240 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



The Dendroctonus barkbeetles have continued to be a menace to 

 the standing pine, spruce, and Douglas fir timbers of the Eocky 

 Mountains and Pacific slope wherever control measures have not 

 been adopted and carried out to prevent the spread of local out- 

 breaks, and in the aggregate many millions of dollars' worth of 

 the best timber has been lost. Wherever the methods that have been 

 determined and advised by this bureau have been adopted and car- 

 ried out, most gratifying results have followed. Especially is this 

 the case in and adjacent to areas in Colorado, Montana, Wyoming, 

 Oregon, and California where control work has been done in past 

 years. 



The work that has been done in the Yosemite National Park dur- 

 ing the past three years has resulted in almost complete elimination 

 of these barkbeetles in the yellow-pine and sugar-pine areas. Some 

 of the private owners of large areas of pine timber in California 

 have made an earnest appeal for aid in protecting the timber from 

 the continued and apparently increasing depredations by these 

 beetles. This has resulted in a general understanding between the 

 representatives of the Bureau of Entomology and the Forest Service 

 of this department, the National Park Service of the Interior De- 

 partment, and representatives of a number of private owners by 

 which a survey of the timbered areas of a large part of the State 

 of California is to be made, under the supervision of a representa- 

 tive of this bureau, to determine the character and extent of the 

 depredations and obtain data on which to base recommendations 

 for concerted control operations. 



The work on Long Island, N. Y., against the hickory barkbeetle 

 in the hickories and the two-lined chestnut borer in the oaks, which 

 was completed during the fall of 1916, apparently has resulted in 

 a great reduction in the numbers of these two insects, which were 

 a menace to the hickories and oaks of the island. 



The oak shade and forest trees of the Southern States have suffered 

 severely from the attack of the Eomaleum oak borer in the main 

 trunks and the Prionus root liorer in the roots. Special investiga- 

 tions and experiments carried on during the year have resulted in 

 the determination of many new facts relating to these two insects 

 and of methods for protecting the trees against their destructive 

 work. 



The damage to buildings and forest products by termites, or white 

 ants, has attracted much attention, and the methods of protection 

 that have been determined and advised have been adopted in many 

 cases with excellent results. 



The damage to forest products ty powder-post beetles has been 

 diminished greatly within recent years through the adoption of the 

 methods recommended in publications and correspondence. One 

 of the greatest losses from this class of insects occurred a few years 

 ago in the Army and Navy stores of lumber, oars, handles, tent 

 poles, etc., but since the methods of control and prevention were 

 advised no further complaint has been received of serious damage. 



Heretofore extensive plantations of black or yellow locust have 

 been a failure on account of the locust borer. Experiments carried 

 on during the spring of 1917 with several insecticides, including 

 some new formulas, sprayed on the bark before the young borers 



