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Tales Trees TellStory 1:

The Wisdom of the Ancients

By Harold C. FrittsDendroPower Press

5703 North Lady LaneTucson, Arizona 85704-3905

August 08, 2000Copyright 12/29/1998 by Harold C. Fritts

Photo by Donald Graybill courtesy of GaryFunkhouser


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IntroductionHigh in the arid WhiteMountains of California near theNevada border you can find theoldest trees in the world, theancient, gnarled bristleconepine (Pinus longaeva)1. Theoldest known age of a livebristlecone pine is 4900 years.

Just think of this: a century inthe life of a 4900 year oldbristlecone pine is equivalentto two years for you and me.

These ancient trees grow inharsh dry mountainous terrainin the rain shadow of the SierraNevada. There is littlemoisture in the air; and not farsouth lies Death Valley, thedriest and hottest land in theUnited States. The bristleconepine environment is so extreme

1The first time a common name or measurement is mentioned I will also give the scientificname or measurement enclosed in brackets.

The most ancient bristleconepines are about 20 feet (6

meters) tall yet they are up to4900 years old.

The exposed contorted wood inthis magnificent ancient graduallyweathers to a rich reddish brownhue, yet the tree hangs on to life

through a single living branchshown on the right.


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that the trees can grow only very slowly for a short durationin summer. The annual growth rings, stem diameter andheight are small compared to most trees, but theirremarkable age and the sheer majesty of their spiked tops,twisted, gnarled branches, the rich brown color of theweathered wood and brushy green branches makes up fortheir diminutive size. If you are lucky enough to visit theseancient trees, enjoy their beauty but please don’t takesouvenirs. It is hard enough to survive to such an old agewithout people breaking branches, cutting pieces off thebark or collecting cones. It removes much of their beautyand is illegal too!

How to Find the Real Age of a BristleconePine

How can we measure the age of these trees? Many ofyou already know that treeswill produce one growth ringin their stem for each year;and all one needs to do is tocount their rings! But likemost things in life, the story isnot as simple as that. Let meexplain.

I am a scientist, who workswith trees and their rings in afield called dendrochronology.“Dendro” means tree and“chronology” means time.Dendrochronologists workwith tree time which provides

A tree ring in fast-growingbristlecone pine includes about20 cells that are large with thin

walls when growth begins in lateJune and smaller and thicker

walls when growth slows down inlate July. The rings in the ancienttrees may have 3 to 5 cells and

are much narrower. Photocourtesy of Fritz Schweingruber


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considerably more information than simply the age of thetree. Instead of simply counting, dendrochronologists usea procedure called cross-dating to establish the exact yeareach ring grew from the beginning of the trees life to thetime it was sampled. Then by observing and measuring theyearly changes in ring size, structure and density they canlearn a great deal about the environmental conditions datedto the very year when each ring grew.

The growth rate of bristlecone pine can be so slow in verydry or cold years, that some trees fail to grow so that thering is missing at the base of the trunk where they would

naturally be counted. Ifthe rings had beencounted rather thancross-dated, the treeage would be one yearless for every year thatthe tree did not producea complete ring.

The procedure ofcross-dating matchesthe patterns of wide andnarrow rings in a largenumber of trees. Anarrow ring can befound in faster growingtrees during the sameyear that the ring ismissing in slowergrowing ancients.When the pattern of

Two of my scientist friends. JohnCardis, on the left, helped me studyhow the bristlecone pine grow and

Wes Furguson, on the right,searched for the oldest trees and

developed their long record of pastwet and dry years.


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wide and narrow rings is memorized or recorded in someway, it is easy to identify where in a stem a growth ring ismissing or when mistakes or other types of problems occur.This allows dendrochronologists to identify the chronology(timing) of every ring to the exact year in which it grew. Iwill postpone describing more details of this importantcross-dating procedure until the next Tale “A Day with theGiants” and get on with this story about the ancient ones.

Dendrochronologists can read the story that is lockedin the widths of the cross-dated tree rings. The width tellshow well the tree grew each year. In addition the ring maycontain a particular kind of scar with charcoal that indicatesa fire may have injured the tree in that year. Insectdamage can be revealed by certain changes in ring width,frosts leave their mark by injuring cells, chemicals arestored in the wood; and there are other featuresdendrochronologists can use to read the story from theannual rings.

