144 EXPERIMENT STATION KKCOKD. 



and [iliiisiili(iiic acid, ami jdiosiilHiric aciil aixl ]>«)tasli, witc aliiiufst ei^ually good, 

 while the plats rweiviiig nitroixcii and potash gave a smaller total yield and a 

 decidedly smaller yield <if grain. Dried blood was more effective than either nitrate 

 of soda or sulphate of ammonia. The aj)plication of 4H lbs. of nitrogen per acre 

 resulted in more grain than either a greater or smaller (juantity. The yield of straw 

 increased with the (piantity of nitrogen applied. Of the different (piantities of l)arn- 

 yard manure api)lied ](),000 lbs. j)e^r acre i)roduced the best total yields. Lime used 

 alone diminished the yield of grain but increased the yield of straw. "Where 4,000 lbs. 

 of lime was used in addition to 12,000 lbs. of barnyard manure the total yield and 

 especially the yield of straw was increased as compared with the use of the manure 

 alone. Ground limestone gave a decided increase in t'.ie yield of straw and a sliglit 

 increase in the yield of grain. Land plaster was less effective than ground limestone. 



Wheat. — The 3 essential elements ai)plied singly ranked in effectiveness in the same 

 order as in the test with oats. In total yield the application of the elements in 

 coml)inations of 2 ranked as follows: Phosphoric acid and nitrogen, phosphoric acid 

 and potash, and nitrogen and potash. Increasing the (juantitj- of nitrogen increased 

 the total yield. The largest and smallest applications of barnyard manure gave the 

 largest and smallest total yields, respectively, on the manured plats. Lime and 

 manure slightly increased the yield of grain over manure alone. Lime applied alone 

 gave a small increase in total yield as compared with the unfertilized plats. Ground 

 limestone was more effective than either lime or plaster. Of the 3 forms of nitrogen 

 dried blood gave the largest yield of grain and sulphate of ammonia the largest yield 

 of straw. 



TbiKAluj and clover. — Phosphoric acid, jiotash, antl nitrogen applied singly ranked 

 in effectiveness in the order given, and where the elements were api)lied in combi- 

 nations of 2 the order was as follows: Phosphoric acid and potash, nitijjgen and 

 phosphoric acid, and nitrogen and potash. Where the nitrogen of the complete fer- 

 tilizer was applied in the form of dried blood the largest yield was obtained from an 

 application of 45 lbs. of this element, but where it was applied in the form of nitrate 

 of soda or sulphate of ammonia the use of 24 lbs. gave the highest yield. Barnyard 

 manure gave the best yield on the plat, receiving 16,000 lbs. per acre. An applica- 

 tion of 4,000 lbs. of lime to supjilement 12,000 lbs. of barnyard manure increased the 

 yield. Lime alone comj)ared with the jdats receiving no fertilizers reduced the 

 yield, while ground limestone and plaster each gave a slight increase. 



MhceUaneous — Corn removed the largest quantity of nitrogen from the soil, fol- 

 lowed by hay, wdieat, and oats, in the order given. With respect to the quantity of 

 phosphoric acid and potash removed, the crops stood in the following order: Com, 

 hay, oats, and wheat. In every instance more nitrogen was removed by the crops 

 than was furnished in the fertilizer, and in every case but one more phosphoric acid 

 was furnished than was removed. Potash, except where applied in the barnyard 

 manure, was also given in excess of tiie quantity removed in the crops. 



In these expenments a mean temperature for the grownig season rather below 

 than above the normal was found most favorable to the growth of corn and wheat, 

 and one rather above than below the normal was best for oats and corn. Precipita- 

 tion rather above than below the normal for the growing season gave the hitrhest 

 yields of corn, wheat, and grass, and when below rather than above the normal the 

 largest yields of oats. 



A five-year rotation of crops including- clover, H. J. Wheeler and G. E; 

 Ad.\ms [RJiode Island Sla. Rpt. 1902, pp. 305-331). — The results of an experiment con- 

 ducted on 5 plats of exhausted soil for the purpose of demonstrating the value of 

 rotation in the renovation of soils are reported at some length. The rotation was as 

 follows: Indian corn on grass sod, potatoes, winter rye, (dover, and grass. The 5 

 different plats introduced into the rotation successively showed the whole course of 

 the rotation in any given year. The work has been in progress for over 5 years and 



