98 BULLETIN 17 4, UNITED STATES NATIONAL MUSEUM 



some of which had been nests in previous years, and some of which 

 had been merely abortive attempts at drilling. The one nest in the 

 oak, referred to above, was in a live tree with a decayed heart." 

 Major Bendire (1895) writes: 



Nidification usually begins about the micldle of May and continues through 

 June. The sexes relieve each other in the preparation of the nesting site, 

 which is usually located in a dead stub of a pine or fir; one that is partly 

 decayed seems to be preferred as it rarely excavates one in solid, hard wood. 

 The nesting sites are seldom situated over 15 feet from the ground, and some- 

 times as low as 2 feet. The entrance hole is about li/^ inches wide, perfectly 

 circular, and just large enough to admit the bird; the inner cavity gradually 

 widens towards the bottom, and is usually from 8 to 12 inches deep, the eggs 

 lying on a slight layer of fine chips, in which they become well embedded as 

 Incubation advances. Occasionally a rather peculiar site is selected. Mr. 

 Charles A. Allen found a nest of this species in a post in one of the snow sheds 

 on the Central Pacific Railroad, between Blue Canyon and Emigrant Gap, 

 about 40 feet from the entrance of the shed, and some thirty trains passed 

 daily within a few feet of the nest, which contained six eggs when found. 



Milton P. Skinner sends me the following notes on nest building 

 by this woodpecker: "On May 10, 1933, I found one at work on a 

 hole in a stub of a tree, about 3 feet above ground. Although this 

 was in the Sequoia National Park beside one of the most used paths, 

 it was deepening the hole for a nest. Chips were scattered on the 

 ground below. After pecking a while, the woodpecker would get 

 into the hole and soon after back out again with a billful of chips. 

 It then opened its bill and let them scatter to the ground ; then back 

 to work again. Although this was as public a place as could be 

 found, and though the birds must frequently have been disturbed by 

 the crowds of people and were within reach of hundreds of children, 

 they succeeded in raising their brood of young. In spite of nesting 

 so low, most of these birds are usuall}^ seen from 20 to 50 feet, and 

 sometimes as high as 100 feet, above ground, working on the trees." 



Of ten nests found by Grinnell and Storer (1924) in the Yosemite 

 region — 



the lowest was located only 58 inches (measured) above ground and the highest, 

 15 feet (estimated). * * * No nest holes of this woodpecker vfeve found in 

 living conifers. Nor, on the other hand, do the birds seek what is commonly 

 known as rotten wood, that is, wood too soft for the nest cavity to be main- 

 tained against the incessant wear involved in the birds' passage back and forth, 

 incident to the rearing of a brood. The tree chosen must have been dead a 

 sufficient length of time for the pitch to have hardened or to have descended to 

 the base of the tree, and the outer shell of the tree must still be hard and firm, 

 whereas the interior must have been softened to a moderate degree by decay. 

 These conditions are not to be met with in every standing dead stub ; hence the 

 choice of a nest site becomes a matter of rather fine discrimination. 



They found plenty of evidence of this discrimination in the many 

 unfinished nesting holes of varying depths that had been abandoned, 

 often several in the same stub. "Some stubs are literally riddled with 



