GLOSSARY. 



Accretion. Growth or formation by external additions to the tree. 

 Acorn, The fruit of an oak. 



Albumen. Food stored up in seed with embryo; endosperm. 

 Alternate leaves. A single leaf at a node; not opposite (e.g. 



Willow). 

 Altimeter. An instrument for taking grades, levels, and heights. 

 Angle mirror. ) Instruments for turning of angles in subdividing 

 Ajigle prism. ) land. 



A7inual. Yearly; a plant which reaches maturity and dies at the 



end of a single season (e.g. Pea, Wheat). 

 Annual ring. The layer of wood formed each year. 

 Anther. The pollen-containing sac ; enlarged part of stamen. 

 Arboriculture, The growing of trees for any purpose whatsoever. 

 Arboreous. Tree-like. 

 Assimilation. In plants, the production of organic matter from 



inorganic matter. 

 Axil. The angle formed by the junction of the leaf-blade, bract, 



petiole, pedicle or pedtlncle, with the branch or stalk from 



which it springs. 

 Back-firing. The burning, under control, of material in front of 



a fire to prevent its spreading. 

 Bark. A general term applied to all the tissues outside of the 



wood proper. 

 Basal. Attached to the base. 

 Basal area. The cross-sectional area of a tree near the ground, 



usually taken about four and one-half feet above ground to 



avoid the excessive swelling of the root buttresses. 

 Bast. The woody fibrous tissue of the inner bark. 

 Baummesser. An instrument for measuring the height of the 



trees, height and diameter at any part on the stem of a 



standing tree. 



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