ROTATION AND CULTURAL METHODS AT EDGELEY, 1ST. DAK. 7 



On the continuously cropped plats the years favoring fall plowing 

 and those favoring spring plowing have been about equal in num- 

 ber. In rotations where spring plowing is deep the greater num- 

 ber of years have favored fall plowing. Some years have mark- 

 edly favored fall plowing, and others have as markedly favored 

 spring plowing. Measured in bushels per acre the greatest difference 

 shown in any one year was in favor of spring plowing in 1915. This 

 was the year of the heaviest yields in the history of the experiments. 

 The winter and spring were dry until after the crop was up, and 

 there was better germination on the spring-plowed than on the fall- 

 plowed plats. The rains that made the crop did not begin until 

 after the crop was started. 



For corn the evidence is also contradictory, with little or no aver- 

 age difference where corn follows wheat or corn, but appearing to 

 average in favor of spring plowing where corn follows oats. The 

 evidence of section 9 shows an advantage of spring plowing for 

 corn following wheat, oats, and corn. 



The work in hand is not designed to study the question of time of 

 fall plowing. As noted above, there has been during the experi- 

 ments considerable range in the time of fall plowing. It is not 

 possible, however, to identify in the results any relation between the 

 time the fall plowing has been done and the yield as compared with 

 that from spring plowing. 



In these experiments fall plowing and spring plowing are both 

 seeded at the same time. Seeding is usually done comparatively early, 

 the date depending upon the season. But when a large acreage is 

 to be handled plowing in the spring necessarily delays seeding. 

 It has been abundantly proved and is well recognized that delay in 

 seeding in this section decreases yields. This is a section of large 

 acreages. It is, therefore, highly desirable that as much as possible of 

 the land to be seeded to small grains be plowed in the fall, so that 

 seeding may not be delayed. There is, however, no disadvantage 

 and there may even be some gain from spring plowing, provided it 

 does not delay seeding beyond the critical date. The possibility of 

 doing much spring plowing without incurring loss from late seeding 

 depends very much upon the character of the spring. 



The distribution of labor indicates spring plowing for corn, al- 

 though little disadvantage in yield is experienced if the corn be 

 planted on fall plowing. 



All the evidence indicates that for the best results spring plowing 

 should be shallow. 



DISKING COMPARED WITH PLOWING CORN GROUND IN PREPA- 

 RATION FOR WHEAT AND OATS. 



When corn ground is to be sown to small grains it may be plowed 

 in the fall or spring or it may be prepared for seeding without plow- 

 ing. In the latter case it is generally disked. The work at Edgeley 



