USING BEES FOR CROSS-POLLINATION 405 



very common, every fruit grower should arrange to have 

 colonies of bees evenly distributed throughout the orchard at 

 blossoming time. 



It has been shown by different investigators that pollen of 

 several of our tree fruits is carried only short distances by the 

 wind and that agency cannot be relied upon to effect satis- 

 factory cross-pollination. No doubt wind, especially by shak- 



FiG. 160. Left, a honey bee with pollen grains on its body as a result of 

 visiting blossoms; right, a bumble bee, showing pollen grains. (Mich. 

 Special Bui. 188, Photos by Cornelius Clarke, Grinnell, Iowa.) 



ing and jarring the limbs, aids in distributing the pollen from 

 the anthers to the pistils of the same blossoms, however, and 

 thus helps to cause better sets on self-fruitful varieties, espe- 

 cially in peaches and sour cherries. 



Insects are the main agencies in effecting cross-pollination 

 between varieties. In flying from blossom to blossom their 

 bodies become covered with different varieties of pollen, and 

 this is left on the different stigmas as they crowd down into 

 the blossom to secure the nectar. Honey bees, because of their 



