22 BULLETIN 1173, U. S. DEPARTMENT OF AGRICULTURE. 
Table 11 summarizes the data given in Table 10 and in addition 
shows the yields of winter wheat obtained in the years from 1914 to 
1919, inclusive, after summer fallow plowed in the fall with a disk 
plow and with a moldboard plow. The use of the disk plow was dis- 
continued after 1919. In Table 11 the annual yields from the fall- 
plowed plats are from four tenth-acre plats each year except for the 
years 1920 and 1921. For these two years the yields are averages of 
eight tenth-acre plats each year. 
The methods of cultivation used on each of the 10 plats in the 
experiments reported in Table 10 were as follows: 
1. Frequent cultivation; disked in both fall and spring before plowing; clean 
summer fallow. 
2. No cultivation of summer fallow after plowing; weeds hoed off before maturity; 
3 and 8. Check plats. Frequent cultivation; disked in the spring before plowing. 
clean fallow. 
4. One harrowing immediately after plowing; no further cultivation; weeds hoed 
off before maturity. 
5. Frequent cultivation; no disking before plowing; clean cultivation of fallow. 
6. Frequent cultivation; same as No. 5 except that the crop was harrowed in spring. 
7. Packed with subsurface packer after plowing and harrowed once only; weeds 
hoed off before maturity. 
9. Packed with subsurface packer and frequently cultivated; clean summer fallow. 
10. Packed with surface packer and frequently cultivated; clean summer fallow. 
TABLE 10.—Annual and average yields of Turkey winter wheat in tillage experiments 
at Moro, Oreg., during the 9-year period from 1913 to 1921, inclusive. 
[Yields of check plats, all of which were plowed on April 1, are not included in the averages.} 
Yields per acre (bushels). 
| Average. 
Method of cultivating i» ee 
fallow. | l 
1913 | 1914 1915 1916 1917 | 1918 | 1919 | 1920 | 1921 | Nine | Eight 
years, | years, 
1913 to | 1914to 
| | 1921. | 1921. 
as > = keris a | 
Plowed April 1 (early | 
spring). 
ihneatmeng Ue ss ess 23.0) 25.6.|. 23:6 | 34.3 |) 21.2 | ° 17-3") -38.3"). 25.0"). 3655)" 2a eee 
matment 2:2 2.c. 23 22.3} 26.0.) 22.1] 33.2 /-24.0] 21.0] 36.2.) 27.0) 27:7). 26. 6:5 ene 
Treatment 3 (check)-.-| 25.1 | 26.9-| 26:3 | 41.3 | 25.0| 22.3} 38.5 | 29:7] 31.3))=29:6-) 55072 
iregdpmtent 4s aaj oe | PH eat 29.3 | 24.8] 39.8 19.8) | 19,5) S82) 2707 | ~ 2bs Sais 27.2 
Treatment 52. .-...5-.- | 30.0] 32.0 | 26.4) 45.7] 25.7) 23.5.) 39.71: 32.8| 3.7 | Sooo 
Mreatment'6. -..:=22-5.5 | 23.7] 30.5 | 27.5] 37.8) 22.0] 20.31 41.2} 35.0) 32.8] 30.1} 30.9 
Meatmient 7.22... 22.08 | 27.2] 310) 95.8). 440) 147 |. 183 1 S604 (3395 |, 257 ee 28.6 
Treatment 8 (check).. -| 26.3] 283) 2759) 4d07 f 2385 1) 21a || AO tolees ena 31.7] 32.3 
Treatment 9. ....-4-.<- Zonk 280 D2|) 28.4 42 Tie 25. te|  22..8:-\- 439-2 S4.5e|) toa al: i 32.2 
Treatment. 105.2... 2-22: | 18.0" 28.07)" 2857 4923") > 2521 27-81. 38.5.4 38.3-] 35.8). 32) Desens 
if | 
Average.......:- 24.3 |-28.9 | 25.9 40. 9 |) 22232. 21.3) | sas.) lod | lope eda 30.0 
j 
Plowed May 1 (late 
spring). | 
Preatmennt Les... 2 ...0s 2 18.5 | 27.8| 27.5} 35.1 Dad 19:25) 35.3) (25238 gab.7|. -2ice | 28.7 
Treatment. 2.2.2... 20.5 | 25.0.) .22.7-4 ° 33.2)]) 23.2). D2 Seek eest|) Cons 25.9 | 26.6 
Treatment 3 (check)..:| 23.6 | 27.41] 27.0 |. 38.2.| 24.3 | 22.0'|- 37.2 | 28.3 | - 35581) 29:3 30. 0 
Treatment 4 19.8] 28:05} 25.15) (36.7 19.0| 23.5] 30.3| 27.7| 26.01 26.2 2708: 
Treatment 5... 1920°|) 27.0) |'224.75|> 38.00 | *24 572) 24TH eS0 Oe Sie Oi QOS se aend 28.7 
Treatment 6 16.0} 26.3] 25.5} 40.2 | 20.3 19-5) 1816.8: olen | 30:3" 26n8 | 28. 2 
Treatment 7 18.3 27.7.| 25:5.) 35.8 | ~10:3:]) 24:1 )\ "3055 | 3253"), 28:8.) > 25200 ees 
Treatment 8 (check)...| 21.8} 28.2] 30.0| 46.3} 25.4) 23.5] 42.5] 38.5] 36.0) 32.5 33. 8 
Hreatment 9.2. = eto 17..7_| 238.4°|- 26:48). 4298 | 2554542420) (S258) ese Sal Seo 28. 4 29.7 
Mreatment 102-2 2s2e22¢ 18.1 | 20.8] 24.6) 48.0) 25.8] 22.7) 30.7] 35.0] 31.8] 28.6 | 29.9 
A Verage 56254) 2 1S3.5F 25:8) 2552) esea | DNA DO45 te S12) es Oven |ets0s Or meen Ly 28.2 
= 1 
Re SS ee Sn ee 
era eres came: iy 
wea eb a ee 
