KNOT ZONES AND SPIRAL IN ADIRONDACK RED SPRUCE^ 



By Edward F. McCarthy and Raymond J. Hoyi,e 

 Department of Forest Utilization, Nezv York State College of Forestry 



This study of knot zones, spiral, and other defects in red spruce in 

 the Adirondacks had for its primary purpose the determination of in- 

 fluence of these factors on the amount of spruce available for use in 

 the construction of airplanes. The second purpose was the accumula- 

 tion of data concerning the nature of spiral,^ with the ultimate purpose 

 of determining the cause and the means of control. Notes were made 

 on the per cent of decay and on such defects as pitch seams and pitch 

 pockets. 



AREA STUDIED 



Data have been secured from two sections of the Adirondacks to 

 eliminate the influence of purely local conditions of growth and obtain 

 a check upon variations caused by composition of the forest. The first 

 study included measurements made on 988 trees in southeast St. Law- 

 rence County. Advantage was taken of a pulp-logging operation on 

 the International Paper Company's holdings on the Sucker Brook 

 watershed of Cranberry Lake to secure the measurements recorded. 

 The area is on the north side of the watershed and slopes generally 

 southward over rolling land about Curtis Pond. The second study was 

 made following a pulp-logging operation north of Brandreth Lake, in 

 northern Hamilton County. IVIeasurements were here made on 1,314 

 trees to show spiral per cent and more complete stem measurements to 

 show location of knots were taken on 384 spruce trees. 



TYPE OF FOREST 



All data were taken on the upland type of forest in which beech and 

 maple form a large percentage of the stand. On the Cranberry Lake 

 area balsam does not extend into this type and the per cent of yellow 



' Delivered before the New York Section of the Society of American Foresters, 

 at Lake Placid Club, September 6. 1918. 



- This tendency to growth of fiber that is not longitudinally parallel in the 

 tangential plant' to the axis of the tree is discussed by botanists as torsion. 



NoTK. — The authors wish to recognize the valuable assistance of Prof. Ernest 

 G. Dudley in the collection of the field data. 



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