1 BULLETIN. 836, U. S. DEPARTMENT OF AGRICULTURE. 
pared for immediate use. The pressure of other work prevented 
breaking new sod in time for the 1915 crop, so the same land was 
used as in 1914. Later in the season more sod was broken. This sod 
land was fallowed and used for the 1916 crop. In 1917 the varietal 
experiment followed the same crop, and the other experiments fol- 
lowed cowpeas. In 1918 the varietal experiment followed cotton, 
and the other experiments followed broom corn. 
METHOD OF SEEDING. 
A 2-row combined corn and cotton drill fitted with sorghum plates 
was used for sowing the crop from 1914 to 1916, inclusive. Since 
then a 2-row drill fitted with a special plate, which is thinner than 
the ordinary sorghum plate, has been used. This plate contains 36 
holes, each three-sixteenths of an inch in diameter. The feed was 
run on high gear, which drops at intervals of about 3 inches. It 
was desired to have only one kernel dropped at a time, and the 
above-described plate was designed to accomplish that end; but in 
many cases two and oczasionally three kernels were dropped, be- 
cause the kernels vary in size. 
Broom-corn seed usually remains in¢iosed in the glumes or hulls, 
but some seed is dehulied by the thrasher. Seeds free from glumes 
will pass through a much smaller hole than the seed remaining in 
the hulls. This makes a drop of a single kernel each time impossible 
where the dehulled seeds are mixed and the holes in the plates are 
large enough to drop seeds covered with a hull. 
Seeding was done at a rate heavy enough to insure a thick stand 
under normal conditions, with the idea of obtaining a stand suffi- 
cient for these experiments if the conditions were unfavorable. 
When the plants were from 6 to 10 inches high the plats were 
thinned by hand to the stands desired in the different experiments. 
DATES WHEN THE CROPS WERE SOWN. 
The dates on which the crops in the varietal, rate-of-seeding, and 
spacing experiments were sown each year are as follows: In 1914, 
all three experiments were sown on May 14. In 1915 the varietal 
and the rate-of-seeding experiments were sown on May 25 and the 
spacing experiment on the following day. In 1916 the spacing ex- 
periment was sown on May 19 and the other two on May 22. In 
1917 the spacing experiment was sown on May 18 and the others 
on May 24. In 1918 the varietal and rate-of-seeding experiments 
were sown on May 27 and the spacing experiment on June 3. 
METHODS OF COLLECTING DATA. 
The data on plant and stalk spaces and on the occurrence of 
suckers and heads were obtained by actual counts of the plants, 
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