SORGHUM EXPERIMENTS OX THE GREAT PLAIN-. 65 
Data showing how the date of seeding affects the yields of fodder 
and grain, the height of plants, and the length of time required for 
sorghums to mature are given in Table 17. 
The yield data in this table favor relatively early seeding of Sumac; 
any time between April 15 and May 15 is good, but preferably 
about May 1. Short-season varieties like Red Amber may be 
seeded at any time from April 15 to June 15, but June 1 is perhaps 
the optimum date. From a practical standpoint, however, the forage 
yields of Red Amber are so inferior to those of Sumac that the growing 
of Red Amber is scarcely justified except for late seeding or under 
conditions where the yield is entirely secondary to quick maturity. 
EXPERIMENTS AT WOODWARD, OKLA. 
The date-of-seeding experiments at Woodward. Okla.. were con- 
ducted with Sumac and Red Amber sorgo for the years 1917 to 
1921 under rather favorable climatic conditions and without material 
insect injury. Unreplicated 0.06-acre or 0.08-acre plats we^e used 
throughout the experiment. The preceding crop on the land in 
1917 and 1920 was cowpeas, and for the other three years sorghum. 
Uniform stands were obtained throughout the experiments. In 
1917 the Red Amber plats were left just as they came up, while the 
Sumac plats were thinned to 4 inches of row space per plant. In 
the other years all plats were thinned to approximately 6 inches row 
space. 
Drought was an important factor in 1917 during July and again 
in October. The July drought so checked the seedings made on 
April 15 and May 1 that the Red Amber plats of these two dates 
dried up prematurely and were harvested. Stimulated by the 6.65 
inches of rainfall during August these two plats produced a fair 
second growth, that did not ripen; and all other plats of both varieties, 
especially Sumac, developed satisfactory forage yields, the harvest 
having been delayed until the first frost on October 12. The rain- 
fall during the 1918 season was the most poorly distributed, as the 
drought began in July and continued in some degree the rest of the 
season. Two cuttings were obtained from the Red Amber seeded 
on April 15, both cuttings maturing a light crop of seed. Both 
varieties matured fair crops on all dates of seeding in 1919. though 
the rainfall was low. because the rain was effectively distributed 
and the first frost did not come until October 2S. The rainfall for 
1920 was sufficient to produce the highest forage yields obtained in 
the five years. A drought period during late July and early August, 
however, reduced the seed yields of the May seedings of Sumac. 
The rainfall of 1921 was ample except for about the same period 
as in 1920, when drought materially decreased the forage yield-. 
The effect of different dates of seeding on the yields of forage and 
grain and the average length of the growing season are shown in 
Table 17. 
The average yields differ but little for the first five dates of Sumac 
and for all the seedings of Red Amber. Inspection of the data on 
length of season shows clearly, however, how much slower the early 
seedings, especially of Sumac, were in developing. The June 1 
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