and whenever possible two or mors ox-team. should work on the same skidding path so that they oan help eaoh other by work~haring when the a1tuation so requires. Beoauae the work is so hard, working time per da.r should bs five to six hours, allowing the oxen a good rest period.

2.6.2.1 Conditions of the study

Skidding with oxen in natural forest was studied in a looation of the Provinoe of Valdivia, in the Andea. The altitude ia approximately 400 m above sea-level and the topograph,y very rugged. The aoils in the area belong to the Malihue series; they are sandy ola.r, with moderately fine textures up to 65 om, 10088 on the surfaoe and slightly hard to hard in depth, friable, slightly plastio and slightly taoky (IREH-UACH, 1978).

The work studied was in a foreat past maturity, owned qy a foreat enterpris.1l. Extraction was seleotive, of speoies with high oommeroial value: ooigue, (NothofaguS domb!yi), laurel (Laurelia sempervirens), lingue (Persea lingue), olivillo (Aextoxi­con punotatun), tepa (Laurelia philippiana), tineo~ania triohosperma) and ulmo ~oryphia oordifolia).

Distribution per ha of trees with a d.b.h. of at least 40 om was as follows: tepa, 6; ulmo, 2; ooigue, 3; olivillo, 3; others (man£o, oanelo, laursl, rOble) 8-10.

The logs skidded had well defined dimensions depending on the use to be made of them. For sawing they had to be 3.60 m long with a minimum diameter of 0.30 mj for veneer produotion 2.80 m long with a minimum diameter of 0.48 m.

At the time information was oollected for this study there were 30 ox-teams. Of these, four pairs of anlmals with a weight of approximately 600 kg each were studied. The drivers had more than five years' experience. Work was analysed over five ~s in which 23 working oyoles were recorded over a maximum distance of 460 m.

Skidding with oxen in natural forest (Neltume, Chile)

11 ~SIL, an enterprise oonsisting of a plywood plant with a produotion of 300-350 m /month, and a sawmill produoing 670 m3/month. (Information supplied qy GermAn Oettinger, forester).

- 57 -

The sltidding patha were narrow and in most oues obstructed by roots and branch ... The average slope of the paths fluotuated bstween -20 and -32 peroent (downhill). On some short seotiona Ilopel of up to -60 peroent were .. lUured.

Resultl, ana~sis and disoUision

a) Speed and load

The average speed of the oxen for the idle trip wu 0.43 m/s, and for the trip with load 0.40 m/I.

T~e average load w .. 1.19 .. 3, equivalent to about 1 268 ki.1I The maximum load reoorded was for a ooigue (NothofaguS domb!yi) log, 2.64 m3, whioh is equivalent to 2 905 ki or 1 453 ki for eaoh ox. Theae volumes m~ be oonsidered very high, but they are not altogether Burprieing as the steep Blopee made ekidding easier.

b) .'ll!!!

The time equation per work oycle was found .. a funotion of diBtanoe, and the time per m3 aB a function of distance and average volume of load.

t - 446.138 + 5.130 x

T - 218.313 + 4.322 x

where: t - time per work cycle ~

T - time per m3 ~ x _ distance in metrea.

Some time values for different akidding diatanoea, baaed on development of the above equationa, are shown in Table 21 in Appendix 5 and in Fig. 21.

11 The denaitiel ueed to oaloulate the average weight of the load were,based on those luggelted by Torrel (1971) (in t/m3): ooigue, 1.10;laurel, 0.99; llngue, 1.09; olivillo, 1.00; tepa, 1.00; tineo, 1.10; ulmo 1.18.

g/ Tille valuel expresled in oentiminutes

III

• 8 7

6

5

5 5

5

5

5

5

4

5

5

5

5

2

I

0

\\I 2 e ... g 2 8 ." e .;<

27 26 5-

4

2 5

2

I

2

2

2 0

9

8

7

6

a 4

!~

t-.,

.L IL

- 58 -

- ··t- .. r-g -r-f- - r- . -~ - . -_ . t7

t-- -t-' ,. .... - -V .

V .. - .,

'" V ., -

II - - _. ... .- g - II - 1-- -~ 1I -r--t- 1/ .LV f-1-"

r-'r- . 1/ /

. c>~ 1/ .. .-. -~ V ~ ~ ,i'L '\;<-/ r- .. '-t- --

'II"'L ~'II Z ...,c,~ .~'II ",'0

~ C,L " r-r- ~

./ #'. q;Lr-r- .- . ,,' .. ,-- . . ., .. - r- -/ '\~~

-'- ~ V .. - . .• f-" " f--- f-- -

V

" .- ,---- - f-

r' ..

...

-

100 200 300 400

Skidding distance in metres

Fig. 21 TID II lINU'l'ES PER WORK CYCLE AND PER m3 FOR SKIDDING WITH OXII II NATURAL FOREST 01 SLOPES OF -20 TO -)2 PlRCINT

or the total time recorded 71.52 peroent oorreaponds to time for the work oyole proper, apportioned aI followa: trip without load, 28.72 peroent; loading, 14.93; trip with load, 30.58 peroent; and unloading, 3.29 peroent. (The average actual time of load­ing Wal 3.39 lIinutea, and unloading, 0.18 minute •• ) COIIputable .upplementary time ac­oounted for 22.48 peroent whioh Wal apportioned aI follow.: 10.05 peroent in rest for the oxen, 8.84 peroent in lengthening and ahortening the tracea, and 3.59 peroent in removing branohe. and other obatacles.

The time breakdown giv ••• ome idea of the hard work oarried out by oxen in nat­ural foreet, where the animals have to re.t repeatedly to avoid extreme fatigue.

0) OUtput

The output equation e.tablished in this stua, Wal aa a funotion of the skidding

- 59 -

di.tano. and the volume of load, uaing an average volume of 1.187 m3 for all work CI01 ... It i •• xpr •••• d .. followa:

n _ 1 122

446.138 + 5.130 x

wh.re: o. output in m3/h

x •• kidding diatanoe in metres.

Valuea of output based on the above equation are shown in Table 21 in Appendix ~ and Fig. 22 il allo baaed on them.

.... :> o

b

..c:: 4 .... <II Q.

)

e .~ 3

!: o .... .., o :>

'" e 2 Po.

o o

.-'--.. ---

\.

" .-

'~ ~ .--.,

100 200 300 400 Skidding distance in metres

Fig.22 0CJIl'PU'l' IN m3/h FUR SKIDDING Wmi <KEN IN NATURAL ~'l' ON SLOPPZ OF -20 'l'O -32 PERCERT

The e.timatea of output over different distanoe. rerer exolusively to time taken in skidding prop.r and do not includ. time apent stacking or loading trucka, although the oxen often oombine akidding with these jobs. The output per hour for a distance of 460 m was 1.81 m3•

d) OOltl

The COlt equations obtained as a funotion of volume and dietance were as followa:

o (m3) • 15.9112 + 0.0564 x (in Ohl)

o (m3). 0.1835 + 0.0001 x (in USl)

wher.: 0 (m3) • OOlt in ChS or in USI

x • Ikidding diltancs in metres.

- 60 -

Table 21 in Appendix 5 ahowl the ooata per .3 in Chi and in USI for different akid­ding diatanoll, and Fig. 23 givel a graph of the ooatl.

The hourly ooet of ekidding with oxen in natural forelte inoludel the OOlt of the hoou and ohain used for log transport, but doel not include the value of normal or Ipaoial feed per d83 linoe oxen doing this type of work are allowed to gra.e freely around the forelta. For thil reaeon the hourly OOlt ie lower than that in radiata pine forelte.

