366 
Journal of Agricultural Research voi. xxvii no. 6 
later, however, as shown in column headed “ Percentage of rust August 
20,” is far from uniform. For the hybrid, they run i, 2, 5, 20, 3, 22, and 
1 per cent, respectively, for the same plats. When compared with the 
column giving the number of days from planting to maturity, it will be 
noted that there is a direct correlation between the dates of maturity 
and the percentages of stem rust. It will be noted further that it was 
only on the plats fertilized with sodium nitrate that there was sufficient 
delay in maturity to result in a higher percentage of stem rust. 
Table XII .—The effect of fertilizers on the date of maturity and on the percentages of 
stem rust on Marquis and the hybrid in igij on the commercial fertilizer plats on the 
Quinn farm, St. Paul, Minn. 
Plat 
No. 
Kind and amount of fertilizer « 
in pounds per acre. 
iuuuci m luty^iruixi 
planting to maturity. 
Marquis. 
Hybrid. 
fK 250. 
\ 
22 
IP <00. 
> IOO 
) 
IOI 
30 
K 250. 
102 
103 
(K 500. 
23 
N 500. 
104 
IOS 
P COO. 
fK 500. 
• 108 
31 
N 500. 
no 
fK 250.. 
24 
N 500. 
104 
P coo. .. 
fK 2 co. 
► IO8 
32 
*J V .*. 
N coo. 
in 
28 
Control. 
102 
104 
Percentage of stem rust. 
Aug. 10 (100 days 
after sowing). 
Aug. 20 (no days 
after sowing). 
Marquis. 
Hybrid. 
Marquis. 
Hybrid. 
7 
I 
7 
I 
10 
2 
IO 
2 
9 
2 
10+ 
5 + 
14 
5 
27 
20 
9 
2 
II 
3 + 
12 
4 
18 
22+ 
10 
1 
IO 
1 
a N=sodium nitrate; K=potassium chlorid; P=acid phosphate. 
The percentages of stem rust are high in four of the plats in the upper 
left-hand corner of Table XI. Unfortunately, these plats were in the 
shadow of a barn during part of the day, so the plants remained wet 
longer after dews and rains than did those in any of the other plats. 
It was clearly evident that this shading and late maturity were chiefly 
responsible for the increased percentage of rust in this part of the field. 
The fertilizers affected the general growth of these plants more than 
those on University Farm. The average height of the plants in all plats 
which received applications of sodium nitrate was 40.3 inches, while the 
average height of the plants in all other plats was 36.25 inches. These 
data, with others on weight of seed and of straw, and the ratio of seed 
tp straw, are given in Table XIII. 
