April, 1922 GLP:ANINGS IN BEE CULTURE 



Pollination of Sweet Clover 



Last August the U. S. Department of Ag 



233 



riculture publislied a result of some studies 

 in pollination of sweet clover in Department 

 Bulletin No. 844. These studies were con- 

 ducted at Arlington, Va., and at Ames, Iowa, 

 in 19J6. The biennial white sweet clover 



Racemes of Hiibam clover, from which bee.s were 



excluded, at DeGraff, Ohio. A large wire-cloth 



cage was placed over the plant.s while in bloom. 



Only a few seed.s were develoised. 



(Melilotufi alha) was used chiefly in these 

 experiments, for it had previously been de- 

 termined that both Melilotus alba and M. 

 officinalis (yellow biennial) were visited by 

 the same kinds of insects and that both re- 

 quired the same methods of pollination in 

 order to set seed. There is every reason to 

 believe that the annual white sweet clover 

 (Hubam) requires the same methpds of pol- 

 lination. This makes the findings of the De- 

 partment of even greater interest just now. 

 In regard to the necessity of insect pol- 

 lination for sweet clover this bulletin says: 



The results in Table V show that an average of 

 0.37 pod to the raceme was obtained from the 

 plants protected from visitation by all insects dur- 

 ing the flowering period. As the racemes of Meli- 

 lotus alha will average appro.ximately 50 flowers 

 each, less than 1 per cent of them set seed without 

 being pollinated by insects. ***** 



On account of the ease with which the heavy 

 flow of nectar of sweet clover flowers may be ob- 

 tained many insects visit the flowers, thereby pol- 

 linating them. While the useful insect visitors of 

 flowers of red clover are limited to a few species of 

 Hymenoptera, those pollinating sweet-clover blos- 

 soms are many and belong to such orders as Coleop- 

 tera, Lepidoptera and Diptera, as well as to the 

 Hymenoptera. However, in the United States the 

 honeybee is the most important pollinator of sweet 

 clover. 



Recognizing the value of honeybees in pol- 

 linating sweet clover, the leading growers 

 of Hubam seed, last summer, had a large 

 number of colonies of bees moved into the 

 midst of their acreage of seed-producing 



Hubam. The A. I. Root Co. supplied a car- 

 load of bees to pollinate the Hubam clover 

 for the DeGraff Food Co., DeGraff, Ohio. 

 Pollination of Cotton. 

 Who would ever think there could be any 

 relation between the honeybee and the pro- 

 duction of automobile tires? Here is a state- 

 ment by Thomas H. Kearney, Bureau of 

 Plant Industry, U. S. Department of Agri- 

 culture, in The Journal of Heredity, March, 

 1921, showing the importance of the honey- 

 bee in increasing the yield of the long-staple 

 cotton, used bj^ tire manufacturers. 



There can be no doubt, in the light of these facts, 

 that thorough pollination, which results in an in- 

 creased number of seeds per boll, also increases the 

 yield of fiber. What, then, can the cotton-grower do 

 to insure effective pollination? It is, of course, not 

 in his power to increase the number of wild bees 

 and wasps which visit his cotton flowers, but often 

 honeybees also are effective pollinators. It would, 

 therefore, seem desirable to encourage the keeping 

 of bees in the vicinity of the cotton fields and to 

 watch their behavior in relation to the crop. 



The use of bees to increase the yield of 

 long-staple cotton was also advocated by 

 Rowland M. Mead in the Journal of Hered- 

 ity for October, 1918. 



More and more careful investigation is 

 revealing the value of the honeybee to agri- 

 culture. The growers of insect-pollinated 

 crops of the future will not take a chance on 

 the haphazard pollination by insects not un- 



Racenics of Hubam clover to which bees had free 

 access during bloom. These were taken from the 

 same plot of ground as those shown in cut at left 

 but were outside the cage during bloom. Note 

 they are well filled with seed pods. 



der control, but will demand that pollina- 

 tion be insured every year. Agriculture in 

 the future will, no doubt, demand that large 

 numbers of bees be kept where certain crops 

 are grown. Agriculture would demand this, 

 even though honeybees never yielded any 

 returns in honey. 



