72 



WOODPECKEKS IN KELATION TO TEEES. 



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Fig. 20.— Effects of sapsucker work on wood 

 of big shellbark ( Hicoria laciniosa). 

 Stains and gnarly growth. (From Hop- 

 kins.) 



the wood must be sound, and for the latter two uses have few blem- 

 ishes. Many of the species are attacked by sapsuckers, and the 

 resulting defects in the wood are serious. Defects have been found 



in the beech, chestnut, and chinquapin, 

 and in all they are detrimental to the 

 appearance of the wood, and in small 

 pieces they diminish the strength. Or- 

 namental curled grain is sometimes 

 produced in beech, but black cavities 

 and extensive brown stain also are 

 formed, which counterbalance the good 

 effect of the desirable grain. In chin- 

 quapin and chestnut (fig. 22 and PI. 

 IX, fig. 8) large open checks result 

 from sapsucker work, which seriously 

 blemish and weaken the wood. 



In oak, sapsucker blemishes or bird 

 pecks are almost invariably open knotty 

 checks, sometimes small but usually 

 half an inch square or larger. The 

 checks and the immediately adjoining wood are usually heavily 

 stained and the checks are sometimes partly filled or surrounded by 

 loose soft or rotten wood. The wood over the defects is more 

 or less stained and dis- 

 tortecl. Checking 

 through the blemishes 

 commonly occurs, and 

 the weakening of th<' 

 wood is further shown by 

 the tendency of wind- 

 shakes to occur along the 

 line of sapsucker inju- 

 ries. Defects have been 

 observed in the wood of 

 19 oaks, in 17 of which 

 they are serious enough 

 to cause marked loss in 

 value of woods so prized 

 for furniture, in t erior 

 finish, and other orna- 

 mental uses, and in 2 of 

 which, black oak (fig. 23) and cow oak (iig. 24), they arc so large 

 as to spoil the wood for any but the coarsest construction. The 

 large, open, knotty checks so characteristic of sapsucker work 



Fio. 21.— Effects of sapsucker work on wood of hornbeam 

 (Carpinus caroliniana). Small checks and stains. 



