10 CIRCULAR 421, U. S. DEPARTMENT OF AGRICULTURE 



Listing or "busting out" with a lister in the fall for small grains 

 lessens the expense of fall work but increases the amount of work 

 necessary to prepare a seedbed in the spring. Listing for corn or 

 sorgo, where no fall work is done and when the crop is planted with 

 a lister planter, is much less expensive than plowing. Observations 

 on corn show a smaller growth of stalks and a lower yield of grain 

 from listing in good years. The difference in size of stalk is reflected 

 in the yield of stover. In dry years listed corn generally remains 

 green longer than surface-planted corn. Listing is not to be recom- 

 mended on very heavy soils, as the surface is very likely to crust 

 badly and prevent emergence. 



Prior to 1926 the listed sorgo plot was blank-listed in the fall, 

 and the sorgo was planted in the partly filled furrows the following 

 spring. From 1926 on listing and planting were done as a single 

 operation. Observations on listed sorgo since 1926 show less tillering 

 and a slower growth than for surface planting. Listing for sorgo is 

 not recommended as far north as Ardmore. 



It appears certain that sequence plays a more important part in 

 the production of most crops at Ardmore than does the cultural treat- 

 ment under which they are grown. When only slight differences in 

 yield follow such major differences in cultural methods as those 

 under trial, it seems certain that small differences in cultivation such 

 as disking after harvest and other similar cultural refinements can- 

 not materially affect the yields of grain crops. 



Continuous cropping to grain for so long a period has been possible 

 only because certain noxious weeds, such as wild oats, have never 

 become established in the plots. The continuously cropped flax plots 

 were discontinued in 1928 because redroot amaranth (Amamnthus 

 retrofiexm L.), which does not come up until after the flax has 

 emerged, had become so prevalent that flax yields on these plots were 

 near failures. Continuously cropped winter wheat suffered a reduc- 

 tion in yield in the later years from the prevalence of cornbind 

 (Polygonum convolvulus L.). 



During the first few years, grain grown under a continuous-crop- 

 ping system produced yields approximately equal to those of grain 

 following grain in rotations containing a cultivated crop, but later 

 the yields from continuous cropping were distinctly lower. How- 

 ever, in the year 1927, when soil moisture was ample throughout 

 the season, the yields of most grain crops grown continuously were 

 higher than the average yields of all plots, indicating that the ability 

 of the soil to produce good yields of these crops had not been 

 permanently impaired. 



COMPARISON OF DIFFERENT METHODS OF PREPARING CORN GROUND FOR SMALL GRAINS 



Wheat was grown during the 20-year period on disked corn ground, 

 fall-plowed corn ground, and spring-plowed corn ground. The aver- 

 age difference in yield between these methods was less than half a 

 bushel per acre. This is less than the experimental error. Disking 

 is the cheapest method of preparing corn ground for a crop, and 

 there appears to be no reason for plowing corn ground as a prepara- 

 tion for wheat. 



