BULLETIN "E. 



Influence of Farm Yard Manure Upon Yield and Upon the Water- 

 Soluble Salts of Soils. 



In the comparative study, the results of which are here re- 

 ported, an effort was made to measure the effect of three very 

 moderate dressings of stable manure both upon the yield of 

 crops and upon the water-soluble salts which could be recovered 

 readily from the soils so treated. 



The amounts of manure applied were at the rates of 5, 10 

 and 15 tons per acre, and these quantities were applied to 8 

 soil types upon 2-aere areas, subdivided in the manner indi- 

 cated in Fig. 1. 



The soils selected were the Norfolk Sandy Soil and Selma 

 Silt Loam at Goldsboro, 1ST. O. ; the Norfolk Sand and Sassa- 

 fras Sandy Loam at Upper Marlboro, Ml. ; the Hagerstown 

 Clay Loam and Hagerstown Loam at Lancaster, Penn. ; and 

 the Janesville Loam and Miami Loam at Janesville, Wis. 

 These soils are fully described in the Second and Fourth Re- 

 ports of this Bureau. 



The areas here considered were chosen primarily for a com- 

 parative study of the water-soluble salts of soils and their rela- 

 tions to yields, and the treatments here referred to were given 

 in order to secure differences of yield within the samei soil 

 type. These phases of the study are reported in Bulletins 

 "B"* and "C". As there stated, the soils were specially 

 chosen with the view to having those strongly contrasted in 

 their native productive capacities, in order thatj well marked 

 differences might be dealt with. Such selection, too, is quite 

 as satisfactory for the purposes of the study here made. 



*Bureau of Soils. "B," Amounts of Plant Food Readily Recoverable from 

 Field Soils with Distilled Water. "C," Relation of Crop Yields to the Amounts 

 of Water-Soluble Plant Food Materials Recovered from Soils. 



