1917] FIELD CROPS. 731 



plowed both deep and shallow in the spring and that which had been plowed 

 both deep and shallow in the fall. Fall-plowed sod land gave slightly increased 

 yields, while shallow fall plowing gave higher yields than deep fall plowing, 

 both giving higher yields than spring plowing. Deep spring plowing gave 

 much higher yields than shallow spring plowing. 



Rate-of-planting tests and variety and breeding tests witti wheat are reported. 

 On the Shelbina field a seeding rate of S pk. per acre gave the highest yield, 

 with the 7-pk. rate second, slightly decreased yields being recorded for the plats 

 seeded at 5- and 6-pk. rates. The 10 leading wheat varieties at Columbia for 

 the season of 1915 were Rudy, Lebanon, Harvest Queen, E\il caster, Deitz, Pride 

 of Genessee, Michigan Amber, Nigger, Pride of Indiana, and Gold Coie. In 

 selection work the two best lines yielded 48.25 and 50.14 bu. per acre, 

 respectively, while the original strains from which they were chosen yielded 

 31.45 bu. per acre. 



Tests with winter oats were continued, some of the hardier strains giving 

 promise for the future. An increased yield of 7.5 bu. per acre was obtained 

 with oats sown on spring-plowed land as compared with the seedings on land 

 disked and harrowed. Drilling in a seed bed prepared by disking and har- 

 rowing increased the yield over plats broadcasted and disked in by 8 bu. per 

 acre, A seeding rate of 12 pk. per acre gave the best results. Variety tests 

 with oats at (Columbia gave an average yield of 44.8 bu. per acre for 24 

 varieties. 



The improvement of winter barley varieties is reported as progressing favor- 

 ably, while spring barley is deemed unsatisfactory at Columbia, due to the 

 short growing season. 



Cotton experiments, conducted by A. R. Evans, included variety and fer- 

 tilizer tests. The five highest-yielding varieties are reported as Christopher 

 Improved, Buck Long Staple, Hamilton Ounce Boll, Simpkin Prolific, and 

 Ozier. The fertilizer tests included a comparison of applications of 200 lbs. 

 of cottonseed meal, 200 lbs. of acid phosphate, and 3 tons of manure, result- 

 ing in increased yields of seed cotton of 470, 340, and 129 lbs. per acre, re- 

 spectively, increases in no case deemed snfficient to pay the cost of the treat- 

 ments. 



E. M. McDonald conducted exi)eriments on the influence of the spacing of 

 rows of wheat and oats upon the yield and quality of grain. The 1915 oat 

 crop was sown in rows, 3, 6, 8, and 12 in. apart, the 12-in. planting giving the 

 highest yield, amounting to about 10 per cent more than the yield from the 

 6-in. planting. The 8- and 12-in. plantings of wheat were expected to yield 

 from 10 to 25 per cent more than the 3- and 6-in. plantings in 1916. 



This year completed the twenty-seventh year's work on crop rotation ex- 

 periments conducted by M. F. Miller and R. R. Hudelson. The unmanured 

 com plat yielded 38 bu. per acre as compared with a yield of 45.7 bu. for the 

 manured plat. The average yield for the untreated plat for the last six years 

 was 1L14 bu. and for the treated plat 28.52 bu. per acre. The relatively high 

 yield of the last year is attributed to the effect of sufficient rainfall. A com- 

 plete fertilizer of 3 per cent nitrogen, 10 per cent phosphorus, and 4 per cent 

 potash gave the highest yield of wheat for all treatments. 



Experiments on the associated growth of com and cowpeas resulted in 

 higher yields of corn grown without cowpeas than when grown with them in 

 the row or between the rows. A slight decrease in the nitrogen content of the 

 corn and stover was noted where cowpeas were grown in the row. Deter- 

 minations of the nitrates in the soil showed that cowpeas grown alone ex- 

 hausted the supply of available nitrates as much as corn, indicating that the 

 oom secured no nitrogen from the cowpeas. A pronounced physiological effect 



