10 



BULLETIN U3, U. S. DEPARTMENT OF AGRICULTURE. 



contain a high percentage of flat fragments of shale and sandstone, ranging 

 from 1 or 2 inches to a foot or more wide. In addition, a considerable quantity 

 of finely divided shale fragments is found in both soil and subsoil. The subsoil 

 usually rests at varying depths below 18 inches on beds of shale or sandstone 

 rock. The type is derived from the weathered products of the shale and sand- 

 stone, reworked by glaciation and slightly modified by extraneous glacial ma- 

 terial. It occupies rolling and hilly land and is frequently interrupted or 

 bordered by steep slopes not suited to agricultural purposes. The Volusia silt 

 loam where properly cultivated is a good soil for timothy and small grains. In 

 the eastern part of the region where it occurs it lies at too high an elevation to 

 be well adapted to corn. In this region buckwheat and potatoes are grown to 

 advantage. 



Each of the above soils was treated with applications of the slag 

 fertilizer, and wheat seedlings were planted. The plants were grown 

 for a period of three weeks and then weighed and compared with 

 those grown under similar conditions in untreated soil and in soil 

 treated with other forms of potash and phosphatic fertilizers. Since 

 the Volusia silt loam responds readily to treatment with lime, two 

 sets of experiments were run with this soil. In the first no lime was 

 used except that furnished by this slag fertilizer, but in the second 

 set of tests the soil was limed at the rate of 2 tons to the acre. This 

 was done in order to make sure that any beneficial effect observed 

 from the slag treatment was not entirely due to the basic character 

 of this material. 



In Tables VI, VII, VIII, and IX the results of these experiments 

 are* given. The weight of the untreated plants, or checks, is taken 

 as 100 ; and the weights of the plants grown under similar conditions, 

 but in soils treated with various potash and phosphatic fertilizers, 

 are compared with this figure. 



Table VI. — Relative green weights of wheat plants groivn for a period of three 

 weehs in Garrington silt loam untreated and treated with various quantities 

 of potassic and phosphatic fertilizers. 





Application per acre. 



Relative 



green 

 weights. 



Average. 



Treatment. 



K 2 0. 



P2O5. 



Check 



Pounds. 



Pounds. 



100 

 101 

 104 

 107 

 100 

 113 

 106 

 101 

 107 

 114 

 110 

 110 

 108 



100 



Slag(33SB) 



50 

 100 

 200 



50 

 100 

 200 



60 

 120 

 240 



1 



Do 



!• 104 



Do .. 



1 







Do 





> 106 



Do .. 









60 

 120 

 240 



60 

 120 

 240 



1 



Do 





[• 107 



Do .. 









50 

 100 



200 



1 



Do 



\ 109 



Do 



f 







