12 



WOOD AND FOREST. 



Not all of the "conifers" bear cones. For example, the juniper 

 bears a berry. The ginko, Fig. 2, tho classed among the "conifers," 

 the "evergreens," and the "needle-leaf" trees, bears no cones, has 

 broad leaves and is deciduous. It has an especial interest as being 

 the sole survivor of many species which grew 

 abundantly in the carboniferous age. 



Also, the terms used by lumbermen, "hard 

 woods" for broad-leaved trees and "soft woods" 

 for conifers, are still less exact, for the wood 

 of some broad-leaved trees, as bass and poplar, 

 is much softer than that of some conifers, as 

 Georgia pine and lignum vitae. 



Another classification commonly made is 

 that of "endogens" (inside growers) including 

 bamboos, palms, etc., and exogens (outside 

 growers) which would include both conifers and 

 broad-leaved trees. 



One reason why so many classifications have come into use is 

 that none of them is quite accurate. A better one will be explained 

 later. See p. 23. 



As in the study of all woods three sections are made, it is well 

 at the outset to understand clearly what these are. 



The sections of a tree made for its study are (Fig. 3) : 



(1) Transverse, a plane at right angles to the organic axis. 



(2} Radial, a longitudinal plane, including the organic axis. 



Fig. 2. Ginko Leaf. 



A 



A.. 



Fig. 3. 



I?. 



A, B, C, D, Transverse Section. 



B, D, E, F, Radial Section. 



G, H, I, J, Tangential Section. 



A, B, C, Transverse Section. 



A, B, D, E, Radial Section. 



B, C, E, F, Tangential Section. 