Of course it isnot necessary tocut down a treeto examine therings. A pencil-thin core can beextracted fromthe main stem ina way thatminimizes thedamage to thetree. The tree

A corer is inserted into the tree stem and a pencil-thin core is extracted which contains the story in

the form of annual rings.


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oozes resin that fills the core hole and in a year or so thewound is completely healed.

A core is then sanded or cutto obtain a clean surfaceshowing the rings. The widthof each ring is measured orthe ring is examined, and thefeature in question isrecorded and analyzed toreveal the story. It is liketranslating a foreignlanguage into English.

Each of the “Tales TreesTell” is a story of howdifferent trees can writedifferent stories, what thedendrochronology detectivesdo to read the story, as wellas, my sharing with you thesheer beauty, joy andpassion one can experiencevisiting and working withthese magnificent beings wecall trees. In addition Ibelieve there is a lot ofwisdom one can gain fromsimply being with trees,especially these ancientones. I will share some ofmy thoughts andexperiences while working

The bristlecone pine have aremarkable adaptation to these rocky,

arid and cool sites. When the treebecomes too large, branches begin to

die, sometimes including the mainstem, because of lack of water on therocky sites. The stems do not rot asthey are preserved by the resin in the

wood. Even with this gradualreduction in living crown, bark androots, the tree remains healthy and

continues to grow in balance with theamount of moisture available between

the cracks of the rocks. The livingmass of the tree remains constant

allowing the trees to attain a very oldtree.


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with trees and their annual growth rings.

The Ancient Trees

How can the bristlecone pines live so long? The easiestanswer might be that God created such a tree to live in theharsh dry and cold environment high in the mountains.From one point of view this may be true. However,scientists want to understand the mechanisms that allowsuch trees to come to be, or be created, if you want to sayit that way. Scientists have offered a number of ideas,called theories or best inferences, as to why these treescan live to such a ripe old age. Some people suggest“adversity breeds longevity” or to say it in simple words:“when things are tough in the world, we can learn to copewith the difficulties.” This learning is called wisdom, whichpeople can use to heal themselves and grow throughouttheir lives. If we become wise enough, we know how to livewell and can become a very old but healthy man or womanlike these ancient trees.

That is certainly one important message the bristleconepines can tell us, but there are lots of old bristlecone pines,not just a few ancients that may have learned suchwisdom. Scientists have another theory which they believehas been proven to be most likely or true. It is called“Evolution”. The following paragraphs describe how theseancient trees could have evolved over a long period of time.The process we call evolution is stated in very simpleterms.

Evolution of the Ancients


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Many, many years ago someancestors of bristlecone pinegrowing in warmer and moremoist places produced offspring(children) who were able to live insomewhat drier and higher sitesthan their parents could. Thisprobably occurred at a time longbefore the ice ages when theclimate in this region was coolingand becoming drier due to thegradual rising of the SierraNevada Mountains. As thesepines produced offspring, somewere like their parents and couldnot cope with the somewhat drierand cooler conditions so theydied before they created new offspring. Some offspringwere produced that could cope very well with theseincreasingly adverse conditions. They lived longer and hadtheir own children that could survive and grow to asomewhat older age. Some of their children were able togrow in even drier and higher places than their grandparents and great grandparents could. The offspring thatcould not cope with the cold and dry conditions neversurvived. This was repeated for many many generationsuntil they evolved into the bristlecone pine of today. Somescientists describe this process as “survival of the fittest”and the slow process of changing as evolution.

These are not ghost trees but aclose relative of our bristlecone

pine in the clouds over Mt.Evans, Colorado Rocky

Mountains.


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Today, the closest relative is the Rocky Mountainbristlecone pine (Pinus aristata) growing in more moisthabitats in the Rocky Mountains of Colorado and NewMexico. Just across the valley from the California WhiteMountains are the high Sierra Nevada where we can findthe next closest relative, the foxtail pine (Pinus balfouriana).The foxtail pine also grow high on the mountain slopes butrequire more moisture and are not as old as the bristleconepine. Long ago these trees probably originated from thesame parents as the bristlecone pine, but this populationbecame separated from the bristlecone pine in the WhiteMountains. When populations are separated and isolatedin this way, each population can evolve in slightly differentdirections because the forces of nature that controlledsuccess or lack of success of offspring were slightlydifferent in each habitat.

The Extreme SitesOccupied by

Bristlecone Pine

On clear winter days one can see the SierraNevada Mountains west of the bristleconepine in the White Mountains. Bristlecone

pine cannot grow there but a relative calledfoxtail pine grows on the highest slopes.


