354 
Journal of Agricultural Research 
Vol. XXVII, No. 6 
binations with commercial fertilizers. The commercial fertilizers used 
were sodium nitrate, acid phosphate, and potassium chlorid. The soil 
was of the same type as that on which the experiments with commercial 
fertilizers alone were made. The plats which previously had grown 
cabbage and clover were contiguous to each other, while those on the 
alfalfa soil were a few rods distant. 
The methods used in laying out the plats and applying the fertilizers 
were similar to those employed in the experiments with commercial 
fertilizers. The plats were i square rod in area and separated from 
each other by 3-foot alleys. 
The commercial fertilizers were applied as indicated under the dis¬ 
cussion of general methods. 
Three series of plats were used. The soil in one series had grown 
cabbage the previous year, that in another had been in clover for several 
years, and that in the third had been in alfalfa for a like period. The 
ground was plowed, disked, and harrowed thoroughly before the seed 
was sown. Well-rotted barnyard manure, at the rate of 50 tons per 
acre, was applied to one plat in each series; 50 tons of manure, plus 500 
pounds of sodium nitrate, per acre to one plat; 50 tons of manure, plus 
1,000 pounds of acid phosphate, per acre to one plat; and 50 tons of 
manure, plus 1,000 pounds of potassium chlorid, per acre to one plat. 
The control plats received neither manure nor commercial fertilizers. 
One-half of each plat was sown to Haynes Bluestem wheat, the other 
half to a hybrid (No. 4 X 942.10) originated in the Minnesota rust nursery. 
This hybrid was a cross between a durum (Kubanka, C. I. 2094) and 
Haynes Bluestem. It was a fixed type and averaged 30 per cent of 
rust in the Minnesota rust nursery in the five years from 1912 to 1917. 
The disposition of the plats and the kind of soil and fertilizers used 
are shown in Table V. This table also gives the percentages of stem- 
rust infection for both varieties of wheat and the total number of days 
between the time Haynes Bluestem was sown and the time it ripened. 
The stem-rust epidemic was assured by spraying with a suspension of 
spores such as had been used in the commercial fertilizer plats. 
On July 1 the stand in the control plats on the alfalfa and clover soils 
was heavier than that in the control plat on the cabbage soil. The plants 
in all of the manured plats also were quite succulent and dark green in 
color. The commercial fertilizers apparently had influenced the character 
of growth but little up to this time. 
