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Tahoe Nugget #19:
Bristlecone Forest
The Ancient Bristlecone Pine Forest in the White Mountains east of Bishop, California, was a prime target on my recent road trip. These
venerable Bristlecone pine trees grow in a cold, arid region (average temperature just above freezing and about 12 inches precipitation a year) and at elevations above 10,000 feet. White Mountain Peak reaches 14,246
feet, one of the highest mountains in the lower 48 states. The landscape and climate are extremely harsh, but these obdurate pines are the oldest living things in the world. Carbon dating has proven that some of the
trees in this region are more than 4,000 years old, and still growing. (Note the green foliage behind the tree to the right.) These trees are not dead.
Due to their high sensitivity to variations in annual precipitation, tree ring cores extracted from these ancient pines enable
dendroclimatologists to accurately date wet and dry seasons, as well as long-term climate fluctuations to a remarkable degree. Bristlecone pine wood that has fallen to the ground can remain intact for thousands of
years in the cold, dry climate. Scientists have used a cross-dating technique that overlaps tree-ring patterns of living trees with the dead wood to assemble a climate chronology extending nearly 10,000 years.
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