SPRING WHEAT ON THE NORTHERN GREAT PLAINS. 17 
The acre yields for the five years, 1907 to 1911, inclusive, for four 
varieties grown in that period show that the Kubanka (C. I. No. 
1440) averaged 22.4 bushels, outyielding two commercial strains of 
common wheat, Rysting Fife and Crossbred Bluestem, by 2.1 bushels 
and 3.4 bushels, respectively. During those years the Ghirka Spring 
variety- (C. I. No. 1517) showed unusual promise as a drought- 
resistant common wheat, outyielding even the Kubanka by 0.2 bushel. 
The Marquis variety has been grown in 1913 and since. In the 7- 
year period, from 1913 to 1919, inclusive, durum varieties generally 
yielded more and other common varieties less than the Marquis. 
In the full 7-year period, the Marquis has averaged 17 bushels per 
acre. Monad durum wheat has produced the highest yield, averaging 
23.1 bushels, followed by Kubanka No. 8 (C. I. No. 4063) with an 
average yield of 22.1 bushels, and Kubanka (C. I. No. 1440) with a 
yield of 20.6 bushels. These yields are ail significantly larger than 
that of the Marquis variety. During the same period the commercial 
common wheats, Haynes Bluestem and Preston, produced yields 
significantly lower than the Marquis, averaging 12.9 and 14.6 bushels, 
respectively. The other common wheats yielded less than the Mar- 
quis by 1.9 to 3.5 bushels. 
In shorter periods the Ghirka Spring and four pure-line selections 
from it consistently yielded less than the Marquis and were discon- 
tinued in 1919. Among the rust-resistant varieties, the D-5 yielded 
on the average slightly less than the Monad in the four years the 
former was grown and about the same as Acme during the three 
years the Acme was grown, but 2.7 bushels more than Mindum in a 
2-year period. Two selections from Kubanka (C. I. No. 1440), Nos. 
58- and 98, also selected for rust resistance, have yielded fairly well 
during the last two years. Kota, a rust-resistant common wheat in 
the Preston group, produced the highest yield of all wheats in 1919. 
RESULTS AT MANDAN, N. DAK. 
The Northern Great Plains Field Station of the Office of Dry-Land 
Agriculture of the United States Department of Agriculture, at 
Mandan, N. Dak., is located near the Missouri River on upland black 
sandy loam soil at an altitude of 1,750 feet. The normal annual 
precipitation is 17.41 inches. 8 The varietal experiments with 
wheat, conducted cooperatively between the Office of Dry-Land 
Agriculture and the Office of Cereal Investigations, were started in 
1916. The yields obtained during the past four years are presented 
in Table V. 
Of the six varieties grown for four years the Marquis ranks first, 
with an average acre yield of 17.1 bushels. The durum varieties, 
s Records taken at Bismarck, 6 miles distant, during part of the period. 
184125°— 20— Bull. 878 3 
