Bristlecones

Bristlecone Pine, Oldest Known Living Thing

Only recently we have learned that certain stunted pines of arid highlands, not the mammoth trees of rainy forests, may now be called the oldest living things on earth. Microscopic study of growth rings reveals that a bristlecone pine tree found last summer at nearly 10,000 feeet began growing more than 4,600 years ago and thus surpasses the oldest known giant sequoia by many centuries. It stands in the Inyo National Forest, in the White Mountains of east-central California.

Many of its neighbors are nearly as old; we have now dated 17 bristlecone pines (Pinus aristata) [sic] 4,000 years old or more, all in the White Mountains and 9 of them in the area we came to call Methuselah Walk.

Ancient Dwarfs Look Their Age

These oldest pines are now but living ruins. Their trunks, 10 to 30 feet high, are little more than eroded stumps. Yet each possesses its life line, a few inches wide, of bark-covered growing tissue leading from partly bare roots to a thin crown of branches. And each still is able to produce cones occassionally, as it has for well over 4,000 years. The history preserved in their annual layers of growth should eventually give us a unique record of past climatic changes.

20 Years' Research Led to Discovery

The story of the discovery of Methuselah Walk and 4,000-year-old trees really begins some 2 decades ago, when I began hunting long-lived trees in the course of climatic research at the University of Arizona. There Dr. A. E. Douglass long ago had found that trees of certain species show marked variation in ring width, reflecting wet and dry years. This is especially true of the Rocky Mountain Douglas fir and some of the pines.

When cores are taken and growth rings are checked against those in neighboring trees, it is possible to trace the missing rings, extra rings, and other irregularities in growth and to date the rings exactly.

By matching the pattern of wide and narrow rings in the inner part of old trees with corresponding patterns in timbers cut by pre-historic Indians, the scientist can determine when these ancient peoples built their pueblos. Thus, in the 1920's three expeditions led by Dr. Douglass determined the age of Pueblo Bonito, New Mexico, in what is now Chaco Canyon National Monument. These expeditions pushed back the Southwest's historical horizon to more than 800 years before Columbus.

The Indians naturally preferred tall, straight young trees for building timbers. They rarely bothered with the gnarled veterans that here and there clung to a dry sandstone ledge.

Driven, however, by an entirely different need, we began sampling such "worthless" veterans. We were looking for old trees whose growth rings might give us a longer and more sensitive history of past droughts.

| The story continues..... |

Written By: Dr. Edmund Shulman
Dendrochronologist, Laboratory of Tree-Ring Research
Associate Professor of Dendrochronology, University of Arizona, Tucson

Information received from: USDA Forest Service, Inyo National Forest

Edmund Shulman (1908 - 1958) first ventured into the Bristlecone Pine Forest in 1953 at the urging of the Forest Service District Ranger Al Noren, who had heard of Schulman's search for old trees. Dr. Shulman was attempting to extend his continuous tree-ring chronolgy when he sampled some of the trees in what is now called Schulman Grove. His discovery of living 4,000 year-old trees and eventual discovery of the oldest living tree in the world was his reward for years of persistent research.

Dr. Shulman lived to be only 49 years old, but his contribution to the science of dendrochronology and our knowledge of the natural history of the ancient bristlecone trees remains highly significant. In 1959, this area of the Ancient Bristlecone Pine Forest was named Schulman Grove, in his honor. The text in this handout was written by Dr. Shulman before his death as the basis for a landmark article on the bristlecone pines published in National Geographic, March 1958. It has been edited for brevity.