THE FOREST CANOPY 45 
fornia are really undesirable for lumber, because of 
their size and the great difficulty and expense attend- 
ing their exploitation. A tree is usually cut when it 
reaches merchantable size. Merchantable size de- 
pends upon the kind of wood, and the purpose for 
which it is intended. The time element and the 
danger to the capital involved worry the private 
owner to such extent that the tree is usually cut.just 
as soon as it can be profitably utilized. 
