we BULLETIN 836, U. S. DEPARTMENT OF AGRICULTURE. 
C. I. Nos. 559, 564, 595, and 597 were obtained from different. seed 
companies and grown in 8-rod rows at the Woodward Field Station 
for two or three years before being included in the varietal experi- 
ment. 
The agronomic data for Dwarf broom corn are shown in Table 
VII, while the annual and average acre yields are shown in Table 
VIII, where comparisons with the Standard and Acme varieties are 
made. 
The row space per plant in the different lots does not vary more 
than about an inch in any one year, while the average row space for 
all lots in the same year ranges from 6.3 inches in 1915 to 8.6 inches in 
1916. From this standpoint the Dwarf varieties are directly com- 
parable with the other varieties used in the experiment. | 
The total growing period of the three lots grown during the entire 
5-year period ranged from 84 days in 1918 to 114 days in 1917, with 
an average of 94 days for the period. This is the same average 
period as for the Acme, but 9 days less than was required by the 
Standard, which was 103 days in the same period. The average 
proportion of suckers in these same three lots is 15.5 per cent, which 
is 8.5 per cent greater than for Acme and about three times as high 
as for the Standard, C. I. No. 556. 
In height C. I. No. 442 is consistently lower than any of the other 
lots. Its height ranged from 2.3 feet in 1918 to 4.3 feet in 1915. 
While the other two lots are of practically the same height in most 
years, they show a difference of 6 inches in 1917, each reaching its 
maximum of 5 and 5.5 feet, respectively, in that year. The new 
lots added in 1917 compare favorably in height with the two just 
mentioned. 
The average yield of good brush by the three lots grown during 
the entire 5-year period ranged from 240 pounds in 1918 to 615 
pounds in 1915. The average total yield produced in these same 
two years was 278 and 752 pounds, respectively. The yield of good 
brush was 85.8 per cent and 82.2 per cent of the total yield. The 
higher percentage of good brush was produced in 1918, when the 
lowest total yield was made, and the lower percentage in 1915, when 
the highest total yield was made. This tends to show that the per- 
centage of good brush does not depend so much upon the quantity 
of brush produced as on the conditions under which it is grown. 
Growth that is too rapid or too slow during the fruiting period has a 
bad effect on quality. The former makes coarse, burly, or twisted 
brush and crooked heads, while the latter causes the brush to be 
short and spiky. The greatest average length of good brush, 21.7 
inches, was produced in 1915, and the shortest, 15.5 inches, in 1917. 
In the former year the length of the poor brush was the same as the 
good, but the crop made a rapid growth and developed some coarse, 
——i ee ee ee le 
* r] ls 
co -40d Viper 
