EXPERIMENT STATION RECORD. 429 



FIELD CROPS. 



Water requirements of crops in India, II, J. W. Leather (Mem. Dept. Agr. 

 India, Chem. Ser., 1 {1911), No. 10, pp. 205-281, pi. 1, figs. 34).— Earlier work 

 by this author on the same subject has already been noted (E. S. R., 23, p. 331). 

 Tables and charts present data on the amount of water transpired by corn, 

 wheat, flax, barley, oats, gram (Cicer arietimim), peas, sugar cane, and ruta- 

 bagas on various soils, in pots of different sizes, and when treated with various 

 fertilizers. From these and other data presented the author draws certain 

 conclusions. 



The ratios between the amounts of water transpired and the crop weights 

 produced were apparently not affected by the nature of the soil so long as the 

 water supply did not fall below a certain concentration. The concentration of 

 water in the soil required for good development varied with the soil. In the 

 Pusa soil, 10 per cent was sufBcieut for good plants, but in a soil designated 

 by the author as black cotton soil, 25 per cent sufficed only for the most meager 

 growth. The reduction in concentration in the Pusa soil was more or less uni- 

 form for about 5 or 6 ft., below which the change was smaller. After allowing 

 for the moisture which evaporated directly from the soil into the air, a com- 

 parison of the observed decrease of water in a unit column of soil with the 

 crop weight produced gave approximately the same ratio as that obtained by 

 the pot culture method. Thus most of the water required was accounted for 

 by the observed decrease of water within the root range, while the data ob- 

 tained in these experiments may be accounted for by supposing that the quan- 

 tity of water which moves through the soil in a time unit is dependent on 

 concentration, distance, and physical character of the soil. The author believes 

 that temperature also has an important influence and that a laboratory method 

 for the estimate of the soil's water-conducting capacity would be desirable. 



[Dry farming' soil preparation methods], A. E. V. Richardson (Dept. Agr. 

 So. Aust., Rpt. Dry Farming Conf., 1 (1911), pp. IJf, 15). — The results given are 

 for the third year of a test already noted (E. S. R., 26, p. 631). 



During this third season only slight differences could be attributed to varia- 

 tions in time or frequency of subpacking. The 8 plats plowed 6 in. deep 

 gave slightly lower yields than those plowed only 4 in. deep. From the test 

 as a whole, however, the author concludes that subpacking gives a substantial 

 profit under the conditions obtaining at Hammond in South Australia. 



[Field crops at the Delta substation, 1911], G. B. Walkeb (Mississippi Sta. 

 Bill. 157, pp. 3-10, 13-23, figs. 4). — In a variety test of wheat the estimated 

 yields ranged from 16 to 35 bu. per acre, the leading varieties apparently being 

 Blue Stem and IDondike. 



In a fertilizer test with cotton of cotton-seed meal, acid phosphate, and kainit 

 applied singly and in various mixtures, the highest yields and the greatest 

 net increases in value, after deducting the cost of fertilizers, followed appli- 

 cations of (1) 200 lbs. cotton-seed meal and 50 lbs. kainit, (2) 200 lbs. cotton- 

 seed meal, 150 lbs. acid phosphate, and 50 lbs. kainit, and (3) 1.50 lbs. acid 

 phosphate, and 50 lbs. kainit. In a test of applications of lime alone and in a 

 mixture with other materials the yield of 1,366 lbs. of seed cotton per acre 

 followed an application of 1,000 lbs. of lime as compared with 1,516 lbs. on the 

 check plat, and 1,666 lbs. after an application of 200 lbs. cotton-seed meal, 150 

 lbs. acid phosphate, 50 lbs. kainit, and 1,000 lbs. lime. In another test the total 

 seed cotton yield on the check plat was 1,549 lbs. as compared with 1,649 lbs. 

 after what the author terms a normal application of 200 lbs. cotton-seed meal, 

 150 lbs. acid phosphate, and 50 lbs. kainit. A yield of 1,733 lbs. followed an 

 application of double this normal mixture. 



