This central shoot is like a Noah's Ark pine; in time it becomes the tree and finally the basal thicket dies, leaving the specimen in stage No. 3.
A stem of one of the low creepers was cut for examination; it was 11 inches through and 25 years old. Some of these low mats of spruce have stems 5 inches through. They must be fully 100 years old.
A tall, dead, white spruce at the camp was 30 feet high and 11 inches in diameter at 4 feet from the ground. Its 190 rings were hard to count, they were so thin. The central ones were thickest, there being 16 to the inmost inch of radius; on the outside to the north 50 rings made only 1/2 an inch and 86 made one inch.
Numbers 42 and 43, counting from the outside, were two or three times as thick as those outside of them and much thicker than the next within; they must have represented years of unusual summers. No. 99 also was of great size. What years these corresponded with one could not guess, as the tree was a long time dead.
Another, a dwarf but 8 feet high, was 12 inches through. It had 205 rings plus a 5-inch hollow which we reckoned at about 100 rings of growth; 64 rings made only 1 3/8 inches; the outmost of the 64 was 2 inches in from the outside of the wood. Those on the outer two inches were even smaller, so as to be exceedingly difficult to count. This tree was at least 300 years old; our estimates varied, according to the data, from 300 to 325 years.
These, then, are the facts for extremes. In Idaho or Connecticut it took about 10 years to produce the same amount of timber as took 300 years on the edge of the Arctic Zone.
CHAPTER XXXII
THE TREELESS PLAINS
On August 7 we left Camp Last Woods. Our various specimens, with a stock of food, were secured, as usual, in a cache high in two trees, in this case those already used by Tyrrell seven years before, and guarded by the magic necklace of cod hooks.
By noon (in 3 hours) we made fifteen miles, camping far beyond Twin Buttes. All day long the boat shot through water crowded with drowned gnats. These were about 10 to the square inch near shore and for about twenty yards out, after that 10 to the square foot for two hundred or three hundred yards still farther from shore, and for a quarter mile wide they were 10 to the square yard.