DEFECTS IN WOOD CAUSED BY SAPSTJCKERS. 57 



produced during the healing of sapsucker wounds, such as small 

 sound stains, curly grain, and a form of bird's-eye. 



The earliest communication we have on this point is from Charles 

 Eshorn, jr., of Medora, Ind. On May 27, 1892, he wrote to the 

 Biological Survey as follows: 



[The sapsucker] ruins a great deal of valuable forest timber, namely, oak and hick- 

 ory, by pecking holes. ... As the tree grows these places decay, which renders the 

 timber unfit for spokes, staves, etc. These birds are not very numerous, but it seems 

 that each individual can do a great deal of mischief, and should the country be over- 

 run with them they would be a great drawback to the timber business. 



The relation of sapsuckers to lumber was first studied by Dr. A. D. 

 Hopkins while he was connected with the West Virginia Agricul- 

 tural Experiment Station. He discovered that curly and bird's-eye 

 wood are often caused by injuries to living trees by woodpeckers. 

 Dr. Hopkins read a paper on the subject before section F of the 

 American Association for the Advancement of Science, 1 and another 

 before the American Forestry Association in August, 1894, and he 

 spoke on the same subject at a meeting of the Biological Society of 

 Washington March 25, 1902. Dr. Hopkins has generously turned 

 over to the Biological Survey the manuscript and photographs 

 illustrating the latter communication, in addition to his large col- 

 lection of wood samples showing woodpecker work. This collection, 

 augmented by material gathered by the writer in the field or exam- 

 ined in various museums, forms the basis of this section of the 

 bulletin. 



In his address on "Ornaments and blemishes in wood caused by 

 insects and birds," 2 Dr. Hopkins says: 



Blemishes or defects appear in lumber and wood finish as discolored spots, checks, 

 dark stains. resin deposits, pinholes, wormholes, etc., and in the trees as scars, decayed 

 spots, and hollow trunks. 



Ornamental conditions appear in the lumber and inside finish and furniture as 

 so-called bird's-eye, curly, burl, and wavy or satined effects and on the surface of 

 the wood beneath the bark a3 artistic and curious carved and embossed work. 



Twenty or thirty years ago, when the choicest material could be selected from an 

 abundant and cheap supply, blemishes were rarely seen, even in the cheaper finished 

 products. Within recent years, however,, the supply of choice lumber free from defects 

 is becoming so scarce that none but the most expensive finished articles are entirely 

 free from them. Indeed, it would be difficult to find a recently constructed public 

 building or private residence which does not show in the natural wood finish one to 

 many blemishes, the result of various causes. Most of them which are not natural 

 conditions in the wood are caused primarily by insects, birds, mammals, and various 

 other agencies which produce wounds in the cambium of the living tree. 



1 Hopkins, A. D., Some interesting conditions in wood resulting from the attack of insects and wood- 

 peckers. Proc. Am. Assn. Adv. Sci. 1894, p. 252 [abstract]. Excerpts from this paper were published 

 by Dr. Hopkins under the title ' ' The Relation of Insects and B irds to Present Forest Conditions, " in Garden 

 and Forest, VII, 348 and 373, 1894. Its subject matter was brought before the Biological Society of 

 Washington by I'rof. C V. Riley, Dec. 15, 1834, in a paper entitled "Some Interesting Results of In- 

 juries to Trees;" and a review by II. C Hovey appeared in the Scientific American, LXXI, 163, 1894. 



2 Meeting of Biol. Soc. Wash., Mar. 25, 1905. 



