1916] SOILS — FERTILIZERS. 123 



Lone Oak Field, McCracken County. — Experiments on a moderately acid silt 

 loam soil typical of the uplands of the original wooded area of the Jackson 

 Purchase and supporting a rotation of corn, soy beans, wheat, clover, and 

 timothy with crimson clover or rye as a winter cover crop, gave inconclusive 

 results. However, it is considered safe to recommend the use of limestone and 

 phosphate on this soil, preferably together. 



Mayfleld Field, Graves County. — Experiments on a moderately acid yellow 

 silt loam, typical of the untimbered land of the Purchase Region and on which 

 a rotation of corn, oats, wheat, clover, and timothy was practiced, showed that 

 " limestone and phosphates used together are giving decided increases. The 

 effect of limestone and phosphates is very pronounced on the clover sown in 

 the spring of 191-5. In some cases potash has given good increases and in some 

 it has not. . . . Nitrate of soda has given a profitable increase on one oats crop 

 and on one wheat crop. ... It is safe to say that nitrate of soda should not 

 be used as a top-dressing on wheat in this region unless the ground is either 

 fairly fertile or has been treated with phosphate." 



Green m^anuring in the Central Provinces, R. G. Allan (Agr. Jour. India, 

 10 {1915), No. 4' PP- SSO-394, pls. 2). — A review of experience with green manur- 

 ing before wheat in the Central Provinces of India, using as green manures 

 Sesbania, Crotnlaria junccn, Cassia occidcntalis, Psoralca corylifoUa, Dolichos 

 uniflorus, and Vernonia cinerea, is given. 



The re.sults are taken to indicate that in similar climates " earliness of in- 

 version is more important than quantity. The material should be in by the first 

 week of August. It is desirable to sow with the first rains and to use either a 

 quick crop like C juncea or to collect weeds and apply. . . . Success is not 

 likely unless at least 12 in., or better, 16 in., of rain is received after plowing in, 

 while below 9 or 10 in. the results are not safe and the process is definitely in- 

 advisable. The condition under which plowing is done must be kept in mind 

 in judging the results and the effect of getting on the land at the wrong time 

 allowed for, if necessary. 



" When irrigation is available, either earlier sowing of the green crop is 

 advisable, or, if the natural precipitation falls below the minmura of 9 in., the 

 use of water to .supplement the natural precipitation in rotting the green manure. 

 Such irrigation must be applied before, not after, sowing the wheat. 



" In areas where a rainfall of 12 in. after the first of August can not be relied 

 on, some increased fertility can be gained by the growth of a legume and its 

 use for fodder in the monsoon. In this case it is desirable to invert the stubble 

 by mid-August so as to allow of consolidation by the later rains before sowing 

 wheat. ... In areas wifh a rainfall of less than 35 in. of ordinary monsoon 

 distribution, green manuring for a wheat crop is practically out of the question." 



Investigations relative to the use of nitrog'enous plant foods, 1898—1912, 

 J. G. LiPMAN and A. W. Blaiij {New Jersey Stas. BnJ. 288 {1916), pp. 3-126, 

 figs. 11). — This bulletin reports a continuation up until 1912 of the experiments 

 described in a previous note (E. S. R., 21, p. 529) and summarizes the results of 

 the 15 years' experiments. 



It was found that the yield of dry matter and the percentage of nitrogen 

 recovered in the crop were greatest with sodium nitrate, followed in order by 

 ammonium sulphate and dried blood. " Of the various grades of manure used 

 the solid and liquid stood highest in yield of dry matter and the solid, leached, 

 stood higher than the solid, fresh. The highest average yield of dry matter 

 and nitrogen from the main crops, third rotation, was where solid and liquid 

 manure, fresh, was used in conjunction with the 10-gm. portion of nitrate of 

 soda. The second highest yield was where solid and liquid manure, leached, 

 47580°— 16 3 



