70 Forest Club Annual 



records are obtained with the conditions of cover in contrast 

 and simultaneous records with the conditions of cover about 

 equal. Because of the shorter period required and the more 

 certain conditions in bringing about the change the first 

 method seems best. 



Therefore, beginning with the watersheds forested, records 

 should be obtained for a period of two years to bring about 

 a comparison under their present conditions. One watershed 

 should then be denuded, after which its records should show 

 the extreme flood conditions and the large amount of silt 

 brought down at this particular time. When, after several 

 seasons grass begins to appear on the area sheep or cattle 

 might be turned in and the effects of excessive grazing thereby 

 shown. After this the watershed should be allowed to return 

 to its natural forested condition. Any difference that might 

 have been noted in the behavior of the two streams with their 

 conditions of cover in contrast should now decrease propor- 

 tionately as their former similiarity of cover conditions is 

 approached. 



In order to collect the necessary data from which to 

 draw conclusions a rather complicated set of apparatus is 

 needed. It is quite impossible to find two watersheds exactly 

 equal in area, cover, topography and altitudional range, so all 

 calculations should be expressed in percentage. The apparatus 

 used on one watershed should be an exa,ct duplicate of that 

 used on the check area. 



At the lower end of each watershed a dike and settling 

 basin should be constructed. The dike is merely an eight inch 

 wall built across the stream, having bed rock for its foundation 

 in order that no water may pass off without first being meas- 

 ured. That the dike be set on bed rock is highly important 

 since it is found that a large amount of water is slowly flowing 

 downward between the bed rock and the overlying strata, and 

 but for this precaution it would never be measured and a large 

 error in the total flow r would be the result. The surface water 

 and the underground water is obstructed by this dike and 

 compelled to rise until the rectangular opening in the top is 

 reached, there to flow over and be caught in the settling basin, 

 which is constructed just below. The settling basin is for 

 the sole purpose of measuring the silt brought down. The run- 