It ie not usual to ekid over ehort distanoe in natural forests; in general, the minimum ekidding distanoe ie 200 m, giving a value of Chi 21.19!m3, equivalent to USIO.31. The oost per m3 of Ikidding for 460 m ie Chi 41.85 or USI 0.48. 11

Ch $ us $11

~~r-~~r-r-~~~~-'-'~~~~~-T~~-r-r-~Ij~~a

41 I--+-.... -I--~~~H--I--· +-+-+-+-+-+/--11'4 0,47

40 1--+-1--1--1-- -4-+-+-+-+--t-4"-4~ .. "+ " 0,46

39 - 1-" - -- -- ._- --+A-i--t---! 0,45

38 0,44

371-+-+-+--~·i--HHH--1-++-+-+-+-+-+-·tt 0,43 361-1- " ._1--1- - I-- -- --V """ " " .". 0,42

3S V- f-I--~f- 0,40

~ ~ ~9 ~ ~ 32 j 0,37

31 "/ 0,36

30 0~5

281--+-1--1--1--1--,- I-- --l----+---+--I7,.,tj--+--I--I-+-+-+-+-+-+-+--l 0,33

211--1--1-+-·- ".... " "11 0,32

27 / 0,31 281--~--+-+-- -- - 1/ 0,30

~ 1/ ~9 M / ~ u ~v

i 22 O,2S

21 V 0,24

20 1/ 0,23

1.,t--+--f-V*-+--I-+-+-+-+-I---<H---I-+-+-+-+-!--+-++-~ 0,22

1~ 0,21

o 100 200 300 400

Skidding distance in metres

Plg. 23 COST PER 113 TO SlID WITH om II lIATURAL POREST Olf SLOPIS or -20 to -32 PERCENT

11 USI 1.00. Chi 86.10 (16 Deoember 1983)

- 61 -

P.Alf.l' III

SKIDDIIO VIm AGRICULroRAL TRAC'fORS

Skidding with an agrioultural traotor and winoh

- 62 -

3.1 BACKGROUND

Agrioultural tractora are a multipurpoae tool with many applicationa, partioularly in aoil preparation and, to a amaller extent, in eowing, working on graaalande and trana­porting loade with trailer ••

Transporting loga with an agrioultural tractor and trailer: (San Ignacio de Palomarea, Chile'

In the foreatry aeotor, agrioultural tractors are used as a means of transport and for ekidding in plantations. For the latter a winoh i8 needed, driven by the tractor'. power take-off. There are very few agrioultural tractors with this equipment in Chilei they are used mainly by amall enterprisea and sawmills.

3.2 CONDITIONS OF THE STUDY

The etudy was made in a radiata pine forest in the neichbourhood of Lastarria, in the ooastal mountain range at an altitude of 441 m above sea-level. Topography was un­dulating and uneven. The aoi18 belonged to the Santa Barbara aeriea, oharacterized from 0 to 25 om by being sandy, very fine, slightly plastic and slightly tacky (Chile/ OAS/IDB/1964).

The foreat was an untended (not pruned and thinned) atand, 32 yeara old, with an average height of 35 m, average d.b.h. of 48 om and denaity of 680 treea/ha. Clear­felling waa practiced.

Skidding waa of loge 2.80 to 3.60 m long and entire treea 22 m long with a mini­mum diameter of 20 om at one end.

Skidding Waa downhill on an average alope of +5.85 peroent and over a mazimum dia­tanoe of 10.. The patha had not been laid out beforehand, nor were th~ given any kind of maintenanoe.

The tractor had no ballaat (that ia, a weight usually placed on the rear part,

- 63 -

either on the ohaasil or on the driving wheell). For thil re88on, when very heavy loada, espeoial~ whole trees, were pulled, the traotor rose on its baok wheels and sometim .. tended to Ikid.

Information for the etudy wae oollected over five working daJI, in whioh a total of 83 work oyoles was recorded, the lample being etatistioally representative. The trac­tor driver had leven years' experienoe and the ohokerman three years.

3.3 TECHNICAL CHARACTBRISTICS OF THE TRACTOR

(Make _ Universal, model U-650 X, medium power)

3.3.1 Dimensions and oapabilities

Total height - 2.42 m

Total length - 4.20 m, from the front of the front wheels to the back of the back wheels

Width - 2.05 m meB8ured over the outside parb of the rear mudguards

Weight - 2 980 kg

Minimum turning radius - 3.4 m with a wide gauge front axis

Traotive power - 1 700 kgf, with 20 percent skidding (oheoked on stubble of ground)

Speeds for one turn of the axis of the orankshaft of 1 800 rpm - (1) 2.58 to 3.83 .km/h; (2) 4.16 to 6.16 km/h; {31 5.78 to 8.56 km/h; (4) 7.68 to 11.38 km/h; (5) 18.18 to 26.94 km/h

Model - D-110

Type - Diesel, 4-stroke, with direct injeotion

Nominal oontinuous power - 65 hp

Turn of orankshaft for nominal power - 1 800 rpm

Moment of engine for nominal turn - 25.8 mkgf

Maximum moment of engine (for 1 250 rpm) - 29.5 mkgf

Number and position of cylinders - 4 vertioal oylinders in line

Diameter of the oarriBoie - 108/130 mm

'rotal cylinder oapacity - 4.76 lUres

3.3.3 !!!:!!

Front - 6.50 - 20

Rear - 14.0 - 38

3.3.4 Hydraulio system

Pump modal - FS-PR3

Pump pressure - 100 kgf/om2 (minimum) and 130 kgf/cm2 (maximum)

Pump flow - 40 litres/minute

3.3.5 Powsr taka-off

536 rpm for independent taka-off; 161.2 - 238.5 rpm in first gear; 260 - 385 rpm in 8800nd gear, 359 - 534 rpm in third gear.

3.3.6 ~ This is mounted on the rear of tha tractor. Xeohanical operation is produoed

directly by the power take-off, whioh turns olookwise and can funotion independently of

- 64 -

the tranlmislion or Iynohronized with ths tractor's speed of movement.

Skidding with an agrioultural tractor uaing the upper pull~ of the winoh (Laatarria, Chile)

SId441ng with aD lCrioultur&l '\no'\or, ua1ng the winoh drum (Lu,\alTia, Chile)

Ensrnally, the alddding equipment oonsiata mainly of an upper ateel pulley, 8 inchel in diameter, whioh allowl Ihort logs to be skidded without friotion on the ground, i.e., IUlpended (aee photograph); and a lower winoh drum, 18 inohea in diameter, driven dirlotly bf the poWer take-off. U.ed to wind in the cable, its main function ia to drag the log up 011 to the rear of the tractor 10 that the trip with load. oan start. The winoh drum is Uled slpeoially in akidding logl longer than 3.60 m (aee photograph).

- 65 -

3.4 RESULTS, ANALYSIS AND DISCUSSION

3.4.1 Speed and load

The speed reoorded without load waa 0.72 mis, with load 0.68 mi •. The averBie volume of skiddill8 per work cyole was 0.69 m3 and the maximum load waa

2.18 m3, weighing 730 and 2 306 kg reepective~. 11 3.4.2 !!!!

Of the total time recorded, 11.74 peroent was oomputable supplementary time whioh waa spent mainly in removing obstacle. from the track, and makill8 mechanioal ad­justments. The work cycle took 88.26 peroent, apportioned as fcllcws: trip withcut lcad, 15.39 percent; loading, 49.12 percent; trip with load, 16.20 peroent; unloadill8, 7.55 percent.

AverBie loadill8 time was 2.87 minutes, which was relative~ high compared with the other moments of the oycle. Loading time was reckoned from the moment when the tractor was parked to the moment when it started moving with ths load, and it could not start until the log had been hauled (perhaps 20 - 30 m' and then winohed into loaded poeition.

The time equationa, including oomputable supplementary times, found qy means of minimum squaree are aa follows:

t • 531.111 + 1.408 x

T. 614.464 + 1.628 x

where: t • time per work oycle in hundredths of a minute

T • time per m3 in oentiminutes

x • logging distanoe in metres.

The time equstion per work cyole is a funotion of the distanoe, and that of the time per m3 is a function of the distanoe and tte averBie volume of load.

Respeotive times are obtained qy replacing values of dietance in the above equa­tiona, .ee Table 22 in Appendix 5 and in Fig. 24.

11 1 .3 of green radiata pine weighs 1 058 kg (State Railway. of Chile, quoted by pugin)

- 66 -

er-----~------~------~----~------~----__,

on QI ... ::I C .... e

7~-----+------~------

c 6~-----+------~~ ....

sr------+------1-------r------+------1------,

20 30 40 so 60 70 Skidding distance in metres

Fig. 24 TIME IN J(pruTJi.:S PER WORK CYCLE AND PER .. 3 TO SKID WITH AN AGRICULTURAL TRACTOR ON SLOPES OF +0.15 TO +9.38 PERCENT

The tim .. per work oyole to akid diatano .. of 20 and 10 m were 5.60 and 6.30 minute. reepeotivel1; and the time. per m3 were 6.41 and 7.28 minute. for the .ame dia­tanoea.

The output equation ia ae folloWl:

5 190 o • ~:=;~=;==:~=

531.·511 + 1.408 %

where: 0 • output in .3/h

x • akidding diatanoe in metre ••

Output for different dietanoe. ia ehown in Table 22 in Appendix 5 and in Fig. 25.

