516 EXPERIMENT STATION RECORD. IV<>1 46 



applications of from 150 to 200 lbs. of acid phosphate produced average gains of 

 from 50 to 185 lbs. Of seed cotton per acre; applications of from 30 to 100 lbs. of 

 cottonseed meal, gains of from 20 to 105 lbs.; and applications of from 5 to 25 

 lbs. of muriate of potash, gains of from 20 to 140 lbs. 



Acid phosphate is deemed to be the most certain and the most profitable fer- 

 tilizer for both cotton and corn, while a mixture of equal parts acid phosphate 

 and cottonseed meal (containing about 8 per cent available phosphoric add and 

 3.5 per cent nitrogen) applied at the rate of from 150 to 2tx> lbs. i>er acre ap- 

 peared to be the best mixed fertilizer for these crops. If 300 lbs. or more are 

 to be used on cotton, it is suggested that the Fertilizer contain about 5 per cent 

 phosphoric acid and 4 per cent nitrogen. The use of potash In mixed fertilizers 

 is regarded as inadvisable except where the soil is known to be deficient in 

 potash. In such cases a mixture containing 8 per cent phosphoric acid and 3 

 per cent each nitrogen and potash is recommended for application to cotton or 

 corn at the rate of from 150 to 2ix> lbs. If larger applications are to be made, 

 it is recommended that the percentage of phosphoric acid be reduced and that of 

 nitrogen and potash increased. Barnyard manure produced average gains of 

 from U>7 to 227 lbs. of seed cotton per acre, and is also said to have given good 

 results with coin, the effects of the manure continuing over several years. 



in it; experiments with cotton the phosphoric acid of roek phosphate was 

 found to have about 22 per cenl of the effect of that in acid phosphate. The use 

 of bydrated lime on cotton resulted in an average decrease of about 6 per cent 

 in - jd tests. Where an equivalent amount of sodium nitrate replaced one-half 

 the cottonseed meal, the yields of cotton were Slightly lower than for sodium 

 nitrate alone. 



The use of cottonseed meal was followed by rains in S7 per cent of the Irish 

 potato tests, of acid phosphate In 72 per cent, and of potash In .".'J per Cent 



Where gains occurred, 400 lbs. of cottons l meal produced gains of from I s t" 



28 bu. per acre; 800 lbs. of acid phosphate from 10 to 24 bu.. and 20 lhs. of sul- 

 phate or muriate of potash from t! to Hi bu. A mixture of 100 Mis. of acid phos- 

 phate wiiii l'im » ihs. of cottonseed meal is said io be the best average Fertilizer 

 for both Irish and sweet potatoes. The use of potash Is deemed advisable only 

 when the soil Is known to he deficient In that Ingredient, and then in combina- 

 tion with acid phosphate ami cottonseed meal. Manure applied to Irish potatoes 



at the rate of L'O loads per acre showed average gains of from 8.9 to 4.5 bu. pei- 

 acre the first 2 years and from .".1 to 88 bu. the last 4 years. Replacing one half 

 the cottonseed meal by an equivalent amount of sodium nitrate gave practically 

 the same results as where cottonseed meal was used alone 



In the sweet potato tests do per cent showed gains with add phosphate and 

 cottonseed meal and 56 per cent with potash. Where trains occurred. 3ix) lhs. 

 of acid phosphate showed gains of from 19 to 71 bu. per acre, 400 lbs. of cotton- 

 seed meal from S to 47 bu.. and 40 lbs. of muriate of potash from 15 to 80 bu. 



Production and consumption of potash fin the United States], P. !\ 

 Houston (('. 8. Semite. <>'>. Cong., .1 S< w«., Doe. 396 (1919), /</». •>'). — It Is 

 stated that the information In the possession of the I". S. Department of Agri- 

 culture "indicates a production in the United States during 1!HS> of about 

 53,600 tons of actual potash (KiO). of this amount, approximately 2s.imm» tons 

 were produced from the brine lakes of western Nebraska, 1 1 ,( M M> from Searlos 

 Lake, Gal., and 2.600 from alunite. ... A conservative estimate would 

 probably show about 5,000 tons of K»0 from kelp ami 7,(><M» tons from all other 



sources, Including cement mills, blast furnaces, smrar mill wastes, and w 1 



ashes." Data furnished by producers Indicate that about 60.000 tons of potash 

 salts containing approximately 15.000 tons of actual potash was in Storage 

 January 1, 1019. 



