36 BULLETIN 1421, U. S. DEPARTMENT OF AGRICULTURE 
TaBLE 15.—Variation in yield of sugar beets on general crop farms, 1919-1922 
Number of records 
Yield per acre class limits === 
3 1919 1920 1921 1922 
Short tons 
91 T0282 ee ee a a oe eee ree | eee ee A eos Sis 
WS GO QO 2 ee Eee re a ae ee eee 24 See 
1 Gta Fo it pn ae eee RI ee Sie RUN are, yess ee 5 Ui 2 
[2 tO V4 5 A cir ee Se a laa i ek ae a mee pes a ee ee 12 19 12 
OT Fe Yl Met eae see meant oe Aree aL es ieee NE CRE 2 este eu ES es ee Ne 13 23 18 
GCOS ene a as ep er ele 20 15 23 
BGO Be eS a ae eS ee 10 6 ia | Soe: 
g 8 010 (2) airs pea eam oee Loe EN het ae ee ee el Ce eee ee eee a ee 1 [al PERN oe 
5 Dc) 2 1 elec es lee ca OR Sa OAL nen Ae SR oer 8 ie ee a re eo 60 77 69 10 
TaBLeE 16.—Variation in yield of beans on general crop farms, 1919-1922 
Number of records ~ 
Yield per acre class limits 
1919 1920 1921 1922 
Pounds 
3°000!t0:3;:500. S522 sas ee oe Sn ee ae ee ee ee | rere en |e eee | ee ae 1 
2400: 60:25999 2 2 aS Ba ta ee ge | a ee | 1 5. 
AS00602! 399 ss: Be ee ea rn eee 6 Ea 5 18 
i 200 FO, LOO = aw se es kena ae oe ee eee 22 27 23 20 
GOO GOT, TOO Se aes ea eas Ba ES Se a ee 35 26 12 3 
Winder: 600. 2 .20se 6 eset Se 2 ae eee 7. 7 122 
Totahes.ts ese ee ee ea ee eee ee 70 63 53 AT 
TaBLE 17.—Variation in yield of red clover seed on general crop farms, 1919-1922 
Number of records 
Yield per acre class limits 
1919 1920 1921 1922 
Pounds 
LOOLCO:. 799 2 = SE a aa ary ae 1G) ssh ee os ee ee 
GOD GO'GOD tienes Sein ae pe EB Fe De Rat ye epee ee Ooi eon Sete t Reel ae Se econ, Ae eS 
HOO. CO R599 es Deg ae ee a Piel STAD 1 1 
AO! COA OG ir a ae re ere ae a SR eS 2 3 5 6 
BOO SOO e 2 See eee ae i i Se es 9. 10 13 10 
PMO) Ane ee ee eS Wop en ORME Guth Cane ne eM a re ioe a 13 15 23 7 
TOO CO LOG 2 SE EN ENE RAE Tes Ae Sap ops go ee a 6 11 27 6 
ni 0(6 Cy cia 0, 0 Jeeeeeane aceasta renege Ueenen erent ries oe ee 3 3 5 1 
SOME FACTORS THAT INFLUENCE CROP YIELDS 
Figure 20 shows the effect of high and low crop yields on the per- 
centage return to capital, and Tables 12 to 17 make it clear that crop 
yields may be materially increased on many of these farms. Table 18 
is designed to illustrate concretely how the yield of irrigated field 
crops may be affected (1) by the rotation of crops, (2) by the applica- 
tion of barnyard manure, and (3) by the introduction of a leguminous 
crop into the rotation, | 
RE wig ty 
(hee oS he 