- 67 -

'0r-----~----~----~----~----~--~ 10< ::I o

..c: ... ~8r_----_t----·~~~~--+_----_+------~----~

.., e s:: .... s:: .~ 8 ~--_+-----+_---+_----_+---_+--_I OJ U ::I

't:I o 10< ~

20 30 40 60 70

Skidding distance in metres

Fig. 25 OUTPUT II m3/h TO SKID WITH AX AGRICULTURAL TRACTOR 011 SLOPES OF +0.' 5 TO +9. 38 PERCENT

For skidding distances of 20 to 70 m, the output per hour Wal 9.27 to 8.23 m3•

3.4.4 ~

The basio information for oaloulating the oost of skidding, aI regards both the labour foroe and the tractor, brousht up to date to Deoember 1983, will be found in Annax 8. The equations obtained are as follows:

C (m3) • 67.400 + 0.1785 x (in Chi) C (.3) • 0.7768 x 0.0021 x (in USI)

where: x • skidding distanoe in metres

- 68 -

Chp 80

7g V V 78

V

0,91

0,90

77

.IV 76

V

0,89

0,88

/ 75 V

0,87

7 0,85 4 / V

/ 3 --,-7 0,84

2 /

~-7 0,83

1 -- ._--7 0,82

0 7 0,81

> 20 30 40 50 60 70

Skidding distance in metres

FiB. '-6 !'lOS'l' Pl1lR 1li3 TO SKID WITH AN AGRICULTURAL TRACTOR ON SLOPES OF +0.1 5 to +9.38 PBRCENT

The ooata per .3 in Chilean peeos and US dollars for the distanoes recorded in the study are shown in Table 22 in Appendix 5 and in Fig. 26

The oost per .3 to skid with an agrioultural traotor for a distance of 20 to 70 m was between Chp 70.97 and Chp 79.89, equivalent to US, 0.82 and US, 0.92 reepectively.

11 US, 1.00. Ch pelos 86.10 (16 December 1983)

- 69 -

PART IV

CONCLUSIONS AND RECOMMENDATIONS

From both the hohnioal and economio pointe of view the reeulte from ekiddiq with oxen have been eo good that Chilean foreltry enterprilel with a large produotion oapacity oan meet a great part of industrial needa by ulinc theee draUlht animale.

The Ikiddinc equiPllent used with oxen 11 familiar to the people and wi thin reach of thoee with limited meane. It oan be put together by the drivere, who need to purchaee only the hook. and ohain. Bkiddinc ohaine have been used for many years with poeitive r .. ulta. They are and will oontinue to be the eSlential element in akiddinc with oxen, and althoUlh ohain oould be replaced by cables, ropes or other acoeeloriee, it haa many advantagee over the others. For example, it il easy to handle, it takes up little apace, it weighs and oostl very little, it enablee the load to be quickly fastened and unfastened, and it oan be used indieoriminately for Ikiddinc eawlogl or pulpwood (for dragging one or leveral loge of different ailes and on different types of alope).

The use of an agrioultural tractor with a winoh ie more expenaive by oomparieon, beoause of the oost of investment, repairs, fuel and lubrioants. AlthoUlh output ie greater the oost per m3 il higher, as the followinc oomparilona ehow.

The etudy ehowed that the oost per .3 USing the tractor over a Ikidding diltance of 70 m and a elope of +0.15 to + 9.38 peroent was Chp 79.89 (USI 0.92), a higher amount than with ox.n. In natural foreet the OOlt per.3 over 465 m with oxen was Chp 41.85 (USI 0.48) for a elope of -20 to -32 peroentj in plantations of radiata pine, the ooet working Uphill (leaat satisfactory w~ of Ikidding with animall) over a distanoe of 80 m, was Chp 32.86 (USI 0.38). Chokermen were not used in skidding with a tractor, whioh oan del~ loading and has a marked effeot on the time of the oyole primarily due to the short ekidding diltanoee etudied.

The maxilllum ekidding load with oxen was reoorded in natural forest, where a ham weighing apprOXimately 600 kg each hauled downhill, on an average slope of -31 peroent and over a distanoe of 138 m, a load of 2 905 kg, approaching two and a half timel their own Weight. In normal oonditione in plantations of radiata

3pine, the weight skidded

downhill by a team of oxen is 529 - 1 058 kg (0.5~ - 1.00 m). In ekidding uphill, the weight of the load is 317 - 423 kg (0.30 - 0.40 m). In natural forest the weight per load is almost alw~s more than 1 000 kg.

Skidding with oxen ehould, as far as polsible, be downhill, whioh meane leee fa­tigue and longer useful life of the oxen, Ireater output and lower ooets. The prinoipal oonetraint on ekidding uphill ie the oonetant fatigue of the animale and neoeeearily low volume of load, resulting in a lower output, whioh drops even further with dietanoe. Skiddinc uphill ehould be avoided as far as poseible and if it must be done, it ie ad­vilable only over ehort dietanoes on maximum elopee of 20 peroent. It is alao recommend­ed that oxen ehould not be worked on marlhy ground, einoe the weight of the ani male plus that of the load make lIIovement diffioult.

In are .. where topographioal oonditione do not allow machines to enter to extract timber, oxen are the eolution, and althoush tit yisld ie not very high, for many people with limited reeouroee their usa provides a meane of subeietenoe.

Thie study did not oover Ikidding with horlel, and one ehould be made to bring that made by Soto in 1971 up to date. At that time attempte were being made to introduoe horlal into ekidding and no doubt advanoes have been made einoe then. Suoh a etudy oould be made in the neilhbourhood of the oity of Constitution, where horees are used for ekidding.

The following eubjeote are reoommended for further relearoh on drausht oxen: Ikidding in natural foreete over dietanoee of 1 500 m or lIIore; the tractive foroe and energy produoed by oxen; the feed requirements of tha .. draUSht animals.

- 71 -

Appendix 1

A. CLASSIFICATION OF TYPES OF CHILEAN NATURAL FOREST

(Donolo, 1981)

Foreat typea

Eaoler6filo

Palma chilena

Roble-hualo

Cipr6s de cordillera

Roble-raul!-coigue

Lenga

Arauoaria

Coigue-rauli-tepa

Siempreverde

Aleroe

CiprAs de las Guaiteoas

Coigue de Magallanes

Predominant .paoiel

Quill~, litre, mait'n, elpino

Palma ohilena, litre, peumo, quillay

Roble, hualo, paumo, lin,ue, olivillo, ave llano

CiprAB de oordillera, quillay, boldo, litre

Roble, raul!, ooigue, laurel, lin,ue, ulmo

Len,a, ooigue, rauli, notro, r&dal

Arauoaria, len,a, ooigue, roble, nirre

Coigue, rauli, tepa, trevo, tineo, canelo

Coigue, ulmo, tepa, luma, oanelo

Aleroe, ooigue de Chil06, fuinque, manio

CiprAs de las Guaitecas, coigue, avellano

Coigus de Magallanes, oanelo, maitAn

B. PRINCIPAL TR~ SPECIES IN AREAS STUDIED

Forest type Oak-Evergreen beaoh ooigue

Common name

Coigue

Laurel

Lingue

Lon,-leaved manio

Olivillo

Roble

Tepa

Ulmo

Forest type Coigue-Raul!-Tepa

Common name

canalo

Coigue

Short-leaved manio

Meli

Olivillo

Raul:[

Tepa

Scientifio name

Nothofagus dornbeyi

Laurelia sempervirene

Peraea lingue

Podooarpus salignua

Aextoxicon punctatum

Nothofagus obliqua

Laurelia philippiana

Eucryphia cordi folia

Soientific name

Drimyl winteri

Nothofagua domb~i

Saxegothaea oonapicua

Amomyrtul meli

Aextoxioon punctatum

Nothofagua alpina

Laurelia philippiana

Family

Fagaceae

Monimiaceae

Lauraceae

Podooarpaoeae

Aextoxioaceae

Fagaceae

Monimiaceae

Eucryphiaceae

Family

Winteraceae

Fagaceae

Podocarpaoeae

Myrtaceae

Aaxtoxioaceae

Fagaceae

Monimiaceae

COlllnon name

Tineo

Travo

Ulmo

- 72 -

Soientifio name

WaiDlllannia trioho.perma

DaayPbyllum diaoanthoidea

Buor,yphia cordifolia

Family

Cunoniaoeae

Compoaitae

Euoryphiaoeae

- 73 -

Appendix 2

FORM USED FOR FIELD DATA COLL~TION IN THE TIME STUDY

Date Page no. Plaoe Finishing time Altitude (metres above sea level Starting time Averllle slope Total working time Equipment used Time-lteeper

Forest apsoies: dimensiona and volumes aotivities per work,cyole

of logs; and reoords of times for the operational

Cyole no.

Foreat speoie.