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What must it be like to live in these high, dry, cold androcky mountains that are much higher than most of us areused to. The oldest bristlecone pine grow at the lowestelevations that bristlecone can grow at about 9500 feet(2896m), but bristlecone pine can grow to the upper treeline, about 11000 feet (3353m). The trees at the upper treeline are larger but not as ancient as the trees at the lowerforest border below them.

It is interesting thatthe lowest andhighest bristleconepine not only reachdifferent maximumages, but the widthof the rings telldifferent tales. Tounderstand why, it ishelpful to know thattrees, like all livingthings, require foodand water to live andgrow. Without atleast some waterthey could not livemore than a few days unless they were frozen during thewinter. Without water they would dry up and die ofdrought. If there was no source of new food, the treesmight live for a few years on food stored in their cells, butthey would eventually die of starvation.

The largest bristlecone pine, the Patriarch, isfound near the upper tree line. It’s trunk is

3394 feet (103m) in circumference; the crownspread is 41 feet (12.5m); and it is 47 feet (14m)

tall. It is not as old as some of the smallerstrip-barked trees near the lower forest border.


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You also know that you will not grow as much if you havelittle food and water. If you have enough, but not too much,you might be skinny, but could grow strong and live a longtime if you eat the right kinds of foods. The same is true oftrees. If they have enough food or water, but not too much,they will grow slowly with narrow rings, be stunted, strongand able to become very old. As the young trees grow

older and larger they exhaust thesoil space in which the rootsgrow. Soil moisture becomesmore limiting during times ofdrought. The most exposedbranches dry out and die alongwith the connecting bark andassociated roots. Thosebranches that remain alive arestill connected to living roots bylong strips of bark. What wereonce circular rings becomegrowth layers formed under thestrips of bark.. With the passingof time the main stem of the treeloses its circular shape althoughthe mass of the living treeremains relatively constantthrough time.

Under adversity, parts of theliving bark die, but the tree

remains healthy and new ringsgrow under the remaining

bark. These are called strip-bark trees.


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As long as you have food and water, your body stayswarm. In cooler weather you put on a coat to help keepyour body from losing its heat. Your body uses much ofthe food you eat to keep you warm. Trees cannot makeheat and keep warm, so if they are bristlecone pine, theymust be able to live and survive the low temperatures inwinter. They do use food simply to keep alive whentemperatures are above freezing. Also trees can grow onlywhen temperatures are consistently above the freezing

point.

Trees, like all greenplants, cannot eat food.They make their foodbeginning with sugar, in aprocess calledphotosynthesis, whichrequires carbon dioxide,water, light and the greentissue, calledchlorenchyma, found inleaves, needles andsome stems. All theother foods andstructures are made fromthis sugar with theaddition of minerals andrearrangement of thecarbon, oxygen andhydrogen molecules ofthe sugar.

The green tissue (chlorenchyma) in theneedles carry on photosynthesis in the

presence of light making sugar that is usedto make other foods and cell parts in the

living bristlecone pine. The brownstructures are pollen producing cones.


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Animals and some plants that are not green must gettheir food from plants or other animals that in turn eatplants. Both you and I, along with other animals, musthave plants for the food and energy that our body needs.Trees, like all green plants, also use the carbon dioxidefrom the air to make sugar and release the oxygen that youmust breathe in to live, but that is a more complicated storywhich I will explain in a later tale.

The Lower Forest Border Bristlecone Pine

Let us continue with the stories that the bristlecone pinetell. We will start with the lowest and oldest trees.Because they are living lower on the mountains, the wintersare not as cold and the summers are warmer and drier. Thetrees thaw out sooner with the warmer temperature andbegin making sugar earlier than the trees at higher sites.

As the weather gets warmer, the trees can begin to grow ifthey have enough food and water. The bristlecone pines atthe lower forest border sites also lose water rapidlybecause of warmertemperatures. As theroots absorb water thesoil becomes drier. Ifthere is little moisturein the soil from a lackof winter snow or rain,the tree may becomeso dry that both growthand photosynthesisslow down and evenstop. As we said A typical open stand of bristlecone pine near

the lower forest border. Each tree requires alot of space in order to have enough water to

remain alive and grow.


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before, in extreme drought, growth may never start at thebase of the slowest growing trees.

