1910] FIELD CROPS. 637 



of dry substance In the tnber. In another experiment, conducted on a heavier 

 soil, it was found that irrigation did not increase the yield of tubers to the 

 same extent as in the experiments just described, which were conducted on 

 sandy soil, and the starch content also was increased to only a very limited 

 extent. The percentage of large-sized tul^ers in the crop, however, appeared to 

 have been increased considerably as the result of irrigation. 



In addition to these trials an experiment was conducted with the use of 

 different quantities of waste water from potash works applied with the irriga- 

 tion water. Although as high as 1.2 kg. of chlorin were given per cubic meter 

 of water applied, no injurious effects on the growth and yield of the potatoes 

 was observed, but the foliage was considerably lighter in color than the foliage 

 of the plants irrigated with pure water and the crop ripened about three weeks 

 earlier. 



Sugar beets received a natural precipitation of 237 mm. from May 1 to Sep- 

 tember 30, and were given in addition on certain plats either 130 or 220 mm. 

 of irrigation water. The plat irrigated witli 130 mm. produced 8,300 lbs. of 

 beets and 3,213 lbs. of leaves more per acre than the plat not irrigated. The 

 use of 220 mm. of water apparently reduced the yield of beets and leaves as 

 compared with the application of 130 mm. The results indieatetl that it re- 

 quired an average of 334 lbs. of water to produce 1 lb. of dry matter in the 

 beets and foliage. 



Irrigation of meadows on light sandy soil by the furrowing, flooding, and 

 furrow-gravity methods gave very satisfactory results, the best yield being 

 secured with furrow-gravity irrigation. 



Ten years of variety tests at Dickopshof, A. Richardsen (Landic. Jahrb., 

 48 {1915), No. S, pp. 331-427). — The soil conditions of the experiment field are 

 described, data with reference to the weather conditions for the different years 

 are tabulated, the crop rotations followed are outlined, and the methods of 

 conducting the variety tests with winter and spring wheats, winter rye, oats, 

 barley, sugar beets, fodder beets, ruta-bagas, and potatoes are discussed. The 

 soil devoted to these tests is described as a deep loam with favorable physical 

 characters, although not especially satisfactory from a chemical point of view. 

 The meteorological observations showed a ten-year average of 9.6° C. (49.1° F.) 

 as the mean daily temperature for the year, an annual sunshine total of 1,107 

 hours, and an annual precipitation of 695 mm. (27.8 in.). The results are 

 tabulated in detail for the different years and are summarized for different 

 periods. 



Of three winter wheat varieties grown for seven years, Strube Club gave an 

 average yield of 3,321 kg. of grain and 5,999 kg. of straw per hectare (49.4 bu. 

 and 5.339 lbs. per acre, respectively). Mette Club yielded on the average 3,161 

 kg. of grain and 5,830 kg. of straw per hectare. Strube Club also stood first 

 among the varieties grown for periods of six, five, and four years, but ranked 

 second — Mette Club standing first — among 11 varieties tested from 1911 to 1913, 

 inclusive. In a seven-year test the grain produced by the two varieties repre- 

 sented an average of 35.4 per cent of the total yield, while the average liter 

 weight was 760.3 gm., and the average Vv^eight of 1,000 kernels 37.709 gm. 



From the results secured with spring wheat it is concluded that for the soil 

 conditions of the test, Heine Japhet and Rimpau Red Schlanstedt are of equal 

 valtie and apparently superior to the other varieties tested, while Krafft 

 Bordeaux, Wohltmann Blue Dame, and Iden are considered promising sorts 

 approaching each other in yielding capacity. In one seven-yen r test Rimpau 

 Red Schlanstedt, the leading variety, yielded on an average 2,927 kg. of grain 

 and 5,815 kg. of straw per hectare. As compared with the winter wheat 

 varieties, the spring wheat varieties gave a higher average weight per liter 



