166 



ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



Table 5 classifies the total number of fires in 1915 according to 

 areas burned over, losses, and causes: 



Table 5. 



Extent of fires and amount 

 of damage. 



Under 0.25 acre 



Between 0.25 and 10 acres 



10 acres and over; damage un- 

 der $100 



10 acres and over; damage $100 

 to $1,000 



10 acres and over; damage 

 over $1,000 



Total 



Causes of fires. 



Railroads 



Lightning 



Incendiarism. . 

 Brush burning 



Campers 



Lumbering 



Unknown 



Miscellaneous.. 



Total.... 



Number. 



560 

 1,799 

 682 

 704 

 1,141 

 169 

 988 

 281 



Per cent 

 of total. 



6,324 



8.86 

 28.45 

 10.78 

 11.13 

 18.04 



2.67 

 15. 62 



4.45 



100.00 



As will be seen from Table 5, 72 per cent of the fires were extin- 

 guished before 10 acres had burned over, and 44 per cent were con- 

 fined to areas of less than one-fourth of an acre. The number of 

 fires threatening the National Forests and successfully confined to 

 outside areas was 1,127. 



The percentage of fires of known origin attributable to human 

 agencies was 59, the slight increase over 1914 being directly traceable 

 to campers, who caused 18.04 per cent of all fires in 1915, as against 

 15.61 per cent for the five-year period. This increase is accounted 

 for by the vastly increased use of the Forests for recreation purposes. 

 The fires caused by railroads were only 8.86 per cent of the total, as 

 against 14.44 per cent for the five-year period. 



Protection of the National Forests includes not only their protec- 

 tion against fire, but also the control of insect infestation and tree 

 diseases. Both of these raise large and difficult technical problems 

 of forest management, which are receiving careful attention. For 

 the basic knowledge in the fields of entomology and plant pathology 

 necessary to the working out of these problems the Bureaus of 

 Entomology and Plant Industry are looked to as the sources of 

 information. In general, control of insects and fungous growths is 

 practicable under existing conditions on the National Forests only 

 through the working out of methods of utilization which will secure 

 the removal of infested or infected material in connection with sales 

 and free use of timber. Stipulations planned to bring about im- 

 proved sanitation of the forest "growth are, where necessary, inserted 

 in timber-sale contracts and special efforts are made to inaugurate 

 sales on areas where a clean-up is important. 



REFORESTATION. 



The work of reforestation was somewhat curtailed during the last 

 fiscal year on account of unfavorable weather conditions in certain 

 portions of the West and on account of some losses in the forest 

 nurseries. This reduced somewhat the total acreage reforested 

 below the 14,000 contemplated in the annual planting plan. Alto- 

 gether, 10,396 acres were reforested. 



Aside from the planting projects conducted in the sand-hills region 

 of Nebraska, the projects initiated for intensive investigative study, 



