NORTHERN GREAT PLAINS FIELD STATION, 1913-1922 ye 
Spring plowing for corn is usually done about May 10, and the 
crop is seeded between May 15 and May 20. The crop is cultivated 
usually three times during the season. 
Table 19 shows the yield of ear corn in the main field during the 
eight years 1915-1922. In general, spring plowing after small grain 
has produced, higher ‘yields than fall plowing after small grain, but . 
during favorable seasons the difference in yield is likely to be small. 
Spring plowing for corn is to be preferred because the work usuaily is 
easier, the yields generally are higher, and spring plowing is cleaner 
than fall plowing. Fall-plowed land in this area is likely to be sown 
to wheat if the spring is favorable, even though it were intended. for 
corn at the time of plowing. Subsoiling and listing after corn are 
both inferior to either spring or fall plowing after corn. 
Corn has produced a slightly higher yield on summer-fallowed 
land than on land handled in any other way, but the increase in 
yield is not enough to compensate for the labor and the loss of the 
use of the land during the year of fallow except in a dry season, such 
as 1920. 
With either spring or fall plowing there is not much difference in 
the yield of corn following the different small erains. The desira- 
bility of the small grain itself is of much greater weight in its choice 
than is any effect it may have on a following crop of corn. The yield 
of corn following corn is bigher than following small grain, regardless 
of the method of tillage. 
On the heavier soil in the south field the yields have been less than 
those from comparable plats in the main field. In this field fall 
plowing has slightly exceeded spring plowing in yields. 
The yields of corn stover are not given in the table, but were 
Sightly: heavier than 2,000 pounds per acre. The highest yields 
were following summer ‘fallow and corn. The highest yield after 
small grain was on spring plowing. 
In rotations where manure is put on for the corn crop the yield of 
both grain and stover has been higher than in similar rotations 
where manure was not put on. The influence of the manure has been 
greater on the stover than on the grain. 
TABLE 19.—Yields of ear corn in the main field at the Northern Great Plains Field 
Station following different cultural treatments and crops for the 8-year period, 
1915-1922, inclusive 
| 
iNum-| Yields per acre (bushels) 
ber aes a ries 
Treatment and previous crop ee | | | | 
aver-| 1915 | 1916 | 1917 | 1918 | 1919 | 1920 | 1921 | 1922 | “Ver 
aged | | | ; 
Spring plowed: | 
Suialljorainis ova ete ee 2 8) 29 | 26.6 | 37.6 | 23.1 | 36.3 | 24.9) 69 | 185] 35.6] 26.2 
COMMIS hea 2 ee nner ae 1-| 29.6 | 39.8 | 26.7 | 45.7 | 28.6 | 11.4 | 22.3} 39.6| 30.5 
Fall plowed: 
Siiigli ani see, Sse Seale Sa ages See 160s 2698 | 40) 29ehG. 421-33. 2-|.2050| 3.9 | 13.0 | 28.5 | 22.8 
OSTA Eee hs Rea tee eae ft e260 | 49) lei On 4409° 26.9) |. 7..9)| 2251 | 86.6 | 29.4 
sunnmer fallowed 222222201. 5 aie se4) to: 1 | 25.7 | 34.9 | 28.1 | 46.6 | 30.6 | 24.3 | 35.3 | 40.6 | 33.3 
pMpsoleds Conn sas sexe 8! 2 2. 852225 1 | 24.8 | 44.5 | 18.7} 45.6 | 29.3 | 10.1] 20.9 | 35.6 |} 28.7 
LOTS DG le CYA a oe le Iie 2728 | S6,6n memoria. | 27.1 | t4e7>| 18) 6/3126") +27.6 
Average of all'50 plats. _..---______ Dee fogs h3Rcatomeeseatnlosevele 6 5 |l17. 9 1:33: 5 | 25.5 
| | — 
