FOREST SURVEY FETHOD 



A. The forest resource statistics in this report are based on a field 

 survev made during 1947. Briefly the method used in making this 

 survey was as follows: 



1. The forest area was determined by an area sampling system 

 which involved measuring and classifying systematically 

 distributed sample segments. 



2. The timber volume was determined b^ measuring the trees 

 found on randomly selected one-fifth acre plots located 

 within the sample segments 



B. The basic data from which the area and volume were determined con- 

 sisted of the following field samples: 





: Area 





Volume 



Class 



: Number of: 

 : sample : 

 : segments : 



Area per 

 sample segment 

 (acres) 



: Number 

 : plot; 



: Area per 

 of: sample plot 

 5 : (acres) 



I 



234 



2,560 



702 



1/5 



II & III 



193 



640 



382 



1/5 



C. Distribution of the area sample segments and volume plots was con- 

 trolled by the following method: 



1. The entire area was divided on 1-inch-to-the-mile base msps 

 into three primary classes: 



Class I Areas predominantly forest for which aerial 



photographs were available. 

 Class II Areas predominantly nonforest for which 



aerial photographs were available at moderate 



cost . 



Class III Areas predominantly nonforest for which 

 aerial photographs cost more than $2 per 

 print, or for which there were no aerial 

 photographs. 



2. Each of the three primary classes were further subdivided into 

 units in the following manner: Beginning with a random selec- 

 tion, Land Office section corners were marked on a base map 



at 4-niile intervals for areas in Class I, 7-mile intervals 



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