DEFINITION OF TERMS USED IN 

 FORESTRY AND LOGGING 



Taken from Bulletin 61, U. S. Forest Service 



Accretion. Increase in diameter or height; distinguished from 

 increment, increase in volume. 



Advance Growth. Young trees which have sprung up in acci- 

 dental openings in the forest or under the forest cover before 

 reproduction cuttings are begun. 



After Growth. Young trees which have sprung up as the result 

 of reproduction cuttings. 



Angle Mirror. An instrument for turning angles in subdividing 

 land. 



Annual Ring. The layer of wood produced by the diameter 

 growth of a tree in one year, as seen on a cross section. 



Arboriculture... The growing of trees for any purpose. 



Aspect. The direction toward which a slope faces. The eight 

 main points of the compass, N., N.E., E., S.E., S., S.W., W., N.W. 

 are distinguished in forest description. 



Assimilation. In plants the production of organic matter from 

 inorganic matter. 



Back Fire. A fire started purposely some distance ahead of a 

 fire which is to be fought. The back fire is intended to burn 

 against the wind, so that when the two fires meet, both must go out 

 for lack of fuel. 



Ball Planting. A method of transplanting young trees with 

 balls or lumps of earth around the roots. 



Basal Area. The area of a cross-section of a tree, or the sum of 

 such areas. 



Barn Boss. One who has charge of the stables in a logging 

 camp. 



Birl. To cause a floating log to rotate rapidly by treading upon it. 



Blank. An opening in the forest where, from any cause, very 

 few or no trees are growing. 



Blaze. To mark, by cutting into trees, the course of a boundary, 

 road, trail, etc. 



Board Foot. The contents of a board one foot square and one 

 inch thick. The common unit of measure for logs and lumber in 

 the United States. 



Board Measure. The standard of lumber measurement, the unit 

 of which is the board foot. 



Board Rule. A graduated stick for determining the contents 

 of boards. The number of board feet in boards of given widths 

 and lengths is shown upon the stick. Often called scale stick. 



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