TESTS OP CORN" VARIETIES ON THE GREAT PLAINS. 9 
Since small differences are of little importance in judging the 
value of different varieties, the varieties are divided into three 
classes according to yield for each year and the result is shown in the 
last three columns of the summary tables. Class 1 is made up of 
varieties yielding above the average; class 2 of varieties of about 
average yield, and class 3 of varieties yielding less than the average. 
In calculating yields, 70 pounds of dry ears are used for 1 bushel. 
TESTS AT HUNTLEY. 
The tests at Huntley, Mont., have been made under irrigation. 
Three years' results are available. In 1912 the test contained 6 
varieties; in 1913, 7 varieties; and in 1914, 11 varieties. Each 
variety unit was composed of two rows; in 1912 and 1913 these rows 
were 132 feet long and 3| feet apart, making an area of about one- 
forty-seventh acre per plat; in 1914 the rows were 170 feet long and 
3f feet apart, making the plats one thirty-fifth acre in area. 
In 1913 and 1914 the variety plats were alternated with check 
plats planted to a common variety, and the series was repeated three 
times. In 1913 the check plats were planted to Minnesota 13, and 
in 1914 to Northwestern Dent. The seed was drilled in the rows, and 
the plants later thinned to one' about every 18 inches. The yield in 
pounds of ears for each variety and check plat and the total yield of 
each variety are shown in Table II. Check plats are totaled in 
groups of threes, to correspond with the total yields of varieties. In 
1913 there were large differences in yields of replicate plats of the 
same variety and between the yields of check plats. The test for 
that year has little value except as the results corroborate those of 
other years in indicating good varieties. In 1914 the differences 
were smaller between replicate plat yields and the results were more 
reliable. 
The yields in bushels per acre, the increase of the variety over 
adjacent checks, and the rank and class of each variety according to 
yield are shown in the summary of Table II. For 1912 the varieties 
are ranked according to actual yield. For 1913 and 1914 the varieties 
are ranked according to the amount by which the average yield of 
the three plats of each variety exceeds the average yield of the six 
check plats adjacent to them. The varieties which have yielded 
relatively high in all tests at Huntley are Northwestern Dent and 
U. S. Selection 133. 
6827°— Bull. 307—15 2 
