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Japanese plums, and in some varieties of European or d omesti c plums 
and prunes . Sour cherries are considered largely self -fertile, al- 
though there is some evidence of partial self-sterility. Kost peach 
varieties are self -fertile; the J. H. Hale and June Elbert a (Mikado) 
are notable exceptions, as they require cross- pol lination . Sterility 
in plums, cherries, and perhaps other fruits may sometimes be due to 
deformed or imperfect pistils. Some grape varieties must be cross- 
pollinated in order to be fruitful. 
There is every conceivable degree of self-sterility, from one 
extreme where no fruit sets without cross-pollination to that where 
it is so slight as not to be a serious factor in fruit production. 
The opinion is commonly held that even the varieties considered to 
be self-fertile in a high degree will set a better crop of fruit if 
cross-pollination occurs . With self-sterility prevailing to so large 
an extent in common fruit varieties, the relation of weather condition s 
favorable to the greatest activity of honeybees becomes readily appar- 
ent, since it is on them that the fruit grower must depend very large - 
ly for the cross-pollination of his fruits . 
When self-sterile varieties are planted and there are no other 
trees of different varieties of the same kind growing near enough to 
insure the passing of bees from one to the other, it will be found 
that trees blossom but do not set fruit . 
When the tree to be cross-pollinated is in bloom secure some 
blossoming branches from a tree of another variety of the same kind 
of fruit and place them in a pail or other water container in the top 
of the tree. The bees, visiting the trees, will also visit the blossoms 
on the branches and will thereby transfer the pollen as they revisit 
the blossoms on the tree . 
Mumeek, A. E. 
1930. Fruit pollination. Mo. Agr. Expt. Sta. Bui. 283, 12 pp. 
p. It With proper care bees winter over in large numbers and 
are very active in the spring. They are especially well adapted to 
carry pollen. Their bodies and legs are covered with hairs to which 
the pollen grains adhere in large numbers. Moreover, the h o neybee 
visits only one kind of flower, like the apple or the peach , at a 
time . Thus they are very effective agents in cross-pollination . 
p. 9: It has been demonstrated in many orchards in a convincing 
way that bees are of great value for the pollination of apples . 
sour cherries, and other fruits . If the orchardist does not keep his 
own bees and there are none in the neighborhood, then most certainly 
it will pay to secure several hives. 
S^TE PLANT BOAK* 