Maximum diameter

Log Minimum diameter

Dimensions Length (m)

Volume (m3)

Operational aotivities Ti.mes recorded 1. Trip without load

2. Loading

3. Trip with load

4. Unloading

Sub-total ,. Supplement for fatigue

5.1

5.2

6. Personal needs

6.1

6.2

1. Dela.Ya (incidentals)

1.1

7.2 1.3

Sub-total

Total time per work oyole

Comments

- 14 -

Appendix 3

DB'l'BRJ(INING COSTS IN SKIDDING WITH OXBN

HOURLY COST IN SKIDDING WITH OXEN IN RADIATA PINE PLANTATIONS

1.1 Labour ooata

1.1.1 Baaio information

Minimum wlIBe

Sooial lawa (5.5~)

LlIBal holida,ya (5.2~)

SUJId..,. (16.8~) Rain.y da,ya (8.4~)

TrlU18port &110w&llOe (s.7&,() Total (minimum daily):

1.1.2 Hour~ ooat

Hourly coat of driver'a work with 7 hour.' effective work per da.Y

1.2 Hour~ oost of team of oxen

1.2.1 Basio information

Purohase value of ox team

Purchase value of ohain, hooks and ring

Purohase value of yoke, yoking straps and goad

Reaale value of ox team

Value of normal feed (one bundle of fodder) per da,y

Value of supplementary feed (3 kg of balanoed feed) per da,y

Q.!!E

217·80 12.09

11·50 36·19 18·40

..liill 309·13

60 000

4 855 1 000

60 000

130

44

Uaeful life of oxen

Uaeful life of ohain, hooks and riAge

Useful life of yoke, yoking straps and goad

6 yearB

5 YBarB

Effeotive d~a of work per annum

Houra of annual work per team of oxen

1.2.2 Fixed ooats (hourly)

1 YBar

200 da,yB

1 400 hours

Inter.at on inveatment in oxen and acoeaaor" equipment: yoke, yoking atraps, goad, ohain, hoou and rinc 5·64

1 040

18·57

Depreoiation

Normal feed

Medioamenta and veterinar,y aervioes (~ of value of ham of o:un)

Mortality (~ of value of team of oxen)

Total fixed ooata

11 OS, 1 • Chp 86.70 (16 December 1983)

2.14

~ 29.89

!!!Ill 2·512 0.139 0.133

0·424 0.212

Q:.ill 3·565

0·509

692.042

55·998 11 ·534

692.042

0.065 0.016 0.214

0,025

1.2.3 Variable ooata (hour~)

Speoial feed

1.3 Totalooats

- 75 -

Total hour~ ooat for akidding with oxen in radiata pine plantationa

6.29

80.34 --.. _-2. HOURLY COST OF SKIDDING WITH OXEN IN NATURAL FORISTS

2.1 Coat of labour

2.1.1 ~io information

Month~ wag .. of driver

2.1.2 Hourly 008t

Hour~ 008t of 124 hour8 of work per month (6 hours a day from Monday to Frida.y and 3 hour8 on Saturday)

2.2 HourlY oost of team of oxen

2.2.1 Basio information

Purohase value of team of oxen

Purohaae value of chain, hooks, ring and orank

Purohase value of yoke, yoking straps and goad

Res.le value of taam of oxen

Useful life of yoke, yokine s traps and Boad

Useful life of oxen

Uaeful life of ohain, hooks, ring and o lamp

Effeotive time of working per annum covering 7 Montha of skidding

2.2.2 Fixed ooate (hour~)

Intere8t on investment in oxen and

1680

61.94

60 000

6.952

1 000

60 000 1 year

6 yeare

5 years

868 hour8

acoe8sory equipment, yoke, yoking strapa, Boad, ohain, hooks, ring and olamp 9.39

2,15 Depreoiation

Medioaments and veterinary servioee ( "'J1, of value of team of oxen)

Mortality ('J1, of value of team of oxen)

Total fixed 008ts

2.2.3 Variable 008ts

Th .. e were not included in the etu4T

2.3 Total 008t8

2.14

~ 16·42

88.581

0.714

692.042

80.184

11·534 692.042

0.108

0.032

0.02;

0.025

0.190

Total hour~ ooet of skidding with oxen in natural for .. t. 11 .1~.:M .~.:m

"'il~T"'o-t"'a"'l"""'ho-ur""'~- ooet in natural for .. t do .. not take into acoount expeneli ture on normal feed and 8Peoial feed.

- 76 -

A. SKIDDING WITH HORSJ:S

The exietin« literature on ekiddin« with horaee in Chile inoludee atudie. made by Soto (1970) 1/, on ekiddin« aawlO£e and pulpwood on various gradienta, with four type. of equipment. The purpoae of the reaaaroh was to ahow how hora .. oould be used in login« radiata pine, and thus make the use of theae animal a more wideapread. The prinoipal oon­atrainta whioh became apparent were trainin« of the animala (whioh varied from one to eight months) and the limited experienoe of the ataff employed.

Draucht horaea have the peculiarity of working beat alone, whereas oxen akid in paira or teame. Beoause of thie, their morphologioal oharacteristios and tractive power, whioh in oxen ia exeroiaed from the head and ths neok and in horaea from the ahoulder, the har­neaa used ia different (aee Fig. 27).

Heed-piece Girth

Bit

Breal1 band

,i,. 27 DRAOOH'l' HORSE FOR SKIDDING, WITH HARNESS AND HAULING IQUIPJIEllT

The hauling equipment used in the experialftta by Soto (1910) was: A Foaaigen trail­er (Fig. 30), VBA Illdse (Fig. 31), Domlnlaxen akidding tonga (Fig. 32) and Ikiddin« ohains. The firat three of theae are of Swldiah orilin and, of them all, only the ohain ia at pr8lent used in Chile. The informa~ion on akidding with horaea in thia Itudy there­fore refera only to the use of ohains. A deaoription and Iketche, of thia equipment will be found in Appendix 48.

Data were oollected on experimental skidding with hor,ea on ground with ,lope. of 6-15 peroent and 16-25 peroent, in a 23-year old unmanaged atand of radiata pine, which had been olear-felled. The treea were on average 2~ m high, with an average d.b.h. of 21 0111. Deneity vas 1 500 tr ... /ha and volwae 510 m /hal

Savlols vere 3.30 m long and pulpwood bolta 2.44 m long.

11 A foreatry degree theaia publiahed by the Foreatry Inatitute (1971)

- 77 -

On ~ro~d with gradients of -6 to -15 peraent, the .peed without load Wal 78./ minute, with load 84 ./minute. The speed without load on gradient. of -16 to -25 peroent Wal 57 ./minute, with load, 55 ./minute.

Average unit a and volumea of load in the Ilope oonditions mentioned above are ahown in Table 13.

AVERAGE LOAD IN UNITS AND VOLUME BY D!OREES OF GRADIENT IN SKIDDING SAWLOGS AND PULPWOOD WITH HORSES

Clus of logl

Sawlogs

Sawloga

Pulpwood

Pulpwood

Degree of gradient

loaded trip (%)

-<i to -15

-16 to -25

-fi to -15

"16 to -25

Avera&e load Avera&e load (unita) (m3)

1.8 0.229

2.2 0.288

16.6 0.376

18.2 0.428

A graph of time and output values obtained by Soto (1970), may be aean in Fig •• 2~ and 29, and the equations in Table 14.

~or-----------------------------------------,

40

20

15

10

1- Pulpwood (- lI'tO - Z5.". I

2- Pulpwood (- 6 to- IS .".,

3-SawloQS (-16to-2S"'"

4- 50wlO91

o 20 40 eo 10 100 120 140 110 110 200 220 240 SkiddinQ disfance in mefre.

Pi,. 28 TIlE 1M IINIlTI!lS PER .J IN SKIDDING SAWLOGS AND PULPWOOD WITH HORSE 01 SLOPIIG GlOUlm

The time per .3 was ahorter on ,entler slop.a. For the fir.t 60 m the time taken to akid sawlog. was le.a than for pulpwood but from this diatance on it inoreased.

-78 -

• ~~

, - Pulpwood ( • 'I to - ZII "Vo ,

2 - PulpwoOd I - • to- 18 "Vo I

S II· Sowlo!!. I - '6 to,- lIS "Vo I

~\\ 4 - Sowl09' I - 6 to- 15 "Vo I

'\ l\ 4

.~~ " . .....

'. ~~ '. S

'~~. , '. ".

