FOREST SERVICE. 405 



ice is cooperating in willow culture with the Maryland and Virginia 

 Agricultural Experiment Stations and with the State of New Jersey. 



Fundamental facts and principles of value to the profession and 

 the science of forestry were yielded by a study, completed and pub- 

 lished during the year, wliich brings together all tne facts known 

 with regard to the part which light plays in the life of the forest. 

 This includes the results of investigations at the Forest Service 

 experiment stations. An investigation of the forest regions of the 

 United States, with special reference to the laws of distribution and 

 the fundamental laws of tree growth, was started. 



The preparation of silvical leaflets was continued. Material for 42 

 leaflets w^as prepared. These leaflets both give forest officers in 

 concise form much valuable silvical information and form the only, 

 and an invaluable, source of information for students in forest schools 

 on the silvicultural requirements of western species. 



Dendrological studies of the structural characteristics of woods 

 furnished material for publications dealing with fustic dyewood and 

 its substitutes and adulterants and with "Colombian mahogany." 

 Both the subject of dyewoods and that of the many woods now sold 

 as mahogany, with the result that no standard exists beyond an 

 arbitrary judgment as to whether or not mahogany has actually been 

 furnished the purdiaser, were investigated further. These investi- 

 gations are minor examples of a line of work which aims to obtain 

 the means of identifying all important woods in their commercial 

 forms. 



The distinguishing characteristics of North American gum woods 

 and of the important North American oaks were dealt with in two 

 bulletins published after the close of the fiscal year, and various 

 other publications are under way or planned. Information on this 

 subject was furnished by letter in response to many inquiries; over 

 500 wood samples were thus identified for manufacturers and other 

 wood users. Studies in the geographical distribution of American 

 forest trees were continued. Some of the data gathered and previ- 

 ously on hand furnished the basis for 501 folio record maps, wliich 

 were prepared with reference especially to the needs of forest officers, 

 and 17 folio maps were prepared for the use of the Forest Products 

 Laboratory to snow the range of certain eastern forest trees. One 

 such map was prepared for publication by the Bureau of Plant 

 Industry. The first of a series of forest geographical atlases, which 

 when finished mil form a complete atlas of North American trees, 

 was prepared; the range of our native pines was presented on quarto 

 size maps. The second volume in the series dealing regionall}^ with 

 the forest trees of the United States, which will be entitled "Forest 

 Trees of the Rocky Mountains," was brought to an advanced stage 

 of preparation. 



STUDIES OF FOREST PRODUCTS. 



The work in forest products was put on a new and greatly improved 

 basis through a complete reorganization, planned with a view to 

 utilizing to best advantage the new facilities afforded by the Forest 

 Products Laboratory. This laboratory made possible the concen- 

 tration of work previously scattered, with a corres])onding gain in 

 efficiency. The new laboratory was opened at Madison, Wis., in 



