62 WOODPECKERS IN RELATION TO TREES. 



other words, the distortion of grain is confined to a half circle. An 

 ordinary knot has no such definite relation to the wood layers, and 

 is likely to be approximately circular in section. In rotary cut 

 material and of course occasionally in ordinary lumber (longitudinal 

 sections), bird pecks are cross sectioned, and generally show as trans- 

 verse oblong holes, sometimes filled with loose wood, from which 

 stains run up and down the grain (see figs. 11, 18, and 20). It is 

 probable that the wounds made in trees by other woodpeckers some- 

 times heal so as to present the same appearance as sapsucker pecks; 

 but these generally occur only as isolated blemishes, not in series, as 

 sapsucker pecks nearly always do. Sapsucker pecks vary in economic 

 bearing in different trees according to their abundance, the character 

 of defects and ornaments produced, the uses to which the lumber is 

 put, and its value. 



WOODS IN WHICH BLEMISHES OR ORNAMENTAL EFFECTS ARE KNOWN 

 TO RESULT FROM SAPSUCKER WORK. 1 



THE YEW FAMILY (TAXACE.E). 



Defects due to sapsucker pecking have been observed in two spe- 

 cies of this family. In the stinking cedar they are unimportant. 

 In the Florida yew, however, their nature and extent are such as to 

 ruin both the appearance and the strength of the wood. The}- con- 

 sist of small (one-fourth inch) black stains, accompanied by open 

 knotty checks, gnarly- grain, and long, open resinous seams, which in 

 some cases constitute a complete cleavage between annual layers 

 very similar to the defect known as cup shake. 



TIIK CONE-BEARING TREES (PINACE.E). 



This family includes the most important timber trees of the United 

 States. We find defects produced in the wood of 20 of the 00 native 

 species. Ordinarily these defects vary from small to extensive brown 

 or black, often transverse, stains to open checks up to an inch and a 

 half in length, accompanied by fat streaks, resin deposit, and curled 

 or gnarly grain in the wood layers overbring the healed punctures. 

 Such defects have been observed in the following 12 species: White 

 bark pine, lodgepole pine, long-leaf pine, scrub pine, red spruce, tide- 

 land spruce, eastern hemlock, Douglas fir, red fir, and three species of 



1 In this list the family summaries give general conclusions regarding defects. Full accounts arc given 

 of species showing typical or severe injuries, and the treatment of each family closes with a list of all the 

 species in which blemishes or ornaments have been observed. 



Where no Ideality or museum collection i.s filed, the specimens referred lo are those given in the list of 

 trees injured or killed (pp.21-53). Where several specimens of a species are mentioned in that list, the 

 particular specimens discussed here are indicated by citation of the locality or museum initials. The 

 species recorded do not Indicate the total damage done to lumber by sapsuckcrs. as we have been able 

 to examine wood specimens showing defects in only to per cent of the species known to be attacked by 

 sapsuckers. and thai list is by no means complete. 



