SWEET-CLOVER SEED. 
25 
of the ones labeled when the flowers at their bases were just ready to 
open was largely due to the dropping of the flowers on the older 
'racemes before the experiment was begun. < 
It will be seen that the production of mature pods on the plant 
not watered was much greater on the racemes that were labeled 
before the flowers opened than on the older racemes. This difference 
is undoubtedly due to the precipitation which fell on the sixth and 
tenth days of the experiment. It is believed that the yield of 15.23 
pods to the raceme on the ones labeled when the pods were 9 to 12 
days old is representative of the production of pods per raceme pre- 
vious to the precipitation and that the other racemes on this plant 
would have yielded proportionately if conditions had remained the 
same. 
In the early spring of 1916, Melilotus alba was planted in several 
large pots in the greenhouse of the Department of Agriculture at 
Washington, D. C. These pots were placed outside the greenhouse 
in the late spring, where they remained until the following January, 
when they were taken into the greenhouse. The plants grew rapidly 
and began to flower during the latter part of April, 1917. At this 
time two pots were placed in a large cage made of screen having 20 
meshes to the linear inch. One pot was submerged in a tub of water, 
so that the soil was saturated at all times, while the plant in the other 
pot was given only sufficient water to keep it from wilting. The 
pods on a few racemes were self -pollinated and the results obtained 
are given in Table IX. 
Table IX. — Effect of moisture on the seed production of Melilotus alba at Washington, 
D. C, in 1917. 
Soil treatment. 
Total number of— 
Flowers that ma- 
tured (per cent). 
Racemes. 
Flowers. 
Pods 
formed. 
Total. 
Increase. 
12 
17 
227 
425 
65 
234 
28.63 
55.05 
26.22 
The results of this experiment compare favorably with those ob- 
tained under field conditions at Ames in 1916. 