""" ~~: .. : .. ::: ... 2 -......; ~ ~::::.,,: .... F=::::::::::, ..... ""

.... I

<i> o 20 40 eo eo 100 120 140 leo 180 200 220 240

SkiddinG di.tonc. In ",.t,"

F1tr. 29 OUTPUT IN' .3/h III SKIDDING SAWLOGS AND PULPWOOD WITH RORSIS ON SLOPING GROUND

Tabla 14

TID EQUATIONS PER rJ AND OUTPUT IN .3/h IN SlCIDDJNG SAWLOGS AND PULPWOOD WITH HORSES ON SLOPING GROUND, USING CHAINS 11

Cl .. _ of De£ree of loS_ _lope for

loaded trip (~)

Sa"lO£_ - 6 to - 15

8&,,10£_ - 16 to - 25

Pulpwood - ~ to - 15

Pulpwood - 16 to - 25

1/ Souro.: Boto B.pdlveda, D10ni.10

., • t1 •• per .3 1n o.nti.inut .. o • output 1n .3/h x • 41.t&l1O. 1n •• tree

T •

T.

T.

T.

Time equat10n Output equation

820.91 + 13.61 ~ o. 6000

820.91 + 13~61J

951.39 + 13,51 Jt 0-6000

951 .39 + 1 3.51 J

1109·04 + 9.97 Jt o -6000

1109.~4 + 9.91 J

1341.12+ 9~11 x o. 6000

1341.12 + 9.11 J

- 79 -

Appendix 4

B. EQUIPMENT USED IN SKIDDING WITH HORSES

POllingen trailer

Thi. oonai.tl of .etalthil. whioh are joined by a ewingletree to the draw bar, whioh oontrol. the steering, and an arrangement of br&kee for the front wheele (eee Fig. 30).

Fig. 30 Foe.ingen trailer (Sweden) 11

The trailer proper oonaiete of a front and rear ..... bly joined together bf a tubular Ihatt, adjuatable for different log lengtha, thua allowing both .. sembli .. to awing freely. Thi. givea the trailer stability. There are alao four metal atakel on the trailer oh .. lia, each of whioh ia made up of two parta .0 that they oan be lengthened or Ihortaned to faoilitate loading from the side.

The teohnioal ap80ifioatione are: tlre., 6.00 x 9: 62 om high; 1.30 m wide, 175 kg in weight; and a oapaoity of 2.5 to 3 tone.

VB! dedee

This oonaiat. of a metal axle under whioh two runner. are fixed in the form of U-ehaped joi.tl. The runner. have lateral and vertioal artioulation (aee Fig. 31).

11 Souroe: Inatituto Porlltal de Chile

- 80 -

Fig. 31 VSA (Varmalanda SkogaarbetBatudier) aledge (Sweden) 1/

The teohnioal oharacteriatioa of the aledge are: 38 om high; olearanoe of 30 em above the ground; 90 om between the runnera; 18 kg total weight.

Domanaaxen akiddi!ll to!lla

Theae oonsiat of two mandiblea, each one with a round oiroular ateel guard 16 mm in diameter, to which the teeth are fi%ed.

The tonga alao have a ohaln 5/16 of an inoh thiok, whioh pas.e. through a tube, where the two mandible. meet, and through a ring in one of theae (aee Fig. 32).

Pig. 32 Do.anaaxen akidding tonga (Sweden)

The maximum opening of the tonga ia 60 om, with an appro%imate weight of 9.8 kg. The deaign ia aui table for akidding larie-d.iameter losa.

-11 Souroes Instituto Foreatal d. Chil.

Ski

ddin

g d

i e"l

lUlO

e (.,

App

endi

x 5

Tab

le 1

5

TIl

lE V

ALU

ES

PER

W

ORK

CY

CL

E,

PER

m

3;

AN

D

OU

TPU

T A

CC

OR

DIN

G

TO

DIS

TAN

CB

A

ND

SLO

PE Il

f SK

IDD

ING

SA

WLO

OS

WIT

H

OX

EN

IN R

AD

IATA

P

INE

PLA

NTA

TIO

NS

Ti.

e' .

per

cy

ah

11

Tim

e p

er .

3 .1

1 S

lope

of

the

grou

nd (~

) S

lope

of

the

grou

nd (

C)

Ou"

lpu"

l (.

3/h

ou

r)

Slo

pe o

f th

e «r

Oun

d (C

)

-25

,1-3

0

-20

,1-2

5

-15-

20

+10+

20

-25

,1-3

0

-20

,1-2

5

-15-

20

+10+

20

-25

,1-3

0

-20

,1-2

5

-15-

20

15

6.8

9

6.5

3

10.0

0 2.

21

8.6

8

9.61

13

.93

5.73

6.

91

6.94

4~31

20

1.2

1

6.92

10

.28

2.11

9.

16

10.1

9 14

.32

1.1

8

6.55

5.

99

4.1

9

30

8.0

3

1.1

0

10.8

4 3,

88

10.1

1 11

.34

15.1

0 10

.01

5.93

5.

29

3,91

40

8.1

9

8.48

11

.40

5.00

11

.01

12.5

0 15

.88

12.9

1 5.

42

4.80

3.

17

50

9.54

9.

21

11.9

6 6.

12

12.0

1 13

.65

16.6

6 15

.86

4,9

9

4.4

0

3.60

60

10.3

0 10

.05

12.5

2 1

.23

12

.91

14.8

3 17

.44

18.1

5 4

,63

4.

06

3.44

10

11.0

6 10

,84

13.0

8 8.

35

13·9

2 15

.96

18.2

2 21

.62

4.31

3,

16

3.29

80

11.8

1 11

.62

13.6

5 9.

41

14.8

1 17

.11

19.0

0 24

.54

4.0

3

3,51

3.

16

90

12.5

1 12

.40

14~20

15.8

3 18

.23

19.1

9 3.

19

3.28

3.

03

100

13·3

3 13

·19

14·1

1 16

·18

19·4

2 20

.51

3.51

3

.09

2.

91

110

14·0

8 13

·91

15·3

3 11

·14

20·5

1 21

.35

3.38

2.

92

2.81

120

14·8

4 14

·15

15·8

9 18

.69

21·1

3 22

.13

3.21

2.

16

2~11

130

15·6

0 15

·53

16·4

5 19~64

22·8

8 22

·91

3·05

2.

62

2.61

140

16·3

5 16

.32

Y

17·0

1 Y

20

·59

24·0

4 Y

23

.69

g,.

2·91

2

·50

Y

2.5

3 Y

150

11·1

1 17

.11

Y

11'5

1 Y

21

·55

25·1

9 Y

24

·41 ~

2·18

2

·38

Y

2·4

5 Y

16

0 11

·81

11.8

9 Y

18

.13

Y

22'5

0 26

· 35

Y

25

·t5

g,.

2.61

2.

21 Y

2

·38

Y

_._

.. _-

11 T

ime

in m

inut

es

y B

%tr

apo1

ated

val

ues

Ave

race

ski

ddin

g lo

ad:

-25.

1 to

-~, 0

.19

4.3

; -2

0.1

to -

25';(

, 0.

679

m3;

-15

to

-20

0.',

0.11

8 m3

; +1

0 to

+~, 0

.386

.3

.

.. I I

+10+

20

10.4

7 8

.}6

5,95

4

,63

3.

18

3.20

0

0

2,17

2,

44

Tab

le

16

00

S'l

' P

ER

.3

AC

CO

RD

ING

T

O

DIS

TA

NC

E

AN

D

SL

OP

E

IN S

KID

DIN

G

SAW

LOG

S W

ITH

O

XEN

IN

RA

DIA

TA

P

INE

PL

AN

TA

TIO

NS

Sk

idd

ins

Ooa

t in

Ohp

an

d i

n U

S, 11

d

iata

uce

-2

5.1

to

-3O

'f,

-20

.1

to -2~

-15

to

-2~

+10

to

+

2fY1

, (.

) I

Chp

US

, O

hp

US,

Chp

US

, C

hp

US,

15

11 .

627

0.1

34

1

2.8

58

0

.14

8

18

.64

6

0.2

15

7

.67

1

0.0

88

20

1

2.2

65

0

.14

2

13

.64

1

0.1

57

1

9.1

69

0

.22

1

9.6

08

0

.11

1

30

13

.54

1

0.1

56

1

5.1

87

0

.17

5

20

.21

5

0.2

33

1

3.4

84

0

.15

5

40

1

4.8

17

0

.17

1

16

.73

3

0.1

93

21

.261

0

.24

5

17

.35

9

0.2

00

50

16

.09

3

0.1

86

1

8.2

79

0

.21

1

22

·30

7

0.2

57

2

1.2

34

0

.24

5

60

17

.36

9

0.2

00

1

9.8

25

0

.22

9

23

.35

3

0.2

69

2

5.1

09

0

,29

0

70

18

.64

5

0.2

15

21

.37

1 0

.24

6

24

.39

9

0.2

81

28

.984

-0

·33

4

80

19

.92

1

0.2

30

2

2.9

17

0

.26

4

25

.44

5

0.2

93

3

2.8

59

0

.37

9

90

21 .

