Forest Products Laboratory and the California District of the Forest Service, in 

 cooperation with the University of California through Professor Charles A. Kofoid 

 for the biological aspects of the problem, had in view a study co\ering the harbors of 

 California. Two phases of the project were carried out, involving the experimental 





Fig. 2. Destruction of Douglas fir by Teredo. 



(1) Fender pile of Douglas fir from wfiarf of Shell Oil Co., Martinez, California, pulled 

 November 5, 1920, showing penetration of Teredo navalis in 1920 (?) at ten equidistant 

 sections. Distance from mud line to high water, 29 feet. 



(2) Brace pile from the same wharf in 26 feet of water. Down-stream exposure at left. 



{Shell Oil Co. Photo.) 



testing in the harbors of San Francisco and San Diego of various species of wood, 

 methods of protection, and preservative treatment with different fractions of coal tar 

 creosote. Such studies, however, had been scattered and more or less fragmentary, 

 and the Forest Products Laboratory decided that it was now desirable to bring the 



