Great Basin National Park
Great Basin bristlecone pines (Pinus longaeva), among the oldest trees in the world, occur near treeline in three groves in Great Basin National Park. These trees are remarkable for their great age and their ability to survive adverse growing conditions.
A 4,600-year-old Great Basin bristlecone pine in the White Mountains of California is the oldest known living tree. A bristlecone pine near Wheeler Peak was dated to be more than 4,900 years old in 1964. Unfortunately, before the area became a national park, the tree was cut down and sectioned to get an accurate reading of its growth rings.
Not all bristlecones live that long. Ironically, the oldest trees are the ones growing near treeline where survival is most difficult. Adversity, it appears, promotes long life. These ancient trees grow slowly, one branch at a time. Even their needles can live up to 40 years. Often, a tree will appear nearly dead, with only a thin strip of living tissue clinging to a gnarled, naked trunk. Ordinary trees would decay under those conditions, but slow-growing bristlecone wood has a high resin content, preventing rot. Instead, the wood actually erodes, like stone, from wind and ice crystals.
Bristlecone pines at treeline usually appear mostly dead. Many will be mufti-stemmed and less than 30 feet tall, with only some of the branches and part of the trunk alive. The almost-dead appearance provides a clue to how the trees grow so old. They adjust to the continually changing environment at treeline.
At lower elevations, where conditions are less extreme, bristlecones grow faster and larger, but they die at the tender age of 300 or 400 years.
In favorable years, a bristlecone pine grows as any other tree does, but in unfavorable years, the living foliage dies back until the moisture and nutrient requirements of the remaining foliage match the supply provided by the root system. The dense, resinous dead wood, exposed to winter ice, driven by high winds, becomes beautifully sculpted and polished.
Visiting Bristlecone Pines
The Wheeler Peak bristlecone pine grove is reached by a 1 3/4 mile (3 1/2 miles round-trip) trail from Wheeler Peak Campground. A short self-guided nature trail is in the grove. During summer, rangers lead walks there. Check at the Visitor Center for dates and times.
Please remember that everything natural is protected in a national park, including dead and down bristlecone wood. Some wood on the ground may be thousands of years old and important scientifically. A piece 9,000 years old has been found. Please leave all down bristlecone wood in place.
Distribution in the Park
The Wheeler Peak grove, located northeast of Wheeler Peak, is unusual because it grows on a glacial moraine consisting of quartzite boulders. Most groves grow on limestone or dolomite.
The grove's northeastern exposure is also unusual. Other groves have mostly southerly or westerly exposures.
The largest grove of bristlecone pines in the park is on Mt. Washington. Located in the west central portion of the park, access is difficult. No developed trails exist in the grove.
Some sections of this grove have relatively tall (over 40 feet) bristlecone pines that resemble high-elevation spruce or limber pine more than the typical gnarled treeline bristlecone pines. Unlike the Wheeler Peak grove, the trees on Mt. Washington grow exclusively on limestone. In fact, nearby quartzite areas are notable for their lack of bristlecones.
The most remote grove in the park is on a spur ridge, the divide between Baker Creek and Snake Creek. The terrain is steep and access is extremely difficult. These also grow exclusively on limestone soils, while granitic soils in the area lack bristlecones.
The bristlecone pine's great age and sensitivity to climatic change makes it ideal for tree ring research. By studying annual variation in tree ring growth, scientists can accurately date the time of construction of prehistoric pueblos in the Southwest (in which wooden beams still remain), double check dates from radiocarbon studies, and reconstruct the climate of the Southwest for the past 7,000 years. Dead bristlecone wood is as valuable to scientists as the living tree, since it extends the continuous climate record even farther into the past.
Bristlecone pines are almost always found above 10,000 feet elevation. Remember that at this elevation you should take things a little slower than you would at sea level.
Weather conditions at treeline can change dramatically in a short time. Snow or sleet can occur during any month of the year. In summer, afternoon electrical storms may develop. Take a warm jacket and rain gear. Do not hike on exposed ridges if a thunderstorm is likely.
Details mentioned in this article were accurate at the time of publication