THE GENUS DENDROCTONUS. 



131 



Mr. W. F. Fiske, of this Bureau, who was sent to investigate the 

 conditions as to insect ravages in the White Mountains of the Lincoln 

 National Forest, reported that during his investigations in May, 1907, 

 he found that at least 95 per cent of all of the Engelmann spruce out- 

 side of the burned areas was beetle-killed, but that practically all of 

 this was rather old work and that there was very little evidence of the 

 beetles' presence at that time. 



Mr. J. L. Webb, of this Bureau, visited the same area in September 

 and estimated that fire had killed about 15 per cent of the total stand 

 of spruce, and that the beetle has killed about 90 per cent of the 

 remainder. 



METHODS OF CONTROL. 



The methods of controlling this beetle are essentially the same as 

 for the eastern spruce beetle. 



Fig. 82. — The Engelmarm spruce beetle: Distribution map. (Author's illustration.) 

 BASIS OF INFORMATION. 



Information concerning this barkbeetle is based on investigations 

 by the writer at Boulder, Colo., August, 1901; at Black Hills, S. 

 Dak., September, 1901, and August, 1902, and in the Pike National 

 Forest, Colo., October, 1905; by Mr. J. L. Webb, at Collins, Idaho, 

 September, 1900; in the Black Hills, S. Dak., June and October, 1902, 

 and August, 1906; in the Rincon Mountains, Ariz., and in the Capi- 

 tan Mountains and at Cloudcroft, N. Mex., from May to Septem- 

 ber, 1907; by Mr. W. F. Fiske, in the Capitan Mountains, N. Mex., 

 May, 1907; by Mr. W. D. Edmonston, in the Ouray National Forest, at 

 Craig, Steamboat Springs, and Hahns Peak, in the White River 



