Jan., 1921 ACORN-STORING BY THE CALIFORNIA WOODPECKER 5 
that both oaks and acorns were abundantly present all about the pine. Why 
was so much good store room unused? This query was made pertinent by the 
fact that many new holes had recently been made in near-by trees. Undoubt- 
edly the suitableness of the holes for storing suffers impairment with age. As 
the trees grow older, the outermost layers of bark gradually crumble away 
and reduce the depths of the holes so they would need re-drilling to keep ther 
at full depth. Whether such renovation ever really takes place or not, I am 
not certain, but probably it does in some instances. Then, too, occasionally 
holes become more or less filled with pitch. But neither of these sources of 
Fig. 1. NORMAL ACORN-STORAGE BY CALIFORNIA Woop- 
PECKER, IN DEAD BRANCH OF BLUE OAK; PORTION 
PRESERVED IN MUSEUM OF VERTEBRATE ZOOLOGY 
TAKEN BY I. L. KOPPEL NEAR GILROY, CALIFORNIA, IN 
OcTOBER, 1919. 
Impairment applied to very many of the holes in the particular tree to which 
reference is now made. 
By measurements and countings on one of the most abundantly stored 
trees of this lot, I estimated that there was an average of 60 acorns per square 
foot of bark and that in an area of the trunk surface, having an average oirth 
of eleven feet, and a height of twenty feet, there were stored 13.200 acorns. 
Although many nuts could be seen above the elevation indicated. the size of 
the trunk and the irregularity of distribution of nuts made it impractical to 
estimate numbers. Since I shall have oceasion to refer to this particular tree 
