Just how old are these trees? The odd-shaped specimen seen here (some 5m high) was the first measured by Schulman to be older than 4000 years, 4300 to be more precise. 90% of the tree is dead, and the remainder is kept alive by a 25 cm strip of bark. Yet this tree still produces seeds. Age-dating is accurately determined by counting the annual growth rings from cores of the wood. The oldest tree so far discovered is located on the Wheeler Peak, ancient in the White Mountains by 300 years. Since size of tree is no indication of age it is possible that still older trees will be discovered. These trees were alive when the first pyramids were built, 2500 years before the birth of Christ. Other countries have claimed to possess older trees, as a giant cypress in Mexico, but the bristlecone pine remains the most ancient documented organism.