20 
Colorado Experiment Station 
tests have been duplicated for several seasons. The results do not 
show that grazing off the first growth will stop alfalfa seed failure. 
Some seasons the first crop growth will set best with seed. In 
other seasons, the second growth seems to be more favorable. These 
varying results are attributed to varying climatic conditions. 
The effect of cultivation on seed production has also been the 
subject of investigation. Tests of different degrees of cultivation 
have been tried out on fields of alfalfa grown in rows, where a 
portion was left uncultivated, a portion cultivated lightly, and a i 
third portion cultivated deeply. So far as seed production was con- ; 
cerned, no difference could be seen whether the soil was cultivated or | 
not. Cultivation seems to aid in conserving moisture. But cultiva- j 
tion leaves a loose surface soil, which is seriously objectionable in 
an alfalfa seed field. The loose soil and gravel is likely to be picked 
up with the crop when the crop is harvested. Loose soil and gravel 
mixed with the seed is difficult to separate. It often damages the i 
alfalfa huller in thrashing. 
THE EFFECT OF SPACE OCCUPIED BY THE PLANTS ON 
SEED PRODUCTION 
It is generally conceded by alfalfa seed growers that a thin stand 
of alfalfa gives the best results in seed production. A thick stand 
A close-up view of the cement pots used to test out the effect of different applications of 
water on seed yields. 