1!?7

0

.24

4

24

·49

4

0.2

82

26

.491

0

.30

6

100

22

.47

3

0.2

59

2

6.0

09

0

.30

0

27

.53

7

0.3

18

11

0 2

3.7

49

0

.27

4

27

.55

5

0.3

18

2

8.5

83

0

·33

0

120

25

.02

5

0.2

89

2

9.1

01

0

.33

6

29

·62

9

0·3

42

1

30

26

.301

0

.30

3

30

.64

7

0.3

53

3

0.6

75

0

·35

4

140

27

.57

7

0.3

18

3

2.1

93

Y

0.3

71

~

31 ·

721

Y

0·3

66

Y

150

28

.85

3

0.3

33

3

3.7

39

Y

0.3

89

~

32.7

67 Y

0

·37

8 Y

16

0 3

0.1

29

0

.34

7

35

.28

5 Y

0

.40

7 ~

33

·81

3 Y

0

·39

0 Y

11

us. 1

-C

hp 8

6.7

0

(16

Dec

embe

r 19

83)

Y B

nra

po

late

d v

alu

es

Av

erag

e S

kid

din

g l

oad

: -2

5.1

to

-3O

'f" 0

794

.3;

-20

.1

to -2~, 0

.67

9.3

; -1

5 t

o -

2fY1

" 0

.71

8 .

3;

+10

to

+2f

Y1"

0.3

86

.3

.

CD

'"

, ,

Slt

idd

ill8

Di.

hacB

Tab

le 1

7

TIl

lE V

ALU

ES

PER

WOR

K C

YC

LE,

PER

m

3;

AND

OU

TPU

T A

CCO

RDIN

G

TO

DIS

TAN

CE

AND

SLO

PE

III

SKID

DII

IG

PULP

WO

OD

WIT

H

OXEN

IN

RA

DIA

TA

PIN

E

PLA

RTA

TIO

RS

Tim

e p

er

cy

cle

1/

Tim

e p

er

m3

1/

Out

pu

t ( .

. 3 /h

) --

(.)

Slo

pe

of

the g

rou

nd

(~)

Slo

pe

of

the g

rou

nd

(~)

Slo

pe

of

the g

rou

nd

(~

)

>-3

0

15

4.21

20

4·

57

30

5·29

40

6.

01

50

6.72

60

7.

44

70

8.16

80

8.

88

90

9.60

10

0 10

.32

Y

110

11.0

3 Y

12

0 11

.75

Y

1/ '1

'i •• i

n m

inu

tes

Y B

xir

ap

ola

t.d

valu

.. -

10.1

-

20

3.97

4.

32

5.00

5.

69

6.38

7.

06

7.75

8.

44

9·13

9.

81 Y

10

·50

Y

11.1

9 Y

Ava

rase

sk

idd

ing

lo

ad:

0.5

09

.3

o -

10

3·52

3.

86

4.')3

').

20

5.88

6.

5')

7.2

2 Y

7.

89 Y

8.

56 Y

9.

24 Y

9.

91 Y

10

.!jB

Y

~-30

-10

,1

-20

o

-10

>

-30

-

10,1

-

20

o -

10

7.06

6·

66

59

0

8.49

9.

00

10~ 1

5 7

67

7.24

6

47

7·83

8.

29

9.27

8

67

8.39

7

60

6·76

7.

15

7,89

10

08

9.')5

8

73

5·

95

6.28

6.

87

11

28

10.6

9 9,

86

5.)2

5.

61

6.09

12

49

11.8

5 10

99

4.80

5.

06

5.46

13

69

13·0

1 12

11

4.

38

4.61

4

.95

Y

14 ~

14·1

6 13

24

4.03

4.

24

4.5

3 Y

16

10

15·3

1 14

37

3.

73

3·92

4

.18

Y

17 3

0 16

,.46

13 2

4 3.

47 Y

3.

64 Y

3.

87 Y

18

51

17,.6

2 16

63

3.24

Y

3.41

Y

3.

61 Y

19

,72

18.7

7 17

76

3,.0

4 Y

3.

20 Y

3.

38 Y

CD ...

SkiddiDl

die'tanoe

Table 18

COSTS PER .3 ACCORDING TO DISTANCE INn SLOPE IN SKIDDING PULPWOOD

WITH OXEN IN RADIATA PINE PLANTATIONS

Cosh in Chp and in US, 11

(-) > - )(If. - 10.1 - 2CJ1, o - 1~ Chp US,

15 9.460 0.109

20 10.267 0.118

30 11 .881 0.137

40 13·500 0.156

50 15.109 0.174

60 16~723 0.193

70 18.)37 0.211

80 19.951 0.230

90 21.565 0.249

100 2),179 Y 0.267 Y 110 24.793 Y 0,~86 Y 120 26.407 Y 0.305 Y

11 US, 1 • Chp 86.70 (16 December 1983)

y ~rapola~ed values

Average skidding load: 0.509 m3

Chp US, Chp ,

8.923 0.103 7·913

9~695 0.112 8~669

11.239 0.130 10.180

12.783 0.147 11 .691

14.327 0.165 13.202

15.871 0.183 14.713

17 .415 0.201 16.224 Y 18.959 0.219 17.735 Y 20.503 0.236 19.247 Y 22.047 Y 0,254 Y 20.756 Y 23.591 Y 0.272 Y 22.268 Y 25.135 Y 0.290 Y 23.779 Y

US, 0.091

0.100

0.117

0~135

0.152

0.170

0.187 Y 0.205 Y 0.222 Y 0~239 Y 0.257 Y 0.274 Y

I

i

I

!

i

I

(XI

l:-

I

Sk

idd

iag

di.t&

lU)8

(.)

15

20

30

40

50

60

70

Tab

le 1

9

TIn

: V

ALU

ES

PER

WOR

K C

TO

LI,

PE

R

1li3

; AN

D O

UTP

UT

ACC

ORD

ING

TO

D

ISTA

NC

E IN

SK

IDD

ING

SAW

LOG

S AN

D PU

LPW

OO

D W

ITH

OX

EN'

ON

LEV

EL

GR

Om

rn

IN

RAD

IATA

PI

NE

PL

AN

TATI

ON

S

Ti.

e p

er o

yo

le 1

1 T

ime

per

m3

11

Out

Pll

t (.

3/h)

Cle

ar-f

elli

ll8

T

hinn

ill8

C

lear-

fell

ill8

T

hinn

i1'll

C

lear

-fel

H1

'II

Sa_

P

ulp

-P

ulp

-S

aw-

Pu

lp-

Pu

lp-

Saw

-P

ulp

-lo

p

woo

d w

ood

log

s w

ood

woo

d lC

CB

woo

d

2.11

2.

93

3.39

5.

05

7.71

11

.74

11.8

8 7·

78

2.45

3,

')3

3.59

5.

87

8.25

12

.41

10.2

2 7.

27

3·13

3.

42

3.97

7.

50

9.33

13

.74

7·99

6·

43

3.81

3.

82

4.36

9·

14

10.4

0 15

·07

6·56

5·

77

4.49

4.

21

4·74

10

.76

11.4

8 16

·40

5·57

5·

23

5·18

4·

61

5·12

12

·41

12·5

5 17

·74

4·83

4·

78

5·86

5·

00

5·51

14~05

13·6

3 19

·07

4·27

4·

40

_~_

1_

-~

---

11 T

iae

in m

inut

ee

bery

e B

kidd

ing

load

: a)

B

swlo

g8 a

fhr

ole

ar-

fell

ing

'"

0.41

7 m

3;

b)

PIllp

woo

d afh

r o

lear-

fell

ing

c

0.36

7 .3

; 0)

PI

llpw

ood

afh

r th

inn

ing

= 0.

289

m3 •

Thi

nni1

'll

Pu

lp-

woo

d

5.11

4.

83

4.37

3.

98

3.66

3.

38

3.14

C

D ""

Sk

icld

illl

Dtn

aaoe

(II'

15

20

30

40

50

60

10 -------

-

Tab

le 2

0

CaJ

'!' P

El

.3 A

CCOR

DDIO

'J'O

DIS

'I'd

:E I

JI S

lCII

IDII

O S

AWLO

OS

AlID

PUL

PWOO

D

WIT

H O

XBrl

om L

Im G

ROUW

D IN

RA

DIA

TA P

INE

PLA

NTA

TIO

NS

CO

Bia

in

Chp

and

US,

11

Cle

ar-

fell

ing

T

hinn

ing

SU

flo

p

Pulp

woo

d Pu

lpw

ood

Chp

US

, C

hp

USI

C

liP

6.16

2 0.

018

10.3

29

0.11

9 15

·122

1.85

1 0.

