THE PRINCIPAL SPECIES OF \VOOD. 



INTRODUCTION. 



A TREE has been defined as a woody plant that produces 

 naturally and in its native place one principal erect stem with 

 a definite crown of foliage. A plant thus attaining to the 

 dignity of a tree is said to be arborescent.* 



There are nearly five hundred distinct species of trees 

 growing in the United States, t as well as many others peculiar 

 to other countries, yet the great mass of wood everywhere 

 utilized is derived from comparatively few of them.:}: Many 

 woods will be more generally employed as their valuable 

 properties become more familiar or as the supplies of wood 

 now utilized continue to diminish. 



The same tree is often called by different common names 

 in different places. Nearly thirty names are thus applied to 

 the longleaf pine (Pinus palustris}. Such confusion can be 

 avoided only by regarding the recognized botanical nomencla- 

 ture. 



The botanical name of a plant consists of two principal 

 terms denoting genus and species. Quercus, for example, is 



* Fernow, Introduction to U. S. Forestry Bui. No. 17. 



f Dr. Fernow credits 495 trees to United States (Introduction to U. S. Fores- 

 try Bui. No. 17); Prof. Sargent, counting species only and excluding varieties, 

 gives 422 (Silva of North America). 



\ "The principal timbers of commerce in the United States are the species 

 known popularly as pine, fir, oak, hickory, hemlock, ash, poplar, maple, cypress, 

 spruce, cedar, and walnut." ("The Lumber Trade of the United States," Treas. 

 Dept., Bureau of Statistics.) 



