WINTER-WHEAT PRODUCTION AT FORT HAYS STATION. 19 
the other fallow plats are plowed or replowed. Its treatment for 
the remainder of the season is the same as that of the others. The 
same method is followed in the pair R-S except that some time after 
listing in the fall a subsoiler is run in the lister furrows. Un- 
fortunately it was necessary to locate this pair of plats in a block 
in another part of the field. The yielding power of the land is 
about the same, but results can not be compared too closely. The 
yields of these plats are also givenin Table 7. For the 6-year period 
from 1915 to 1920, inclusive, the yield of P-Q has averaged 19.8 
bushels and of R-S 22.2 bushels. In the same years H-I has aver- 
aged 20.1 bushels, J-K 21.0 bushels, L—-M 21.3 bushels, and N-O 
22.9 bushels. 
The results of the whole experiment in methods of fallow show 
clearly that the essential period of the fallow is the summer months 
immediately preceding seeding. This conclusion was indicated in 
the continuous-cropping series by the close approach of the yields 
on early plowing to those on fallow. They also show, in connection 
with other experiments, that the essential part of the fallow is the 
maintenance of a bare surface (prevention of the growth of vege- 
tation) during the active growing season and that the cultural methods 
by which this is accomplished are of minor importance from the stand- 
point of resultant yield. 
} 
TaBLE 7.— Yuelds of wheat from different methods of fallow at the Fort Hays branch 
station for the 7-year period from 1914 to 1920, inclusive. 
Yields per acre by the several methods (bushels). 
par | Bas | Bas | es a 
. -U. — Yl. . iu. 
ae atte April June Fall Halllisted Fallow 
plowed. | plowed. | listed. 3 ie Zo 3 years. 
Year. Plats Plats 
HI. o2K- Plats 
epleg ae pee es (3 i) 26.8 25.6 25.4 7/5 ON | La PE 
eee 0 ee eee 17.3 20. 4 16.8 16.3 19.3 17.8 18.8 
oF Ra i ae 33.6 37.3 38.2 41.2 37.2 38. 0 33. 1 
TAA SEES «hee 6.8 = SS deny 1.0 sd | 11.8 10. 4 
“oh ees ites 3 Sie 15.3 14.1 14.5 18.3 11.8 17.2 28. 8 
RG ed te See 9.0 9.8 10. 2 22. 4 13.7 13.3 9.0 
Mp Te eee eee ee a08 | -lamig7. 8 40. 3 38. 4 28.9 35.0 33.8 
Average, 1914 to 1920..... 2ied| 2G 21.8| 23.6 ].......-.. (OSCE EPS RE EA 
Average, 1915 to 1920..... 20.1 | 21.0 21.3 22.9 19. 8 22.2 22.3 
1 
An experiment started in 1913 to provide material for the study 
of certain water relations of the soil is interesting in its evidence on 
the effect of the length of fallow. On the four plats known as 
rotation No. 570 the land is fallowed for three years and then cropped 
to winter wheat. These plats adjoin the pair R-S in the field. The 
yields from 1915 to 1920 are given in Table 7. The average yield 
for this period is 22.3 bushels per acre, which is less than the highest 
yielding plats with a single year of fallow. The only year when it 
