1919] FIELD CROPS. 231 



periment on land treated with clay, 150 or 200 kg. of nitrate of soda and 

 115 l^g. or 230 kg. of sulphate of ammonia per hectare, given in addition to 

 200 kg. each of bone meal and kainit, increased the yields, the better results 

 being from the larger quantities applied. It was found in this experiment 

 also that on limed soil the increases in yield due to these fertilizers were 

 much greater than those on unlimed soil. 



Fertilizer experiments conducted at the experiment station in Syd-Osterbot- 

 ten showed that on bog soil treated with clay and given 150 kg. of bone 

 meal per hectare the use of 2,000 kg. of lime per hectare resulted in a mark- 

 ed increase in the yield of hay. The best yield was 4,776 kg. per hectare, as 

 compared with 1,160 kg. where the soil had been treated with 300 cubic 

 meters of clay per hectare. 



A study was made also at this station of the effect of either oats or legum- 

 inous crops or different mixtures of the same on a succeeding crop of turnips. 

 The crop mixtures varied by 20 per cent of each other as to the proportion of 

 oats and legumes. Yields of turnips were increased from 15,100 kg. per hec- 

 tare where the crop followed oats to 33,127 kg. where it followed a legumi- 

 nous crop. The turnip crop following the mixtures increased in about the 

 proportion the leguminous crops increased and the oats decreased in the 

 crop mixture. 



[Irrigation experiment with, alfalfa and wheat], C. S. Knight (Nevada 

 St<i. li'i>t. ]!)1S. pp. lD-2.1). — This describes further progress of work i>revioiisly 

 noted (E. S. K., 39, p. 132). 



From results secured during the period of 1915-1917, inclusive, it w'as con- 

 cluded that the most economical method of irrigating alfalfa in Nevada is to 

 make 12-in. applications of water when the leaves turn dark-green in color and 

 begin to droop. Under these conditions an average yield of 5.18 tons per acre 

 was secured witli 36 in. of water. The maximum yield, 6.63 tons, was secured 

 with a total of SO in. of water made in 12 in. applications before the plants 

 showed need of water. 



In the wheat experiments, the highest yield per acre and per acre-foot of 

 water for the period of 1914-1917, inclusive, was obtained with four 7-in. appli- 

 cations, the irrigation at the five-leaf stage being omitted. The lowest yield 

 per acre-foot of water applied followed five 7-in. applications. The lowest 

 yields with both 3- and 7-in. applications followed the omission of irrigations 

 at the boot and bloom stages, respectively. Omitting irrigation at two stages 

 of growth, the maximum yield, 32.4 bu. per acre, was oljtained with 21 in. of 

 water made in three 7-in. applications, omitting the five-leaf and dough stages. 

 With both 3- and 7-in. applications the most critical period in the irrigation 

 of wheat was found to be between the boot and milk stages. Where only 

 two irrigations were made the largest yield, 31 bu., was secured from 9-in. 

 applications, one before and one after heading. An application of only 12 in. 

 made in two irrigations produced the highest yield per acre- foot of water, 27.4 

 bu., as compared with 14.1 bu. for 24 in. of water, and 20.7 bu. for 18 in. The 

 average annual precijjitation for the four years of the experiment was 7.52 in. 



See also previous notes (E. S. R., 39, pp. 338. 343). 



Clover and grass seeding' in the conversion of waste land into meadow, 

 A. Grisch (Landiv. Jahrb. Schweiz, 32 (1918), No. Jf, pp. 505-52-i, figs. 3).~ 

 Field tests conducted during 1912-1915, inclusive, are described in which obser- 

 vations were made upon the effect of seeding poorly drained waste lands with 

 a mixture of 14 different sorts of clovers and grasses, and of applications of super- 

 phosphate, Thomas meal, and jwtash In various combinations. It is concluded 

 that by harrowing, seeding with u suitable clover and grass mixture, and apply- 