091

11.0

49

0.12

1 16

.614

10,0

48

0.11

6 12

.489

0.

144

18.3

98

12~239

0.14

1 13

·929

0.

161

20.1

82

14~4

30

0.16

6 15

.369

0·

111

21·9

66

16~6

21

0.19

2 16

.809

0.

194

23·1

50

18.8

12

0.21

1 18

.249

0.

210

25·5

34

11 U

S, 1

-C

hp 8

6.1

0 (

16 D

ec_

ber

198

3)

USI

0.18

1

0.19

2

0.21

2

0.2

33

0.2

53

0.2

14

0.2

94

Av

er.

e B

kid

diy

lo

ad:

a) a

avlo

gB a

fier

ole

ar-

fell

ing

= 0

.411

113

j b)

pu

lpw

ood

afi

er

ole

ar-

fell

ing

~ 0

.361

.3

j

0)

pulp

woo

d afi

er

ihin

nin

g =

0.2

89

.. 3

.

00

'"

Sk

idd

ing

dis

tan

ce

(.)

40

60

80

10

0

12

0

14

0

16

0

18

0

20

0

22

0

24

0

26

0

28

0

300

32

0

34

0

36

0

380

40

0

42

0

44

0

46

0

Tab

le

21

TIl

lE V

AL

tRS

PER

W

ORK

CY

CLE

A

BD

PER

m>

; O

UT

PllT

; A

BD

CO

ST

PER

m3

A

CC

OR

DIN

G

TO

DIS

TA

NC

E

ON

SL

OPE

S O

F -2

0 ~o

-32

PE

RC

EN

T,

FOR

SK

IDD

ING

W

ITH

O

XEN

IN

N

ATU

RA

L FO

RE

ST

Tim

e p

er

Tim

e p

er

m3

Outpu~

oy

cle

!l

111

3 /h

11

16

.51

1

3.9

1

4 ·3

1

17

.53

1

4,7

7

4.0

6

18

.57

1

5.6

4

3.8

4

19

·59

1

6.5

1

3.6

4

20

,61

1

7 .

37

3

.46

21

.64

1

8.2

3

3.2

9

22

.67

1

9·1

0

3.1

4

23

.70

1

9 ·9

6 3

.01

24

.72

2

0..

83

2

.88

25

.75

2

1.6

9

2.7

7

26

.77

2

2·5

6

2.6

6

27

.• 8

0

23

'42

2

.56

28

.83

2

4 ·2

8

2 -4

7

29

·85

2

5·1

5

2·3

9

30

.88

2

6.0

1

2.1

1

31 ·

90

2

6.8

8

2.2

3

32

·93

2

7 ·

74

2

.16

33

·96

28

.61

2

.10

34

.98

2

9·4

7

2.0

4

36

.• 01

30

.34

1

·98

37

.·0

3

31 .

:20

1·9

2

38

.06

3

2.0

6

1.8

7

11 T

ime

in

min

ute

s A

ver

age

skid

din

g l

oad

: 1

.18

7

m3

y U

SI

1 ~

Ch

p 8

6.7

0

(16

D

ecem

ber

1

98

3)

Cos~

per

.3

Ch

p

18

·16

7

19·~95

20

,42

3

21

·55

1

21 .

67

9

23

·80

7

24

·93

5

26

.06

3

27

·19

1

28

·31

9

29

·44

2

30

.57

2

31 .

70

3

32

.83

1

33

·3

60

3

5.0

87

36

.• 2

15

37

.34

3

38

·47

1

39

·39

9

40

·72

7

41

·85

5

US,

0.2

10

0.2

22

0.2

35

0.2

49

0

.26

2

0.2

75

0.2

88

0.·3

01

0·3

14

0·3

27

0·3

40

0·3

53

0.3

66

0-)

87

0·3

92

0

.40

5

0.4

18

0·4

31

0'4

44

0'4

57

0·4

70

0

·48

3

00

....

Tab

le 2

2

TID

VAL

UES

PER

WOR

K CY

CLE

AND

PER

m ';

O

UTP

UT;

AN

D CO

ST

PER

.3

In S

KID

DIN

G W

ITH

AN

AG

RICU

LTU

RAL

TRAC

TOR

ON S

LOPE

S OF

+

0.1

5 T

O +

9.38

PER

CEN

T

Sk

idd

ing

T

ime

per

dis

tan

ce

oy

ole

(II)

1.1

20

5.6

0

25

5.6

7

30

5·7

4

35

5·81

40

5.8

8

45

5·9

5

50

6.0

2

55

6.0

9

60

6.1

6

65

6.2

3

70

6.3

0

~~-

_ ..

_-

1.1 T

ille

in

m

inu

tes

Y U

SI 1

•

Chp

86

.70

(16

D

eoem

ber

1983

)

Ave

rage

sk

idd

ing

lo

ad:

0.8

65

.3

Tim

e p

er .

3

Out

put

1.1

m3/

h C

hp

6.4

7

9.2

7

70

.97

0

6.5

5

9.1

5

71 .1

362

6.6

3

9.0

4

72·'7

55

6.71

8

.93

73

-'547

6.8

0

8.8

3

74

·54

0

6.8

8

8·7

2

75

·43

2

6.9

6

8.6

2

76

·32

5

7.0

4

8.5

2

77 .2

17

7.1

2

8.4

2

78

.11

0

7.2

0

8.3

3

79,'J

02

7.2

8

8.2

3

79

.99

5

----

--~-

----

Cos

t p

er m

3

USI

Y

0.81

7

0.8

29

0.8

39

0·8

49

o. !l

60

0.8

70

0.8

80

0.89

1

0.90

1

0.91

1

0.92

1

I

<lD

ex>

- 89 -

DI'l'BRIIINING COSTS IN SKIDDING WITH AGRICULTURAL TRACTORS

LABOUR COST 11 1.1 Baaio information

Monthly waBes of tractor driver

Monthly waBes of ohokerman

1.2 Hourly co.t

Hourly co.t on the bui. of 156 working hoW'll per month

2 HOURLY COST OF THE TRACTOR

2.1 Baaio information

Purohaae value of the tractor

Final value of the tractor

Purchue value of the winoh

Final value of the winch

Replacement value of front tire.

Replacement value of back tire.

U.eful life of the tractor, in year.

Annual use of the tractor, in hour.

U.eful life of the tire., in hour.

Useful life of the .teel hook, in years

Useful life of the cable for the winch, in month.

2.2 Fixed oosts, per hour

1) Intere.t

b) Depreoiation

0) Lioenoe

'Fotal fixed oosta

,2.3 Variable oost. per hour

a) Repairs

b) Tire.

0) Fuel 2.5 litre./h x Chp 35.90 d) L~brioants, filters and greue

011 for gearbox

6 litree x Chp 220 -1400 h

11 Inolude •• ooi&l seour1 ty

1I usa 1 - Chp 86.70 (16 December 1983)

2!!2 14000 8000

22 000

141.03

ygy 161~47'

92.272

253·748

1.627

577 940 18 200·000 134 000 545.559 60 640 669.423 40000 461·361 20 866 240.669 84 044 969·366

10 1 400 3000

5 2

77.68 0.896 97,.12 1 .120

~ 0.024

176.64 2.040

98.59 1 .137

34.97 0.403 89.75 1.035

0~'J4

- 90 -

Oil for ellBin. 0 ....

11 litr .. x Chp 300 • 120 h 42.50 0·490

Oil for ~draulio ellBine and diff.rential

80 litr .. x Chp 220 •

1400 h 12·51 0.145

Filters for the fuel

2 x Chp 180 •

3x156h 0·11 0.009

Filters for the ~draulio ellBine

2 x Chp 135 •

3x156h 0·58 0·001

e' Hoole and oable

hook to bear 2 tons of traction

Chp 900 .. 0,13 0.001 5 x 1 400 h

Cable of 5/8" for the winoh

l:2 m x Chp llO -2 x 156h 31.02 0.421

f) Maintenanoe

14 000 x 1 • 156 h x 4 22·44 0.259

Total variable oosts 340.26 3·925

3 TOTAL COSTS

Total hour~ oost 658.13 1.591

- 91 -

BIBLIOGRAPHY

AGENJO CECILIA C. Ganado vacuna. Editorial Elpaaa Calpe, Jladrid. 537 p. 1945.

ANAYA LOPEZ, HECTOR. Transporte foreltal oon tractorel, cablel, helioopterol Y ,loboB. FAO/SIDA/lEXICO Seminar on TranBportiJII LOCB in Latin Amerioan Countriea. FAO (93/126), Rome. 1975.

