REPORT OF THE FOEESTEE. 25 



FOBEST INSECT INVESTIGATIONS. 



During the year special explorations were made in cooperation 

 with the Bureau of Entomology in the National Forests of Colorado, 

 to locate old and new work of the Black Hills beetle, make estimates 

 of the amount of insect-infested and killed timber, and determine 

 how to control the insect. One result was to show that an outbreak of 

 this insect can be controlled. The prompt and radical measures 

 adopted by Gen. William J. Palmer in cutting and barking beetle- 

 infested timber during the summer and fall of 1905 and the spring of 

 1906, in the vicinity of Colorado Springs and Palmer Lake, checked 

 the spread of the beetle. 



Maps showing the exact location of the beetle-infested and killed 

 timber were prepared for the Forest Atlas, and these made it easier 

 to get rid of this timber by sale. An important result of these explo- 

 rations in the different National Forests was to teach forest super- 

 visors andr'rangers how to detect evidences of insect depredations and 

 the importance of reporting them, with specimens of the insects or 

 their work. 



COMPILATION. 



The section of compilation collects and systematically organizes for 

 practical use existing silvical information from all possible sources. 

 During the past year silvical notes were compiled for 113 new species. 

 These notes now cover 180 species, including practically all the west- 

 em and most of the important eastern trees. They comprise data 

 classified as to range, character of distribution by regions, associated 

 species, habit, soil, moisture, and light requirements, reproduction, 

 planting and thinning, rate of growth, yield, sprouting, and diseases 

 of the various species. Besides the notes on species, general silvical 

 data are on file for 60 National Forests. 



An increasing amount of silvical data is procured in connection 

 with the regular work of the Service. Special annual reports on the 

 silvical conditions on National Forests are now required from tech- 

 nical assistants. Thirty-one of these reports were received in 1906. 



To place its classified data in the most available form for use in the 

 field, the section has begun the publication of silvical leaflets upon 

 the various species. These leaflets contain compilations of all 

 available silvical knowledge and are designed by future revision 

 and addition to form the basis for an American silviculture. During 

 1906 more than thirty compilations on the silvics of western coni- 

 fers were' prepared for subsequent publication as silvical leaflets. 

 Another line of work pursued by this section was the compilation of 

 silvical data on Pacific coast trees in connection Avith the forthcoming 

 manual of Pacific coast trees. 



LIBRABY. 



Of 13,791 books and pamphlets in the library, 4,500 were added 

 during the year and 3,326 were placed in 109 branch libraries estab- 

 lished in the offices of National Forest supervisors. Service manu- 

 script reports are being indexed with the general library index. 



The photographic collection gained 3,009 mounted prints from 

 the States and Territories and 27 foreign countries, and now contains 

 27,471 such prints. Rapid growth has been curtailed by restricting 



