PINUS 177 



Pine wood was formerly one of the most valuable and 

 at the same time one of the cheapest of soft-wood 

 timbers, but owing to an utter disregard of the prin- 

 ciples of scientific forestry, it is now one of the scarcest 

 and most expensive. Regions that were formerly 

 extensively forested, and the center of a prosperous 

 lumber industry, are now waste land, often occupied by 

 tall stumps, and a source of no profit. It is not neces- 

 sary to destroy the forests in order to obtain an abun- 

 dant supply of lumber, provided only that the crop be 

 harvested in accordance with scientific principles. 

 The conservation of the forests is one of the most important 

 economic problems confronting our country, and excellent 

 opportunities are now offered for well-trained foresters. 



VEGETATIVE ORGANS 



C. The Stem: 



1. In Pinus the shoot, as usual, is composed of the 

 stem and the leaves. The stem is divided into a 

 main part, or trunk, and lateral branches. The 

 entire portion of the shoot, except the trunk, is 

 designated by foresters as the crown 1 of the tree. 



2. The following observations (C, 3-10) of the stem 

 as a whole are to be made out of doors, recorded 

 at this place in the laboratory notes, and handed in 

 at the next class period. 



3. Designate the type of the trunk as excurrent (i.e., 

 extending, entire from the ground to the apex of the 

 tree) or deliquescent (i.e., extending entire for only 

 a short distance from the ground, and then sub- 

 dividing into the numerous limbs and smaller 

 branches of the crown 1 ). 



1 The use of the term crown in this sense is quite ^different from its 

 older use by plant anatomists to designate the region (usually at or near 

 the surface of the ground) whtre the root and shoot join. 



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