Currey originally estimated the tree was at least 4844 years old. A few years later, this was increased to 4862 by Donald Graybill of the University of Arizona's Laboratory of Tree-Ring Research. These ring counts were done on a trunk cross-section taken about 2.5 m (8 feet) above the original germination point of the tree, because the innermost rings were missing below that point. Adjusting Graybill's figure by adding the estimated number of years required to reach that height, plus a correction for the estimated number of missing rings (not uncommon in trees at the tree line), it is probable that the tree was at least 5000 years old when felled. That made it the oldest known unitary (i.e. non-clonal) organism at the time, exceeding even the Methuselah tree of the White Mountains' Schulman Grove, in California, though Methuselah was later redated to 4850 years old.