1084 
Journal of Agricultural Research 
Vol. XXX, No. 11 
the case of the year-to-year changes in 
staple length, so the changes in the 
amounts of fertilizer used are of some, 
but probably small, importance in 
accounting for the variations in yield. 
If the bringing in of new lands has a 
significant effect on fertility, this too 
may be considered as a long-time o r 
trend influence. Weather as a facto r 
in yield may now be considered. 
1900 ’02 ’ 04 - ’06 ’08 ’10 ’12 ’ 14 - ’16 ’18 ’20 ’22 
INFLUENCE OF WEATHER FACTORS ON YIELD 
Fig. 1 . —Yield of cotton in Louisiana and yield estimated from weather factors, 1900-1922 
