EXPERIMENT STATION REPORTS. 335 



crops in the three-year rotation and the difficulty in securing stands of 

 clover. In the latter rotation soy beans have been planted each year 

 after the failure of the clover. 



In the beets, corn, clover rotation the clover has been seeded in the 

 corn at the last cultivation and under favorable conditions gives fairly 

 good results, but is rather unreliable as a general farm practice. Soy 

 beans were used as a substitute for clover in 1914. In the corn, beets, 

 clover rotation, clover was seeded in the spring in 1911-12 and 13 but 

 was unsuccessful, making an inferior stand and poor growth and being 

 very weedy. Soy beans have been grown on these plats in 1914-15 and 

 16. 



The yields of the plats devoted to the growing of the same plats con- 

 tinuously have, of course, varied considerably according to the seasons. 

 However, a comparison of average yields for the first and second three- 

 year periods, as given in Table 7 will be of interest. 



TABLE VII.— AVERAGE YIELDS OF CROPS GROWN CONTINUOUSLY ON SOME PLATS. 



The average decrease of the above crops from the first to the second 

 three-year period was G3 percent. These plats have already come into a 

 very unproductive condition, in most cases the crop being insufficient 

 to pay the cost of production. This has been especially true in case of 

 the bean plat where the growth has been very small and the disease con- 

 ditions very severe and in the sugar beet plat where it has been impos- 

 sible the past three seasons to secure good stands even by resorting to 

 reseeding and transplanting the beets from a plat of healthy beets. The 

 practice of introducing beans or beets or cultivated crops, or even the 

 small grains, too frequently in the rotation, should be strongly con- 

 demned. 



The average yield of alfalfa, 2.13 tons per acre, is not as high as it 

 should be. It should be explained, however, that this includes the first 

 season of the experiment in which the alfalfa was seeded and no crop 

 harvested, and also that it became necessary to re-seed in 1913 and 1915. 

 The re-seeding was necessitated in part, at least, by the very unfavorable 

 weather after seeding and probably also on account of insufficient sup- 

 ply of lime. 



The timothy in Plat has produced an average yield of 1.23 tons per 

 acre. The timothy has not made a large growth, especially after it has 

 been seeded two or more seasons, and Kentucky blue grass has to a 

 large extent taken possession of the plat. There has been a small 

 amount of volunteer clover and some weeds, also. In 1913 the plat was 

 plowed after removing the crop of hay and re-seeded in September. How- 

 ever, it is again evident that the timothy cannot maintain its possession 

 of this land in competition with the Kentucky blue grass. 



The total value of crops per rotation, as given in Table 8 should not 



