342 THE POPULAR SCIENCE MONTHLY 



phenomenon, which has almost no counterpart in the coniferous forests 

 farther south, where fires are nearly always ground-fires, and do not kill 

 the trees outright. 



The economic aspects of these northern forests are numerous and 

 varied. The soil and climate are not very favorable for agriculture, so 

 that the farmer, the greatest enemy of forests in this country, has done 

 little damage, and the timber is in no immediate danger of exhaustion. 

 The trees are used to a considerable extent for lumber, and almost as 

 much for pulp-wood ; nearly all the large paper mills in North America 

 being located not far from such forests. Logging is nearly all carried 

 on in winter, when the snow facilitates hauling the logs to the nearest 

 river or railroad. The Christmas trees used in northern cities are 

 nearly all brought from the same region. The same forests furnish 

 our spruce gum and Canada balsam, and among them are found the 

 most important peat deposits in North America. 6 



The boreal conifer region is a favorite resort for hunters, trappers, 

 fishermen, berry-pickers, campers, canoeists, hay-fever sufferers, etc., 

 most of whom migrate northward in summer from the densely popu- 

 lated regions a little farther south. At certain times and places mos- 

 quitoes and black-flies make life in the north woods somewhat burden- 

 some, but the mosquitoes are at least not of the malarial variety, and 

 poisonous snakes and some other pests are conspicuous by their absence. 



The White Pine (Pinus Strobus) ranges from Newfoundland and 

 Manitoba to the mountains of Georgia, and associates with many other 

 trees, mostly hardwoods, in various parts of its range; pure stands of 

 it being the exception rather than the rule. It grows in almost any kind 

 of soil except the richest and poorest, wettest and driest, but seems to 

 prefer that containing a moderate amount of humus. From its distri- 

 bution we may infer that it is confined to climates where the average 

 temperature is less than 55° F., and the growing season not more than 

 half the length of the year: climates pretty well suited for apples but 

 not for cotton. 7 



This species is rather sensitive to fire, at least when young, and per- 

 haps up to middle age. In northern lower Michigan and doubtless else- 

 where there are large areas said to have been covered with white pine 

 forests up to about thirty years ago, when the lumberman came along 

 and felled them. Since then fires, mainly of human origin, have been 

 too frequent to allow the pine to reproduce itself except in protected 

 places like islands and shores of lakes and streams, and the uplands are 



6 Bulletin 16 of the U. S. Bureau of Mines, by Dr. Charles A. Davis, 1911, 

 contains a large colored map showing the distribution of peat in the United 

 States. The Canadian deposits are still more extensive. 



7 The range of the white pine perhaps does not overlap that of the cotton 

 crop at all, though they can be seen within a mile of each other at the western 

 base of the Blue Bidge in northern Georgia. 