The trees also have “learned” in the evolution process thatthey should stop growing before it becomes too cold andkilling frosts can occur. The bristlecone pines start growthwhen it is warm enough, grow for about 45 days, and thenthe growth stops even though the weather is still warm.They may continue to make sugar in the presence of light ifwater is still available in the soil and it is not too cold. Thissugar may be used to make pine cones and seeds, or it isstored in the living tissues until growth begins the nextyear. If there is plenty of moisture in the soil from thewinter snow or from spring rains, they make lots of sugar,grow very rapidly and make very wide rings. If there is littlemoisture, with little sugar stored from the previous year,growth is slowand the ringsare not verywide. Thewidth of therings in theancient treesat lowerelevations tellus about wetyears and dryyears for aslong as theyhave grown. Very narrow or absent rings in the slowergrowing trees indicate years of sever drought.

The old trees become twisted and gnarled and whenthey die they leave beautiful brown twisted contortedshapes showing the effects of former drought, wind

and blowing winter snow.


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Even the dead trees inthis ancient forest cantell the same kinds ofstories in their rings.The wood remains firmas it is filled withprotective resins, andunder the dry climatesome of the wood lies onthe ground for thousandsof years. When therings in this wood arecross-dated with oldliving trees,dendrochronologists canextend the record ofdrought well beyond theage of the oldest livingtrees. The record of pastdroughts extends

backward 8700 years,and there are some olderundated fragments thatwill eventually extend thisrecord even further backin time.

People have measuredrainfall and snowfall forlittle more than the last100 years. The ringwidths in these ancient

The wood of dead trees lasts a very longtime in this harsh and dry environment.One can examine the rings in this wood

to extend the tree ring record furtherback in time.

The bristlecone pine at higher elevations arelarger and not as old. Their rings tell a story

about warm and cool years.


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trees can becorrelated with this100 year record andused to extend thissnow and rainfallrecord over 8700years which is anincrease in length ofrecord by 87 times.

The Upper TreeLine

BristleconePine

What about thering widths in the

bristlecone pines higher on the mountain? What tales canthey tell? I must explain something about mountains thatyou may not remember or know. The higher you go up amountain, or the higher an airplane flies, the colder it isoutside. The bristlecone pine trees growing higher in themountains cannot make food as early in the year as thetrees that are near the lower forest border. When they dogrow the temperatures are cooler too. If the weather isvery cold, the tree cannot make much sugar; and a narrowring is formed or it is missing if it is really cold.

The ring widths in a very old tree near theupper tree line record warm and cold years.

More than half of this tree is dead on thewindward side but the remaining half remains

healthy and strong.


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In warm years,plenty of food ismade and the ringsare wide. Inaddition, theneedles that grow inthe warm years arelonger and theremay be more ofthem. With longand many needlesthe trees can makemore sugar than inyears when thereare shorter and

fewer needles. The trees can keep their needles for asmany as 20 to 30 years. This helps them survive duringlong periods of cold andcloudy weather. When itgets warmer, it may take anumber of warm yearsbefore there are enoughneedles to produce sufficientsugar to grow very widerings. The tree rings tell usabout both occasional coldyears and very long-lastingcold spells in the past.

The number and size of needles fromtrees on cool sites increase and

decrease as temperatures during thesummer change, as shown in a graph

on the right. From V. C. LaMarche, Jr., 1974.

20-year mean growth at lower forest border andupper tree line and the climatic conditions inferred

from the average tree-ring width. Arrows showdates of glacial moraines in the nearby Sierra

Nevada. All but the youngest moraines formedduring cool climates and glacial advances of the

early 1300’s and early 1600’s coincide withunusually wet periods. From V. C. LaMarche, Jr., 1974.


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The ancient bristlecone pine at the upper tree line tell usabout past temperatures during the years the rings grew.The trees at thelower forestborder tell usabout pastsnow andrainfall duringthe years therings grew. Myfriends, C. W.Ferguson, V. C.LaMarche, Jr.,Donald Graybilland GaryFunkhouserwere the scientists that extended the records of pastclimate from both the high and low elevation bristleconepine thousands of years back in time to 6700 BC. ValLaMarche made graphs of these records from A.D. 800 to1960 to infer the changing climate including bothtemperature and precipitation for 1160 years. Then hecompared these inferences about cold and warm years to

the geologicalevidence forclimatic changes.

LaMarch alsostudied and usedfragments of oldtrees lying on theground at

The upper tree line in the White Mountainsshowing many dead fragments above today’s

tree line corresponding with past centuries whenthe climate was warmer than today.

