94 LIVING PLANTS 



ture does not reach the freezing point, or does 

 so slowly, and rises again so gradually that 

 no harm is done. The primary purpose of the 

 roots is of course to penetrate the soil in such 

 manner as to fix the plant and obtain a sup- 

 ply of mineral salts, and in so doing a region 

 not subject to the rigors of low temperature 

 is reached. Some lowly-growing plants avail 

 themselves of the blanket-like coverings of 

 leaves and snow which fall upon them before 

 the extremest rigors of the winter are at hand. 

 Many plants native in alpine regions arc 

 specially adapted to take advantage of this 

 means of protection. Among them are some 

 of the rhododendrons, dwarf junipers and 

 pines. 



The stem of Pinus hatnilis of the higher 

 mountain slopes, although eight or ten inches 

 in diameter and strong enough to stand erect 

 and sustain the ample crown, grows almost 

 parallel with the surface and a few inches 

 above it. The branches which are ordinarily 

 erect are very flexible and easily bent down- 

 w^ard, and when weighted spread themselves 

 along the ground. This is true of branches 

 which stand up to the height of a yard or 

 more. When the early storms set in, and the 

 ever increasing layer of snow settles down 

 over everything, the branches slowly bend 

 under the constantly augmented weight, and 



