OATS IN THE GEEAT PLAINS AEEA. 39 



Other seasons have been so unfavorable at some stations that no 

 method of cultivation has been able to produce a crop of oats. Less 

 common than either of these are the seasons when there is just the 

 combination of factors nearly or quite to prohibit production by 

 some methods while allowing others to produce good crops. When 

 the results of a series of years are averaged together, as must be 

 done in a continuous agriculture, the wide differences obtained in 

 exceptional years tend to be much reduced. 



Perhaps the first thing that impresses one in viewing the average 

 yields from all stations is the much better adaptation of oats to the 

 northern than to the southern section of the Great Plains. There 

 is an almost constant decrease in yields from the northern stations 

 having cooler, shorter seasons to the southern stations having warmer, 

 longer seasons. This decrease is about the same for the heavier yield- 

 ing as it is for the lighter yielding methods. This proves that there 

 is a lack of adaptation of the crop to the combination of soil and 

 climatic conditions existing at the southern stations. The fact that 

 all methods fail to produce even fair average yields at these stations 

 shows that this lack of adaptation can not be overcome by cultural 

 practices. 



General averages for all of the stations mean little, because differ- 

 ences in yield obtained at one station may be balanced by differences 

 in an opposite direction at another station. 



The division into the two general groups of fall plowing and spring 

 plowing is a striking example of such compensation of differences 

 and the resulting lack of difference in the general average. With 

 the trifling exception of a fraction of a bushel at Edgeley, spring 

 plowing at all stations north of Hays has given higher averages than 

 fall plowing. At Hays and the stations south of it fall plowing has 

 been in about an equal degree better than spring plowing. The 

 greater number of stations represented in the northern group makes 

 the general average of averages show a small margin in favor of 

 spring plowing. This, however, is of no binding force or value to 

 those stations whose results show fall plowing to be the better prac- 

 tice for them. 



At all stations north of North Platte disking has been productive 

 of higher average yields than either fall plowing or spring plowing. 

 At North Platte, Dalhart, and Amariilo it is between the two. At 

 Hays it is the same as fall plowing and higher than spring plowing, 

 and at Garden City it is higher than either. In the general average 

 of all the stations reported it has a yield of 28.3 bushels per acre, 

 against 25.8 bushels for spring plowing and 24.4 bushels for fall 

 plowing. The great bulk of the land disked is corn ground, as is 

 shown in detail in the tables for each station. 



