RED-CLOVEK SEED PRODUCTION. 27 



cent. This small yield of seed may be accounted for by the occa- 

 sional access of bees to these heads for a very short time, on account 

 of rains or grasshoppers mutilating the tarlatan which was used to 

 cover the heads. 



The bumblebee is an efficient cross-pollinator of red clover. 

 Bumblebees are able to pollinate from 30 to 35 flowers a minute. 



The honeybee proved to be as efficient a cross-pollinator of red 

 clover as the bumblebee in 1911. When the precipitation was con- 

 siderably below normal in June, July, and August, 1911, and but 

 few nectar-producing plants were to be found, honeybees collected 

 large quantities of pollen from red clover. In order to collect pollen 

 they must spring the keels of the flowers. In doing this they cross- 

 pollinate the flowers. 



A clover cross-pollinizing machine which was offered for sale on 

 the market did not prove to be an efficient cross-pollinator of red 

 clover. 



The various types of hand-operated brushes which were used did 

 not prove efficient as cross-pollinators of red clover. In nearly all 

 cases where these brushes were used the seed yield was decreased 

 instead of increased. This was undoubtedly due to the bristles of 

 the brushes injuring the flowers, since the average seed yield of the 

 plats which received three treatments with the brushes was lower 

 than that of the plats which received but one treatment. 