Remnants of old trees growing higher than theupper tree line of today told LaMarche (1973) that

the climate was warmer 2500 years ago.


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elevations above the existing upper tree line. He found thatthere were long periods of warm temperatures when thetrees were able to grow much higher than they grow today.This warmth was followed by cooler temperatures that killedthe highest trees leaving the fragments of these trees thatlie there today.

Scientists have shown that some of the coldest yearswere caused by great volcanoes that exploded, throwingmasses of ash into the sky. There was little sunlight andtemperatures became cold especially during the summers.They also tell us that during very long cool times, whenthere were lots of volcanic eruptions, glaciers, the greatwalls of ice and snow, grew larger and many crops frozethat man had tried to grow on cooler sites. These wereperiods when many people suffered because there was notenough food to eat. Diseases were common; many peoplewere sick. Farms were abandoned and people migrated towarmer places. Historians describe these years as timesof famine. In Ireland a disease favored by damp coolweather killed the potato crop. Many of these Irish peopleabandoned their farms and migrated to the United Stateswhere their descendants live today. If you are Irish, yourgreat great grandparents were probably part of this greatmigration.


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One important tale theseancient trees repeatedly tellis that sometimes the sunshines brightly and life canbe good and sometimesclouds or drought prevailmaking life hard and difficultfor people, especially if theylive in the high mountainsor in dry marginal lands.But these people havelearned, that when life doesget tough, to have courage,do their very best with whatthey have, adapt to thechanges and learn whatthey can. Eventually thesun will shine again, goodtimes will return and theycan be wiser and strongerthan they were before, likethe ancient bristleconepine.

Strong winds can carry iceand may trim our branches,bringing great changes intoour lives, but we can adapt,still go on growing andlearning as we go.

Great volcanoes sometimes exploded,throwing out great plumes of ash anddust into the sky. Here is the Mount

Saint Helens eruption of may 18, 1980.Dust clouds from some volcanoes were

so thick that sunshine was reducedcausing colder weather around theearth. The cold years from earlier

volcanoes are recorded by thebristlecone pine growing on the highest

sites and on other high mountainranges. Their rings were narrow and

sometimes damaged by summer frost.Photograph courtesy of

USGS/Cascades Volcano Observatory


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Remember that thebristlecone pines adaptby losing part of theirbark, leaves and rootswhen conditions aresevere. This reducesthe amount of moisturethey may need tosurvive. They keep ongrowing and living withwhat they still have.They endure these

hardships, become “wise”, very old and remain healthybeautiful trees with lots to tell us about the place wherethey have lived and the conditions in which they grew. Wecan learn about our own inner growth and strength from theexample of our beautiful friends, the ancient bristleconepine trees.

With inner strength and knowledge of their beauty we canbe challenged to create our own bright future. It can be ourchoice to be happy with who we are. Remember the manygood things we already possess and enjoy. Don’t forgetthe many good qualities we may have, qualities that we canuse to create abundance now and in our future. We canchoose to grow stronger and wiser like the ancientbristlecone pine. We can care about each other, our earth,the beautiful trees, crops and animals that support our life.Yes, we can choose to be a looser and complain aboutwhat we don’t have, if that is what we want to be. Howeverwith the higher choice of being a winner, with caring, lovingand working for good along with others that have made this

Glaciers, like this Athabaska Glacier inCanada, grew larger in cold wet years and

melted back in warm dry years.


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same choice, we can create a better future and change ourworld. Yes we can! That is what these ancient andbeautiful trees tell me.

References and World Wide Web Pages aboutthe Bristlecone Pine

Cohen, M. P. 1998. A garden of Bristlecones: Tales ofchange in the Great Basin. University of Nevada Press.308pp. (For the mature reader)

Ferguson, C. W. 1968. Bristlecone pine: Science andesthetics. Science 159:839-846.

LaMarche, V. C. Jr. 1974. Paleoclimatic inferences fromlong tree-ring records. Science 183:1043-1048.

LaMarche, V. C. Jr. 1973. Holocene climatic variationsinferred from treeline fluctuations in the White Mountains,California. Quaternary Research 3:630-660.

Muench, D and Lambert, D Timberlineancients. Charles H. Belding. Portland,Oregon. 128pp. (Photographic treatise)

http://www.sonic.net/bristlecone/intro.html

http://web.utk.edu/~grissino/ The future can bebetter for all of usif we choose it to

be.

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