732 EXPERIMENT STATION BECORD. [Vol. 87 



of the association of tiiese two crops was observed in the green appearance of 

 the corn foliage late in the season where co\vi)eas were grown either in tlie 

 row or between the rows, but has not yet been explained. 



Experiments to determine the effect of handling cowpea land in various ways 

 on the wheat crop following indicated that land into which the cowpeas have 

 been worked gave better wheat yields than laud receiving no cowpeas or land 

 from which cowpeas have been cut. Little evidence has been secured to show 

 any deleterious effect of cowpeas on the following wheat crop. 



A study of the factors influencing the development of the maize plant, by 

 M. F. Miller and F. L. Duley, again demonstrated that the middle third of the 

 growing period (from time of laying-by to time of silking) was the mo.st 

 critical from the standpoint of both moistiure and nutrient supplies. The water 

 requirement of the plant was found not to be greatly influenced by the varia- 

 tions iu the supply during the gi-owing period, but to vary greatly with different 

 seasons. The optimum water supply during 1915 gave a weight of ears equal 

 to 36.9 per cent of the total weight of the plant, while the minimum moisture 

 supply gave an ear weight of 17.9 per cent of the total. An optimum supply of 

 plant food gave grain representing 35.8 per cent of the total, while a minimum 

 supply gave a grain weight of only 1.9 per cent of the total. 



[Field crops], F. Watts {Imp. Dtpt. Agr. V,'c^l Indies, Rpt. Agr. Dept. St. 

 Vincent, 1915-16, pp. 5-7, 8-11, lS-13). — Brief notes are given on the results 

 of cotton selections based on tlie mean maximum length of fiber, percentage of 

 available fiber, average weight of seed, and percentage of lint to seed. Fur- 

 ther cotton investigations included studies with crinkled dwarf rogues, inher- 

 itance of the number of teeth in the bracts of cotton, resistance to leaf-blister 

 mite (Eriophye^ gossypii) in budded cottons and in cotton hybrids, Brazilian 

 cotton, and fertilizer tests with Sea Island cotton. 



Attempts to Improve the native corn varieties through selection are reported 

 along two lines, first, to produce uniform yellow corn, aud second, to increase 

 the size of grain and amount of grain per ear. 



The twenty-sixth year of crop experiments, B. K. Lassen, A. HLebstads, 

 H. Foss, and K. Vik (Aarsber. Norgcs Landbr. Hoiskoles Akeivek^tforsok, 26 

 (1914-15), pp. S-65, fuja. 5). — The extension of cooperative field crop testa in 

 1914 is discussed, and the results of several experiments are reported. 



In experiments conducted for five years, potatoes planted about May 15 gave 

 on the average a hij,'lier yield of tubers and a greater i>ercentage of total pro- 

 duction of dry matter than potatoes planted earlier or later. Plantings made 

 about May 7, however, produced the largest tubers. Variations in yearly 

 results were brought about by weather conditions. The late and medium late 

 varieties proved better adapted to early planting than early or medium early 

 sorts. It was found that under the prevailing conditions there was no ad- 

 vantage in planting potatoes, especially medium early varieties, before the soil 

 at 25 cm. (10 in.) under the surface had reached a temperature of from 7 to 8° 

 C. (44.6 to 46.4° F.). The date of planting seemed to have had no influence on 

 the prevalence of dry rot. 



Experiments on the infliheuce of subsoiling to the depth of about 16 in. on soil 

 consisting of a mixture of clay, sand, and gravel, and of a good moisture-hold 

 lug capacity, with a subsoil of a clayey character but not very hard, were con- 

 ducted for six years. The crops grown were turnips, potatoes, peas, spring 

 wheat, and oats. The average results with all these crops showed an increase 

 iu yield from subsoiling, the largest Increase in value being obtained with peas. 

 The average results further indicated that the work had been done at a profit. 



The results secured in an eight-year test of level and ridge culture of root 

 crops indicated that the germination of the seed and the early growth of the 



