RESEARCH METHODS IX STUDY OF FOREST ENVIRONMENT. 
77 
After drying, each soil can should be immediately covered and 
weighed. 
The moisture percentage should be determined on the basis of dry 
weight of soil, by deducting the can weight from the dry weight, 
deducting the dry weight from the wet weight, and dividing the 
Fig. 
-Ordinary soil cans, for collection of moisture samples, with covers removed. 
Size 2^ by 21 inches. 
second remainder by the first remainder. Moisture percentages are 
usually worked out to one or two decimal places. 
Soil cans in continuous use should be weighed at least twice each 
season, preferably at the beginning and middle of their periods of 
use. Aluminum cans, while satisfactory in most respects, wear 
appreciably in a few months. 
