- 18 - 
this carrier the load of pollen is transported to the hive. 
However, all bees are not of equal value as pollinizers as some 
of them do not visit all types of flowers. The honeybee and the 
bumblebee, however, visit almost all flowers with little restriction 
except that they evidently confine themselves to a single species 
on any one trip. 
We have many native species of bees such as bumblebees, car- 
penter bee, leaf cutters and others, but only in rare instances are 
any of these active during the early spring and then only in very 
restricted numbers. 
The bumblebee is one of the earliest of the native bees to 
feed in the spring, but the entire colony, except the queen, nerishes 
during the winter. 
In the spring the whole responsibility of rebuilding the 
colony devolves upon the queen. She lays and incubates the eggs, 
seven to sixteen in number , feeds the newly hatched larvae and only 
after the first brood matures can she give her strength entirely to 
brood rearing. By fall the colony may have grown to a size of 
from one to five hundred individuals. Certain of the mining bees, 
Halictus. which nest in certain cliffs, have one or two generations 
a year. The spring generation consists of hibernating, fertilized 
females which give rise to a summer generation. The leaf-cutting 
bee, Megachile spp., apparently has but one generation a year and 
includes but a small number of individuals . The carpenter-bee, 
Ceratina dupla, has two broods a year which are very restricted in 
numbers • 
These examples are typical of the life history of our common 
native species of bees that have from one to five or six brood cycles 
annually, while the number of individuals range from a score to a few 
hundred . Comparing this with the honeybee's record of from twelve to 
fifteen brood cycles a year, all the descendants of a single queen . 
which may reach a hundred thousand bees annually, or more, we realize 
the wonderful reproductive powers of this insect. It should also be 
noted that instead of the death of all the workers, the winter's mor- 
tality among honey bees is usually very slight. From five hundred to 
sixty thousand may be present in a single colony at the close of winter 
and two or more brood cycles may be reared in the spring before many 
of the fruit trees bloom. 
Fruit Crops 
Gould, H. P. 
1939. Why fruit trees fail to bear. U. S. Cept. Agr. Leaflet 172, 
5 PP. 
pp. 3-4: Self -sterility is very common. It occurs in many 
varieties of apples , most varieties of pears, probably in all varieties 
of sweet cherries , in most if not all varieties of the native and 
