32 FIRST BOOK OF FORESTRY 



by cedar, pine, and oak, while the swamp lands are occu- 

 pied mostly by conifers, cedar, tamarack, and spruce in 

 the North ; cedar and cypress in the South, and that the 

 swamp forests of cold countries are more monotonous and 

 more stunted than those of warmer districts. 



Having seen of how much importance moisture is to 

 the tree, it would be of interest to learn how far the tree 

 can correct any deficiency, to what extent it can drain 

 the soil of surplus water or induce a dry soil to take up 

 and hold more moisture. Experience and observation 

 seem to indicate that it does both. 



WHAT HEAT AND COLD DO FOR THE WOODS 



Let us make a trip from the northern boundary of our 

 country to the Gulf of Mexico and see how the forest 

 differs in different places along our route, keeping in mind, 

 however, that we must compare only such forests as are 

 stocked on well-drained lands of similar soils. 



Along the south shore of Lake Superior, where long 

 snowy winters and short frosty summers restrict farm- 

 ing to the raising of grass, oats, and potatoes, the forest 

 of the fertile loam and clay lands consists of a mixed 

 stand of inferior hardwoods and conifers. The hard- 

 woods are principally birch, maple, elm, and basswood; 

 the conifers, white pine and hemlock. Generally there 

 are more of the hardwoods they predominate; but 



