Bui. 39, Biological Survey, U. S. Dept of Agriculture 





Work of Sapsucker on White Elm and Western Hemlock. 



[1, Radial section through swollen girdle on white elm, showing strong curl of grain. 2, Cross 

 section; checks and stains. 3, Long vertical series of punctures in western hemlock. By, 

 H. E. Burke. 4, Exterior view of healed-over wounds of similar nature. 5, Interior view; 

 extensive stain.] 



