Feb. 9, 1924 
Effect of Fertilizers on Stem Rust of Wheat 
361 
Tab LB VIII. —Summarized data on the effect of barnyard manure on the percentage of 
stem rust on Haynes Bluestem and on the hybrid in the plats treated with commercial 
plus natural fertilizer in igi6 on University Farm, St. Paul, Minn. 
Plats. 
Number 
of plats 
included. 
Average percentage 
of rust. 
Range of rust 
percentage. 
Bluestem. 
Hybrid. 
Bluestem. 
Hybrid. 
All... 
9 
58.5 
40.2 
55-63 
34-43 
Control. 
I 
55 
38 
55 
38 
Receiving 10 tons manure per acre. 
4 
60.5 
41-5 
58-63 
40-43 
Receiving 25 tons manure per acre. 
4 
60 
4I.2 
58-63 
40-43 
EXPERIMENTS WITH COMMERCIAL, FERTILIZERS IN 1917 
General Plan 
In 1917, experiments were made on three different farms. The 
general plan was the same for each, but there were some minor variations. 
The series were as follows : 
First series, University Farm.— The plats were laid out in exactly 
the same place as in the previous two years. The soil therefore was 
the heavy Hempstead clay loam. 
Second series, Quinn Farm. —The plats were laid out on light 
Hempstead clay loam. They were about 1 % miles from those in the 
first series. The soil on the Quinn farm, while of the same general 
type as that on University farm, wa£ much lighter, contained more 
sand and was not so well supplied with nitrogen. 
Third series, Anoka. —The plats were laid out on Merrimac loamy 
sand near Anoka. The soil was very light and deficient in nitrogen. 
Results op First Series—University Farm 
The experiments on University Farm were made on the same plats 
used in the previous two years; but acid phosphate and potassium were 
not applied, because it was desired to ascertain whether there would be 
any residual effect of these fertilizers on the plants themselves and on 
their resistance to stem rust. Sodium nitrate was applied as usual, 
as the residual effect is negligible. On April 28 one-half of each plat 
was sown to Marquis, C. I. 3641, which is very susceptible to stem rust 
in Minnesota, and the other half was sown to the same hybrid which 
was used in 1916. 
The weather conditions in 1917 were quite different from those in 1916. 
The spring of 1916 was wet and cold, but soon after the plants headed 
it became very hot and dry. In 1917, the growing conditions generally 
were favorable for wheat. This is indicated clearly by the fact that 
there was practically no premature ripening and the yields were good 
in practically all of the plats. Stem rust did very little damage through¬ 
out the hard red spring wheat region and the yield of wheat was fairly 
satisfactory, except in North Dakota where drought reduced it. The 
average yield in Minnesota was 17.5 bushels per acre, in North Dakota 
8 bushels per acre, and in South Dakota 14 bushels per acre (33). 
The plan of the experiment and the results obtained, including the 
percentages of stem-rust infection on both varieties in each plat, are 
74025—24 - 3 
