534 
Journal of Agricultural Research 
Vol. XXIII, No. 7 
FI,OUR YIELD AND PROTEIN IN WHEAT 
The question of relation between flour yield and protein in the wheat 
is of concern especially to the miller. 
Table VII .—Correlation between flour yield and protein in Minnesota spring wheats of 
commercial varieties 
Table VIII .—Correlation coejflcients for protein in the wheat and yield of flour 
Kind of wheat. 
Number of 
samples. 
Coefficient of correla¬ 
tion. 
Commercial varieties: 
North Dakota spring wheats. 
Minnesota spring wheats. 
99 
—0. 2i67±o. 0646 
202 
.17891k .0459 
Montana spring wheats. 
34 
• 375 i± -0994 
Ohio winter wheats. 
29 
—. 2062 ± .1199 
Montana winter wheats. 
9 i 
. 0884 dz . 0702 
Minnesota winter wheats. 
Pure strains: 
43 
*3 2 3 8 ± .0921 
North Dakota spring wheats. 
Minnesota spring wheats. 
56 
—.0942± .0893 
48 
. i255± .0958 
Wisconsin winter wheats. 
22 
. 0601± . 1433 
For the nine groups of data six coefficients are positive in signs and 
three negative. The correlations for the Ohio winter wheats, Montana 
winter wheats, North Dakota spring wheats, pure strains, Minnesota 
spring wheats, pure strains, and Wisconsin pure strains of winter wheats 
are not significant, since the value of the respective coefficients is less than 
three times their probable error. The remaining four coefficients indi¬ 
cate only a very slight correlation. Of these three are positive in sign 
and one is negative. The highest correlation, that for the Montana 
