BIGTREE 



(Sequoia Washingtoniana) 



BOTANISTS have had a hard time giving this tree a Latin name 

 which will meet the requirements of technical classification, but an 

 English name acceptable everywhere was early found for it bigtree. 

 No fewer than a dozen names have been proposed by botanists. Most 

 of them attempt to express the idea of vastness or grandeur; but the 

 simple English name comes directly to the point and ends the contro- 

 versy as far as the common name is concerned. 



Everything connected with this tree is interesting. Geologically, 

 it is as old as the yellow poplar. There were five species of sequoias in 

 the northern hemisphere, in Europe and America, before the ice age. 

 They grew in the North, nearly to the Arctic circle, at a time when the 

 climate of those regions was milder than it is now. The later advance of 

 the ice southward overwhelmed three species of bigtrees, and pushed 

 two survivors into the region which is now California. These are the 

 bigtree and the redwood. It is not known how long ago it was that the 

 ice sheet did its destructive work, but it antedated human history, and 

 the gigantic trees have been in California since that time. 



Long after the ice age ceased generally in North America it 

 continued among the high Sierras of California, and the bigtrees to this 

 day give a hint of it in the peculiar outlines of their range. They are 

 scattered north and south along the face of the Sierra Nevada mountains 

 in California, a distance of 260 miles, and at elevations from 4,500 to 

 8,000 feet. 



The aggregate of the total areas is about fifty square miles. The 

 stand is not continuous, but consists of "groves," that is, isolated stands 

 with wide intervals between, where no trees of this species are found. 

 The arrangement suggests that the bigtree forest was cut in sections by 

 glaciers which descended from the high mountains to the plains, a dis- 

 tance of one hundred miles or more, crossing the belt of sequoias at right 

 angles. The glaciers withdrew thousands of years ago, and their tracks 

 down the mountain slopes have long been covered by forests; but the 

 bigtree groves, for some unknown reason, never spread into the inter- 

 vening spaces, but today are separated by wide tracts in which not a 

 seedling or an old trunk or log of that species is to be found. This 

 is one of the mysteries which add interest to those wonderful trees 

 why they cannot extend their range beyond the circumscribed limits 

 which they occupied thousands of years ago. 



It was claimed for a long time and was quite generally believed that 



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