532 JOURNAL OF F0RE;STRY 



showing clearly the limits of grazing areas, making much easier the work 

 of estimating the forage. This advantage is present even where there 

 are topographic maps available, and might be great enough to warrant 

 making aerial mosaics in connection with all grazing reconnaissance. 



Likewise, in the case of extensive timber estimating, especially where 

 suitable maps are not available, the aerial mosaic should be of great help. 

 It would be accurate enough for all purposes and would show the bound- 

 aries of all timbered areas. Further, if stereoscopic pictures were 

 made, a man familiar with the region could undoubtedly gain a very 

 good idea of the actual stand from the photographs alone. 



Finally, there are many areas in the heart of the National Forests on 

 which no surveys or reconnaissances have been made, and, if the present 

 methods are to be followed, it is probable that a large part of these areas 

 cannot be mapped for many years to come. Mosaics of the lake and 

 glacier regions might be of considerable value in the service work of 

 promoting recreation uses of the Forests. 



Aside from the several forms of reconnaissance, aerial mosaics or 

 maps of the National Forests would be of assistance in various phases 

 of forest administration. Thus the supervisor would undoubtedly find 

 many uses for a map of this character in planning trails and roads, drift 

 fences, and other grazing improvements, and in aiding tourists and 

 others in finding their way about. In fire-fighting, large scale maps of 

 the region in which the fire occurs should be of real help, especially if 

 supplemented by aerial maps of the fire itself. 



If aerial maps were made recurrently, they would afford the best pos- 

 sible permanent record of changes and improvements on the Forests. 



In timber-sale work aerial photographs, whether in the form of maps 

 or simply as oblique pictures, would add very materially to the value of 

 the timber-sale prospectus, since they could be made to show with great 

 clearness and remarkable detail the entire area under consideration. 



While aerial mapping is as yet a practically undeveloped art, especially 

 in its application to peace-time requirements, the writer feels that suffi- 

 cient progress has already been made, and its possibilities as an aid to 

 forest mapping and administration are sufficiently evident to warrant 

 careful study and thorough experimental investigation, possibly in con- 

 nection with the training of military aviators. 



