Vol. XIX JUNK 15, 1920 No. 6 



JOURNAL OF 



AGRICULTURAL 



RESEARCH 



CONTKNXS 



Page 



Effect of Manure-Sulphur Composts upon the Availability 



of the Potassium of Greensand ----- 239 



A. G. McCALL and A. M. SMITH 



(Contribution liom Maryland Agricultural Experiment Station) 



Rust in Seed Wheat and Its Relation to Seedling Infec- 

 tion ---------- 257 



CHARLES W. HUNGERFORD 



(Contribution from Bureau of Plant Industry) 



PUBLISHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE, 



WITH THE COOPERATION OF THE ASSOCIATION OF 



LAND-GRANT COLLEGES 



WASHINGTON, D. C. 



WASHINQTON : OOVERNMENT PRINTINQ OFFICE : ItiO 



