34 SURVEYS OF FOREST RESERVES. 



be employed upon the west side of this reserve, aud the same expert may make 

 examinations in the Cascade Range to tho southward, touching the question of the 

 effect of sheep husbandry upon the forests. * 



You are authorized to make such journeys as may be necessary in carrying out 

 these instructions, either by rail or by other mode of public or private conveyance, 

 and to authorize the persons employed by you to make similar journeys. 

 I am, yours, with respect, 



Chas. D. Walcott, Director. 

 Mr. Henry Gannett, 



Geographer, Vnited States Geological Survey. 



Appendix C. 



Department of the Interior, 

 United States Geological Survey, June 15, 1897. 



instructions relative to mapping wooded areas. 



(1) Topographers will map on their iield sheets the outlines of all wooded areas 

 with as great detail and accuracy as they locate other topographic features. 



(2) In the prosecution of plane-table triangulation angles of wooded areas, promi- 

 nent trees aud other features in the boundaries of woodland should be located, to 

 aid in sketching. Traversemeu should locate similar points. 



(3) In topographic sketching the topographer should, with the aid of the control 

 points furnished by his topographic base, as well as those above mentioned, sketch 

 the outlines of all wooded areas, using a symbol which will not conflict with those 

 employed in representing other features. 



(4) The topographer must use his judgment in distinguishing the limits of wooded 

 areas. It is impossible to give rules applicable to all cases, but it is not intended, on 

 the one hand, to limit these areas to large merchantable timber, nor, on the other 

 hand, to include brush or scattered trees. 



(5) The topographer should make notes of the characteristics of these wooded 

 areas — that is, whether they are composed mainly of conifers or of broad-leaved 

 trees. He should distinguish between cedar, piiion, and quaking aspens on the one 

 hand, and pine, spruce, and firs on the other, as well as between chaparral, mesquite, 

 and large timber. 



(6) Burned areas should be noted. 



(7) In the offloe the topographer will draw, on a photograph of the topographic 

 atlas sheet, the outlines of all wooded areas, noting in the body of the map or on the 

 margin such distinctions in the character of the trees as have been above referred to. 



