RESEARCH METHODS IX STUDY OF FOREST ENVIRONMENT. 173 



quality, insolation, wind exposure, etc., be witnessed by photographs 

 and topographic map. The former should be taken from as many 

 positions as possible to show the general position of the station with 

 respecl to topographic features, to show the position of the trees which 

 may influence atmospheric factors, to furnish a map of the canopy 

 (by vertical view) which affects the insolation at the ground, and 

 finally to show in detail the nature of the ground and ground cover. 

 The view of the canopy should be taken as nearly as possible from the 

 position which will be occupied by solar apparatus and evaporimeter. 

 The local topographic map should be made on a scale adequate to 

 show in detail the immediate surroundings and those which are close 

 enough to have appreciable effect on insolation, wind velocity, etc. 

 Especially when two or more stations in close proximity, but different 

 presumably in some essential aspect, are being studied, should the 

 map he made full enough to bring out clearly the contrast which 

 exists in conditions. In such cases a joint map for the several stations 

 may well he used. Such maps should, if possible, be restricted to the 

 size of the tabulating Conns used. 



Form 1. 



[('. S. Forest Service, Physical survey.] 



DESCRIPTION OF OBSERVATION POINT. LIMITED AREA, TREE ENVIRONMENT. 



Project — — — -. 



Station No Lrea involved 



Forest type Absolute elevation 



Permanenl sample pint No Bloek No 



National Forest Nearest post office 



County State 



Legal location Exact location 



PHOTOGRAPHIC FEATURES. 



Aspect Gradient 



Distance from ridge Distance from channel 



Elevation above water Wind exposure 



Air drainage condition 



Elevation of horizon to east ; west ; north ; south 



< haraeter of topography 



FOREST ENVIRONMENT. 



Distance of nearest trees to north ; east ; south ; west 



Age of trees Height 



Diameter - Trees per acre 



Stand, feet b. m Stand, cubic feet 



( irowtli rate; height, diameter, or cubic feet per A. A 



Shading, amount From trees on 



Light at the ground, per cent Determined by 



