80 BULLETIN V90, TT. S. DEPARTMENT OF AGEICTJLTUEE. 



USE OF MAPS. 



Preliminary to making a range inspection, all available and usable 

 map data for the areas to be examined should be obtained and assem- 

 bled. The maps should be enlarged or reduced to a scale of 2 inches 

 to the mile, if they are not already this size ; and they should be cut 

 up and mounted on heavy cloth, in order that they may be folded 

 into suitable size for carrying in saddlebags. If blue-line prints are 

 available, these might be made on a specially prepared linen suitable 

 for field use and satisfactory for later plans. 



"While on the ground, the inspector should make it a practice to 

 record on the face of the map by the use of suitable figures, symbols, 

 and abbreviations the most essential facts about range conditions. 

 Such records, of course, must be occasionally supplemented by notes 

 kept in a notebook that can be carried in the field. 



In the absence of suitable maps the inspecting officer will often 

 find it necessary to adopt some means of roughly determining dis- 

 tances and directions. This can be done on horseback by the use of a 

 compass and tally register. In some instances a few prominent points 

 might be located to good advantage by using a traverse board or 

 plane table. The base for such a triangulation system must be a 

 chained base line or previously established points which can be 

 plotted. 



DEGREE OF ACCURACY REQUIRED. 



The field work, as well as the work of arranging the data into 

 usable form, should be sufficiently intensive and sufficiently accurate 

 to serve as a basis for the solution of the principal grazing-manage- 

 ment problems confronting the administration on the areas inspected. 



If a forest is believed to be fully stocked, or even closely approaches 

 that condition, obviously it would be inconsistent to base the rela- 

 tively fine adjustments that would be necessary in such a case upon 

 information obtained through a very general inspection. On forests 

 considerably understocked the necessary adjustments might be made 

 consistently on information obtained through a hurried inspection. 

 On an intensively grazed forest of average size (800.000 acres) one 

 man should spend at least the entire season, say from July 1 to Octo- 

 ber 31, in field inspection if satisfactory results for the Forest as a 

 whole are to be secured. If there are any low ranges used for early 

 grazing on the Forest, the inspection might begin late in May or early 

 in June. This is usually the best time for the examination of lamb- 

 ing ranges and other early spring ranges. 



TIME OF INSPECTION. 



When there is a considerable variation in elevation the inspection 

 should be planned so that each part of the range will be in prac- 

 tically the same stage of development when the examination is made. 