ANAYA LOPEZ, HECTOR & QUEVEDO, V.T. Jletodologia para determinar COBtOB Y rendimientoB en operacioneB de apeo y tranlporte foreBtal. FAO/SIDAjmICO Seminar on TransportiJII LogB in Latin Amerioan Countriel. FAO (127/152). Rome. 1915.

BEZADA, A.A FRISK, T. Eltudio .obre la operaoi6n de tractoreB foreltalea de rued .. en Perd. Project UNDP/FAO/m/78/003, Improvement of SyatemB of "ForeBt lIlxtraotion and TranBformation. FAO WorKiJII Paper No.4, (36/39). Lima, Peru. 1980.

BOOK, T.V. Patologia veterinaria en )00 imageneB. Tranalated into SpaniBh by Manuel Barber&n. Editorial AedoB. Barcelona. 176 p. 1911.

CARDIEL MATEUS, LUIS. Tiempoa y tareaa, oomo medir, oomo oaloular. Editorial Limuaa. Mexioo. 111 p. 1914.

CATERPILLAR TRACTOR CO. Coatol de poaeBion y operaoi6n. Rendimiento de loa produotoa Caterpillar. Fifth edition. (1/40) Mexioo. 1915.

CONAF, INFOR. EltadiBtioas foreBtalea 1982. Serie informatica No. 11. Santiago de Chile. 84 p. 1983.

CONAF, INFOR. Exportaoione. foreataleB ohilenaa. Serie informatioa No. 12. Santiago de Chile. 84 p. 1983.

CONAF, INFOR. La industria del .. arrio durante 1982. Santiago de Chile. 13 p. 1983.

CORDOVA, NILO & FRISK, TORSTEN. EBtudio de rendimiento potenoial y extraooi6n foreatal Bn el bOBque naoional Alexander von Humboldt. Projeot UNDP/FAO/PER/18/003, Improvement of SYBtemB of Foreat Extraotion and Transformation. FAO WorKing Paper No.1. FAO. Lima, Peru. 28 p. 1919.

CHILE/OAS/IBD. SueloB. Proyeoto aerofotogrametrioo. Publicaoion No.2. Inltituto de InveBtigaoion de RecurloB Naturalea (IREN), CORFO. Santiago de Chile. 391 p. 1964.

DE LA MAZA, T., ELVIRA M.L.E. & GARCIA F.M. El empleo de la traooi6n animal en 101 aproveohamientol foreataleB. Miniaterio de Agricultura. Inatituto Foreatal de Inveatigaoionea y Experieneias. Madrid. 195 p. 1961.

DONOSO ZEGERS, CLAUD[O. Tipoa foreatalea de loa bel que. nativol de Chile. FAO Working Paper No. 38. FO:DP/CHI/16/003. FAO/UNDP/CONAF Reaearoh project. Santi~o de Chile. 10 p. 1981

DONOSO ZlGERS, CLAUDIO. Eoologia foreatal y IU medio ambiente. Faculty of Forelt Soianoel, UniverBidad Austral of Chile. Valdivia. 369 p. 1981.

DRUMMOND, R.O. tio~borne liveltook diBeasee and their veotorB. World Animal Review. PAO. No. 19 (28/33). Rome.

~I~AU1oR, G9,O~O. ~Itudio de raoionalizaoi6n de lAB faenaa de volteo y Baoa en una plantaoi6n de pino insigne. Publioaoi6n Cientifioa No. 14. Univerlidad AUltral de ChilB. Valdivia. 31 p. 1969.

ENSMINGER, B.M. Manual del Ganadero. Biblioteoa de produooi6n animal. Danville, IllinoiB. 188 p. 1970.

FAO. Eltudio de tiempoB y produotividad, elaboraoi6n de la madera para la induBtria de la oeluloea y el papel. lnetituto de Ordenaoi6n dl Vertientel e ingenieria Foreetal de Argentina. Report preparBd for the Government of ArBentina Qy FAO. Rome. 23 p. 1910.

FAO. LOlling and log tranaport in tropical high foreBt. Foreltry Development Paper No. 18. Rome. 99 p. 1914.

FAO. Basio teohnolO£1 in foreBt operations. ForeBtry Paper No. 36. Rome. 122 p. 1983.

- 92 -

PRISK, TORSTKN & GUELL, GUILLERMO. ladereo meoanizado oon tractor forestal artioulado. Institu~o Forestal de Chile. Technioal report No. 40. Santiago, Chile. 59 p. 1912.

GaE, R.I. Current status of research on animal traction. World Animal Review No. 45. FAO. (2-11). Rome. 1983.

HERNANDEZ GARCl~S, EIXJAROO. Evaluaoi6n de ooetol por etapal de produooi6n de madera .. errada en una emprela maderera del bosque nativo. Degree thelia. Univeraidad Austral de Chile. Valdivia. 95 p. 1969.

HOPFEN, H.J. Farm implemeniB for arid and tropioal regions. Revised edition. FAO. 154 p. 1910.

INSTITUTO GEOORAFICO MILITAR. Atlas regionalizado de Chile. Seoond edition. Santiago de Chile. 64 p. 1981.

lREN-UACH. Estudio de suelos de la Provinoia de Valdivia. Santiago. 118 p. 1918.

JELVEZ cAAMJIo, WAIUEL. Rendimientos y oostos para diferentes m'todos de raleos de pino insigne, Pinus radiata D. Don. Degree theais. Universidad de Chile. Valdivia. 59 p. 1911. -- --

MAY BULLON, BERNANOO. Plan de manejo ''Fundo Peral .. ". Chile. 56 p. 1919.

MCOONALD, P., EDUARM, R.A., & GREENHALGH, I.F. Nutrioion animal. Translated from English into Spanish by Aurora Perez T. Editorial Acribia. Zaragoza, Spain. 462 p. 1919.

MERY G. JOSE. Como cuidar 101 neumaticol de uso agrIcola. La Hacienda. No.2 (81/88). Santiago. 1981.

MORALES, A.R., OLIVARES, P.B., GUTIERREZ, M.J., & GARCIA, S.J. Estado actual del manejo de plantaciones de ~ Radiata ~ ~ en Chile. Projeot CONAF/UNDPjFAO-CHI-16-o03-2/F0. Report No.1. Chile. 80 p.

MORROW LEB, ROBERT. Eatudio de tiempos y eoonomia de movimientos. Ediciones Contabili­dad loderna. Buenos Aires. 429 p. 1957.

NAVAJAS FUENTES, JOSE. Castraci6n de animales domestioos en el medio rural. No mention editorial. Madrid. 110 p. 1955.

ILO. Introduooi6n al estudio del trabajo. aeneva. 365 p. 1970.

OVERGAARD,JORCEN. Derivaci6n de la formula de oostos de maquinas. FAO/SIDA/MEXICO Seminar on Transporting Logs in Latin Amerio~ Countries. FAO. (85-92). Rome. 1915.

PAREDIS V.G., MORALES V.~., & DONOSO, Z.C. Antecedentes sobre el seotor forestal de Chile. Univerlidad Austral de Chile. Valdivia. 48 p. 1981.

PUGIN JARA, CARLOS R. Factibilidad tecnioa y econ6mioa sobre la establioizaci6n de sue loa finos oon emullionea asfaltioas y su aplioaci6n en oonstruccion de oaminos forestalea. D~ee thelis. Faculty of Forestry of the Universidad Austral de Chile. Valdivia. 55 p. 1981.

SEARS, FRANCIS. & ZAMANSKY, MARK. Fiaioa general. Cuarta edioi6n. Editorial Aguilar. Madrid. 1 040 p. 1963.

SMITH, A.J. Draught animal reaearoh - a neglected subject. World Animal Review No. 40 (43-48). FAO. Rome. 1981.

SOTO, DIONISIO. Estudio de madereo oon oaballos. Degree thesis. Faculty of Forelt Soienoes of the Univeraidad de Chile. Santiago, Chile. 116 p. 1910.

SOTO, DIONISIO. Estudio de madereo oon oaballos. Instituto Foreltal de Chile. Technioal Report No. 39. Santiago, Chile. 54 p. 1911.

STARKEY, P.R. N'DaIIIa oattle &I dra\llht animala in Sierra Leone. World Animal Review No. 42. (19/42). FAO. Ra.e. 1982.

TORRIS OJEDA, HERNAN. laderae. Corporaci6n ohilena de la madera. Santiago, Chile 210 p. 1911. WBBER, WALFRIED. Silnoultura Chilena actual. Universidad Austral de Chile. Valdivia. 13 p. 1951. WOOliDRIIXJE, R.W. Wermedades de los animales dOllesUoos. Alimentaci6n e higiene. Firat edition in Spanish. Editorial Continental. lexioo. D.F. 562 p.