GBAIN-SORGHTJM EXPERIMENTS IX OKLAHOMA. 51 
milo should be seeded about the middle of June, though possibly any 
time in June would be satisfactory. 
Sunrise kafir made the highest yields from the May 15 seeding in 
1917. 1919. and 1920. In 1918 and 1921 the June^ 1 sowing pro- 
duced the highest yields, though none of the sowings made even fair 
yields in 1918, and in 1921 the plat sown on June 1 outyielded that 
sown on May 15 by only 0.5 bushel. In the averages for three, five,. 
and six years the May 15 seeding ranks first for Sunrise kafir, with 
the June 1 seeding second. These results show that the middle of 
May is the best time to seed Sunrise kafir. with the best seeding period 
extending toward the latter part of May rather than earlier. 
Dawn kafir, for which data for only three years are available,, 
shows results similar to those of Sunrise kafir, though the average 
yields from sowings on the different dates are closer together than 
the 3-year averages for the Sunrise kafir. 
Feterita during the three years it has been grown in these experi- 
ments has made an average yield of 36.4 bushels from seedings on 
June 15 and 36.2 bushels from the May 15 seedings. Feterita has 
been a very consistent yielder during the three years it has been 
included in the date-of-seeding experiments. It must be remem- 
bered, however, that these three years have been unusually favorable 
for grain-sorghum production. 
Blackhull kaoliang made the highest yields from the June 15 seeding 
in each of the three years it was grown. 
One fact to be noted in connection with these date-of-seeding re- 
sults is that in the 5-year averages for the different dates Sunrise 
kafir has outyielded Dwarf Yellow milo from May 1 and May 15 
sowings, but Dwarf Yellow milo has averaged higher than Sunrise 
kafir when seeded on the other four dates. As mentioned before, the 
varietal plats have been seeded as near the middle of May as condi- 
tions have permitted, and the same result was obtained in the va- 
rietal experiments as from the May 15 sowing in the date-of-seeding 
experiments, i. e., when seeded on or near the middle of May Sunrise 
kafir makes a higher grain yield than Dwarf Yellow milo seeded at 
the same time. The 5-year average yields of Dwarf Yellow milo 
sown on June 1, June 15, and July 1, however, have been higher than 
the yields of Sunrise kafir sown on May 15, the best date for that 
crop. 
It should be remembered that all plats in the rate-of-seeding ex- 
periments were prepared for seeding before any of them were sown 
and that those sown at the later dates were kept free from weeds until 
seeding time. Prevention of weed growth conserved moisture and 
plant food, and results less favorable to late seeding would certainly 
have been obtained if weeds had been allowed to grow on these late- 
sown plats. Land which is not to be planted until late May or during 
June should be prepared in late April or early May and kept clean 
thereafter if the best results are to be obtained. 
These date-of-seeding experiments with several representative 
varieties of grain sorghum clearly bring out the limitations of a 
varietal experiment with several groups which respond differently to 
climatic conditions and under conditions where the possible seeding 
dates cover a relatively long period. Considering only the varietal 
experiments, one would be justified in concluding that Sunrise kafir 
is a surer and higher grain vielder than Dwarf Yellow milo. The 
