WOODLOT FORESTRY. 19 



It is of value to a forest owner to bring 1 his trees to saw-log size 

 in the shortest possible time. Frequently it has taken fifteen 

 years to re-establish a growth equal in value to a ten-year-old 

 stand which was destroyed. Fire, therefore, must not be tole- 

 rated! 



Grazing must be prohibited in all forest plantings, and in 

 reproduction cuttings, at least until the trees are of such size that 

 their crowns are out of reach of the animals. The young, tender 

 shoots are relished by stock, and an entire year's growth may be 

 lost in a few minutes; moreover, trees thus injured may carry 

 the results through life in the form of crooked stems. 



SILVICULTURE. 



A tree, or a forest, grows and develops well or ill, in response 

 to certain stimuli. In the case of a single tree these influences 

 are reduced to their simplest terms — food, water, light. In the 

 forest they are multiplied and complicated by the struggle of 

 trees, shrubs and herbs each to find the means of life. One who 

 practices forestry takes a hand in this contest, and wisely as he 

 may, checks useless interference, conserves the elements of 

 growth, and stimulates the most valuable trees. After the forest 

 is started his only tools are the ax and saw. It is, therefore, 

 right, not wrong, to use them constantly — and intelligently. 



But the basis of all silviculture is a knowledge of what helps 

 and what hinders the growth of trees. Leaving many factors 

 untouched, the most important may be considered under the fol- 

 lowing heads and then applied to the "Theory of Thinnings." 

 (Page 21.) 



Light. — Without light the leaves of trees are unable to per- 

 form their functions in the elaboration of sap. Some kinds of 

 trees require more light than others. Those whose leaves will 

 function in a weak light are known as tolerant, or shade-endur- 

 ing, while those that require practically full sunlight are called 

 intolerant, or light-requiring. There are many grades between 

 the extremes. Coniferous or evergreen forests are comparatively 



