JOURNAL OF mm RESEARCH 
You. XXIII Washington, D. C., January 13, 1923 No. 2 
EFFECT OF VARIOUS INORGANIC NITROGEN COM¬ 
POUNDS, APPLIED AT DIFFERENT STAGES OF 
GROWTH, ON THE YIELD, COMPOSITION, AND QUAL¬ 
ITY OF WHEAT 1 
By JDavidson, Soil Chemist , and J. A.‘ LeClErc, formerly Chemist in Charge, 
Plant Chemical Laboratory , Bureau of Chemistry, United States 
Department of Agriculture 
INTRODUCTION 
In a series of experiments reported in 1917 and 1918 2 sodium nitrate 
was applied at different stages of growth. When the sodium nitrate 
was applied at the first stage, when the crop was about 2 inches high, 
an increase in yield was obtained. When applied at the second stage, 
at the time of heading, the yield was not affected, but a higher nitrogen 
content, both in the grain and straw, was obtained, and yellow-berry 
was practically eliminated. When applied at the third or milk stage, 
almost no effect was observed. The wheat used in those experiments 
was a soft winter wheat. The terms flinty and yellow-berry refer not 
to the typical qualities of wheat designated by them but only to the 
color of the grain. 3 
The experiment discussed in this article was undertaken with two 
objects in view. One was to repeat the previous experiments with a 
hard winter wheat in a region where the prevalence of typical yellow- 
berry fluctuates from year to year; the other was to determine the effect 
of nitrogen derived from carriers other than sodium nitrate. 
The experiment was carried out on the farm of the Claassen brothers, 
near Beatrice, Cage County, in the State of Nebraska, 4 in the summer of 
1917. 
1 Accepted for publication July 2, 1921. 
2 Davidson, J., and LeClerc, J. A. the effect of sodium nitrate applied at different stages of 
growth on the YIELD, composition, and quality of wheat. In Jour. Amer. Soc. Agron., v. 9, no. 4, 
p. 145-154, 1917; v. 10, no. 5, p. 193-198, 1918. 
3 Since this work was completed, W. F. Gericke (on the protein content of wheat. In Science, 
N. S., V. 52, p. 446-447. 1920; differences effected in the protein content of grain by appli¬ 
cations OF NITROGEN MADE AT DIFFERENT GROWING PERIODS OF PLANTS. In Soil Science, V. 14, p. 103- 
109. 1922) reported results which, with due allowance for the greenhouse conditions under which his 
experiments were carried out, are identical in their essential tendencies with the results just referred to. 
The two papers by Davidson and LeClerc, 2 which had been presented at consecutive annual meetings of 
the American Society of Agronomy before they were published, seem to have escaped Mr. Gericke’s 
notice, as he asserts (Science, loc. ciT.) that his results obtained with wheat, one of the plants studied, 
throw new light upon this protein question. 
4 The authors wish to acknowledge the valuable assistance of County Agent I,. B. Rist and of the owners 
of the farm. 
Journal of Agricultural Research, 
Washington, D. C. 
abc 
Vol. XXIII, No. 2 
Jan. 13, 1923 
Key No. E-19 
20517—23-1 
(ss) 
