A MANUAL OF FORESTRY 



FOR THE 



NORTH-EASTERN UNITED STATES 



CHAPTER I. 

 SILVICS. 



IN order to approach the subject of Silvics intelligently it will 

 be well for the reader to have in mind the following definitions 

 adopted by the Society of American Foresters. 



Forestry is the science and art of managing forests in con- 

 tinuity for forest purposes, i.e., for wood supplies and forest 

 influences. The main branches of forestry are forest policy, 

 silviculture, forest economy or forest management, forest pro- 

 tection and forest utilization. 



Silvics. A branch of ecology that treats of the life of trees in 

 the forest; forest ecology. 



Silviculture is the art of producing and tending a forest; the 

 application of the knowledge of silvics in the treatment of a 

 forest. 



In any study of forests over a wide range of country, as a whole 

 continent, it must be apparent that climate determines the 

 character of the forest just as it affects the growth of agricultural 

 crops in certain regions or belts. In a small region, such as New 

 England, the climatic factors are less noticeable, but cannot be 

 overlooked. 



The average temperature of a region is of less importance in 

 determining the range of different trees than the lowest and 

 highest extremes of temperature. In these extremes we have 



