Rangeland Management - user 657/Rangeland Manage… · Rangeland Management GEOG/ENVS 657 Dr. B.A....

1

Rangeland Management

GEOG/ENVS 657Dr. B.A. Holzman

Rangeland Management• Definition of terms• Rangeland goods & services• History of RM• Laws pertaining to RM• Rangeland Ecology• Measure in RM• Grazing systems• Multiple Use• Wildlife and Range

Rangeland

• Land supporting native vegetation that is either grazed or has the potential to be grazed and managed as a natural ecosystem: includes grassland, grazeable forest, shrubland, pastureland

• Pastureland: Cultivated for (nonnative) forage- involves agricultural practices

GEOG/ENVS 657NATURAL RESOURCE MANAGMENT

DR. B.A. HOLZMANSFSU

FOR THE EXCLUSIVE USE OF STUDENTS ENROLLED IN GEOG/ENVS 657

2

• Nearly 80% of the lands of the West are classified as rangelands whereas only 7% of some areas near the East Coast are classified as rangelands.




3

______________________ * % of their total areas in drylands ** The term rangelands, for purposes of desertification assessment, includes all territories presently used as grazing lands, which are accounted for in yearly FAOs statistics, as well as other non-agricultural, largely unoccupied, drylands which are used only occasionally by nomadic pastoralists or are presently unused at all.

1004409 30926 70 3475 Total

100131 70 91 30 40 Irrigated lands

100 570 40 235 60 335 Rainfed croplands

100 370020600 80 3100Rangelands**

%*

million hectares

%*million hectares%*

million hectares

TOTAL

NOT AFFECTED BY DESERTI-FICATION

AFFECTED BYDESERTI-FICATION


• Management or manipulation of rangeland components to obtain optimum combination of goods and services for society on a sustained basis

Can be taught as agricultural or ecological profession

(rangeland ecologist/ rangeland manager)




4

• Herbivory: The consumption of plants by animals.

• Grazing: The consumption of standing forage (edible grassesand forbs) by livestock or wildlife.

• Browsing: Consumption of edible leavers and twigs from woody plants (trees and shrubs) by large hoofed animals.


Two components1) protecting and enhancing soil and

vegetation complex.

2) maintaining/improving output of consumable range products (meat, fiber, wood, water, and wildlife)

Concepts of RM• Rangeland is renewable• Energy from the sun fuels the system• Rangelands supply humans with food and fiber

(cost less than pasture)• Productivity (amount of available forage) is

determined by characteristics of soil topography, and climate

• Variety of products can be produced (food, fiber, wildlife, minerals, and timber) and harvested from rangelands




5

Rangeland management needs to rely on information from many fields: biology, geology, soils, chemistry, nutrition, economics, agriculture, recreation and ecology.

What goods and services are derived from rangelands?

• a habitat for animal species; • a habitat for native plant species; • a source of high quality water, clean air

and open spaces; • a setting for recreation• the foundation for low-input, fully

renewable food and fiber production

• Native grazing• 1515 -1540: Livestock introduced in

Mexico and escapees end in Texas• 1590: Sheep grazing established in New

Mexico and Arizona• 17th Century: Spanish settlement

– Missions

History of Rangelands and US




6

• 1849 Gold rush: Animals in California• 1865-1900 Cattle drives from Texas

through the Plains• 1870s increase cattle on the plains/imports

to Europe

1800s

Cattle drives

Late 1800s

• 1880-1890s cattle/sheep rancher conflicts• 1870-1930 “Oh the farmer and the

cowman should be friends”• 1885-86 Severe winter on

the plains,1891-92 severe drought




7

• 1862: Homestead Act (160 ac)

• 1909: Enlarged Homestead Act (320 ac)

• 1916: Stockraising Homestead Act (640 ac)

• Tragedy of the Commons

Late 1800s (cont.)

1900-1930s

• 1898 System for grazing permits on federal land

• 1905 USFS set up in USDA• 1910-1920 Grazing laws put into affect on

fed land• 1920 Range Management as a

discipline

1930-1960s

• 1931-36 Severe drought• 1933-35 Soil Erosion Service (’33)-

Soil Conservation Service (‘35) • 1934 Taylor Grazing Act• 1948: Society for Range Management




8

1960-2000• 1960 MUSY• 1976 FLPMA• 1962-92 Decrease in grazing of Federal

lands

1970s The Sagebrush Rebellion1990 The “Wise Use” Movement

Rangeland and wildlife

• Rangelands comprise about 95% of food source for wild animals

• Compete for forage, water and land




9

Rangeland Measurements

• AUM • Weight/biomass• Area/Cover• Density/frequency• Grazing Capacity

Animal Units/AUM

AU= 1 cow or cow with suckling calf (1000lb)AUM : 26 lbs dry matter (DM) per day as

forage, combined with a factor for tramping and waste of about 25%, results in an estimate of about 1000 pounds of dry matter (DM) from forage to supply one AU each month

AUMs

1.25Full grown horse

0.14White-tail deer

0.2Ewe and lamb

0.2Mule deer




10

Grazing Intensity

• Heavy Use: clipped or mowed appearance, trail evidence, all areas show use

• Moderate Use: about ½ of good/fair forage, value plants used, little trailing evident,most of the range shows some use

• Light Use: choice plants and areas used, no use of poor forage, range lightly disturbed




11

Weight/biomass

• Grazing capacity– Clipped plot – Grazing capacity per unit area∑(dry weight per unit area* species use factor)

for each plant species_______________animal unit requirement




12

Area/cover

Used to evaluate: soil protection, watershed health, rangeland condition and range trendAerial or canopy coverBasal coverMethods: ocular estimation,

step point method, line intercept methodpoint frame

Density/Frequency

Used to determine plant survival, monitor regrowth, look at grazing affects

Density: number of individual plants per area

Frequency: quantitative expression of presence/absence of individuals of a species in a population

Using Exclosures




Rangeland Management - user 657/Rangeland Manage… · Rangeland Management GEOG/ENVS 657 Dr. B.A....

Documents

Transcript of Rangeland Management - user 657/Rangeland Manage… · Rangeland Management GEOG/ENVS 657 Dr. B.A....