BUKEAU OF FOKESTKY. 509 



(4) An investigation, with the assistance of the United States Geo- 

 logical Survey, of the value of the forest as a conserver of the water 

 supply. This includes the determination, first, of the size and condi- 

 tion of the watersheds tributary to large streams rising within the 

 VVhite Mountain region; second, of the effect of forest destruction 

 upon the flow of these streams; and, third, of the amount and value of 

 water power which is available at different seasons of the year or 

 which is already in iise. 



(5) A study of the size, the value, and the character of the lumber 

 industry of the State of New Hampshire. 



CALIFORNIA. 



During the past year a comprehensive study of the forests of Cali- 

 fornia was begun. This work is the result of an act of the California 

 legislature approved March 16, 1903, which provides that — 



The State board of examiners is hereby empowered to enter into a contract with 

 the chief of the Bureau of Forestry of the Department of Agriculture for the 

 purpose of studying the forest resources of the State and their proper conserva- 

 tion, and especially with a view of formulating a proper State forestry policy, to 

 the extent of $15,000: Provided, however, That these expenditures for such pur- 

 poses shall not be in excess of the amounts to be expended b" the various depart- 

 ments of the Federal Government in collaboration. 



The field work is carried on in cooperation between the of&ces of 

 forest management and forest extension, since the study involves 

 these two branches of the work of the Bureau. Seven men are now 

 engaged upon the investigations incident to forest management. 

 These include the collection of data for a forest map of California 

 sliowing the distribution of the important trees and of the great forest 

 types and indicating cut-over forest and chaparral. A careful study 

 will be made of present methods of lumbering to find practicable modi- 

 flcatious which will hasten the production of a second crop upon the 

 cut-over lands. A similar study will be made of grazing and its effect 

 upon the forest, to determine how it may best be regulated. The 

 results of the work will be embodied in a report which will include, in 

 addition to a detailed description of the work done and its results, 

 recommendations for a forest policy for the State of California. 



Studies of Commercial Trees. 



It has been possible during the past year to organize definitely the 

 work of this Bureau in its studies of commercial trees and to extend 

 their scope. With the increased number of trained men available it 

 is now possible to conduct these studies in the best way — by studying 

 each tree with small parties in various parts of its range. Carried 

 out along these lines, the commercial tree studies now being made by 

 the Bureau of Forestry are valuable contributions to our knowledge 

 of North American forests. 



In the studies of commercial trees conducted during the year par- 

 ticular attention was given to finding the average merchantable stand 

 per acre and its rate of increase. The silvicultural characteristics of 

 each tree were carefully studied, as well as those of the trees with 

 which it occurs in mixture. The distribution of the tree, its behavior 

 in mixture, the forest types in which it occurs, and the effect of eleva- 

 tion and other factors upon it were thoroughly investigated. The 

 influence of present methods of lumbering upon its reproduction was 



