62 WOODPECKERS IN RELATION TO TREES. 
other words, the distortion of grain is confined to a half circle. An 
ordinary knot lias 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 arc 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 delects 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 tw r o spe- 
cies of this family. In the stinking cedar they are unimportant. 
In the Florida yew, how r ever, their nature and extent are such as to 
ruin both the appearance and the strength of the w T ood. They 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 betw r een annual layers 
very similar to the defect known as cup shake. 
THE CONE-BEARING TREES (PINACF^E). 
This family includes the most important timber trees of the United 
States. We find defects produced in the wood of 29 of the 90 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 overlying 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- 
hind spruce, eastern hemlock, Douglas fir, red fir, and three species of 
1 In this li-t the family suinmarics give general conclusions regarding defects. Full accounts are given 
of species showing typical or severe injuries, and the treatment of each family closes with a list of all the 
in which blemishes or ornaments have been observed. 
Where no locality or museum collection is cited, the specimens referred to are those given in the list of 
lives injured or killed (pp.21 53). Where several specimens of a Bpecies are mentioned iii that list, the 
particular Specimei bare are indicated by citation of the locality or museum initials. The 
I «ord I do not Indicate the total damage done to lumber by sapsuckers, as we have been able 
to examine wood specimens showing defects in only to per tent of the species known to be attacked by 
: ihii lb 1 is by no mean, complete. 
