628 EXPERIMENT STATION KECORD. 



where thorough cultivation was given, to 6,989 lbs., or more than 50 

 per cent, where the weeds (mostly pigeon grass) were allowed to grow 

 freel}'. It is believed that the weeds evaporated more moisture per 

 pound of dry matter than the corn. This point is being further 

 studied. 



Compacting the lower portion of the furrow slices with a subsurface 

 packer has had little or no effect in increasing the moisture in the 

 lower portion of the slices, either when the ground was fall or spring- 

 plowed or when coarse manures were plowed under. Subsoiling for 

 corn has apparently reduced the jield of grain 19 per cent and of 

 stover 15 per cent. With wheat the grain yield was slightly reduced 

 and the weight of straw slightly increased on the subsurface-packed 

 plats. Out of 17 comparisons with oats, potatoes, turnips, fodder, 

 corn, wheat, and sugar beets, 14 show a decreased yield from subsoil- 

 ing. The conclusion reached is that " subsoiling is expensive and not 

 profitable under most conditions in Minnesota." 



With wheat the average results for 3 years show equal 3'ields from 

 spring and fall plowing. Practical experience, however, suggests 

 early fall plowing as being more desirable, from the standpoint of 

 economical farm management and weed destruction. A fall-plowed 

 seed bed absorbed more moisture and resulted in an increased yield of 

 2.6 bu. of grain over an un plowed stubble land. The unplowed stub- 

 ble seed bed did not conserve moisture as well as the plowed laud and 

 more weeds grew on it. Harrowing growing wheat when it is a few 

 inches high has resulted in an average decreased yield for 2 years of 

 0.6 bu. per acre. In experiments in broadcasting v. drilling wheat, 

 drilled wheat has averaged 9.5 bu. per acre for 2 j^ears and broad- 

 casted 6.25 bu. The drilled wheat was more deeply and strongly 

 rooted and was less injured by frost. Seeding wheat at the rate of 

 about \ bu. per acre in drills 1-t and 21 in. apart and cultivating 

 between the rows has not given as good yields as the usual method of 

 seeding li bu. per acre in drills 7 in. apart without cultivation. 

 Manuring increased the yield of grain and slightly reduced the ratio 

 of grain to straw. It seemed to decrease the moisture content of the 

 plowed ground the first year, while increasing it the second. 



The moisture content of soils surface cultivated, mulched, plowed, 

 and plowed and subsoiled was studied. "At the depth of 3 to 6 in. 

 the surface-cultivated soil had only about 1 per cent more moisture 

 during most of the season than the soil which was compact to its sur- 

 face, and late in the season it had no more." When the soil was 

 plowed 6 in, deep and subsoiled 7 in. deeper, the moisture in the sub- 

 soil was much better conserved by the loosened earth than in bare 

 compact soil. Plats mulched with a layer of straw ^ in. deep con- 

 tained 5 per cent more moisture than bare soil, fluctuated with 

 weather changes less sharply, and retained their warmth longer. 1 



