122 The Colorado Experiment Station 
EXPERIMENTS OF I9II. 
In 1910 we added Chile-saltpetre up to 1,250 pounds per acre, 
making the last, the fifth application of 250 pounds on 27 July. It 
seems to have been established that the beet plant appropriates about 
three-fourths of the total amount of nitrogen used during the season 
in June and July and consequently only smaller amounts after 1 Aug. 
Our results in 1910 indicated that 1,000 pounds per acre, the fourth 
portion of 250 pounds applied 22 June, produced the maximum 
effect. This is at a time when the beet is appropriating nitrogen 
most actively. Our examination of soil samples shows the presence 
of large amounts of nitric nitrogen in our cultivated fields, especially 
in fallow spots later in the season. If this nitric nitrogen in the soil 
be, as I believe it is, primarily due to fixation there is no reason why 
the supply should not occur later or perhaps continue throughout 
the season. For this reason, and further to study the effect of large 
amounts of nitrates upon the ash content of the beet and particularly 
upon the amount of phosphoric acid appropriated, further experi¬ 
ments were instituted. In these we made our first application of 
nitrates at the rate of 250 pounds per acre 4 Aug. 1911, and three 
subsequent ones at the rate of 125 pounds per acre at intervals of 14 
days, making the last application 28 Sept. The beets were already 
well developed when these experiments were begun, the tops were 
exceedingly heavy and very dark green in color. The varieties used 
were Wohanka Erntereichste and Zuckerreichste. One-tenth acre 
was used in each case and check plots of like size. All plots were 
irrigated five days after the first application of nitre. There were 
light showers on 1 and 2 September, about 0.14 inch of rain. On 
11 September the plots were again irrigated. Cultivation was out 
of the question owing to the heavy, very brittle foliage. The first 
samples were taken from the check plots 8 Aug. All samples taken 
from these plots consisted of at least 18 beets each, of which a com¬ 
posite sample was made. The second set of samples was taken 18 
Aug. and every 14 days thereafter till the beets were harvested 8 
Nov., the latest possible date, because there was great danger of 
their being frozen in the ground. The effects of the nitre were very 
evident in less than a fortnight in the increased growth and deepened 
color of the foliage. This difference continued to become more evi¬ 
dent till about 10 Oct. when the check plots showed unmistakable 
evidences of ripening while the treated plots were still in the full 
vigor of their growth. During the night between 20 and 21 Oct. 
the temperature fell to 13.6° F. and the tops were of no further use 
to us. The beets, however, were effectively protected by the heavy 
foliage and the fact that they had grown well below the surface of 
the ground. 
Samples of these beets were photographed 15 Aug. to show the 
