creted a scaly covering under which their eggs
for the next season's crop winter. A smothering spray like lime and
sulphur applied strong when the trees are dormant will practically
control this scale. But the young may be destroyed in summer by a
contact spray such as tobacco leaf extract or whale oil soap.

8. THE LEAF BLISTER MITE is a small, four-legged animal, so small as
hardly to be visible to the naked eye. It passes the winter in the
bud scales and as soon as these begin to open in the spring it passes
to the tender leaves which it punctures, producing light green or
reddish pimples according to the variety of apple. These later develop
into galls or blisters of a blackish or reddish brown color and
finally result in the destruction of the leaf. Trees are sometimes
practically defoliated by this pest, and this at a time when a good
foliage is most needed. Inside of the galls eggs are deposited and
when the young hatch they burrow in all directions. In October the
mites abandon the leaves to hibernate in the bud scales again. A
strong contact spray of lime sulphur when the trees are dormant
destroys the young mites while they are yet on the bud scales, which
is practically the only time when they are vulnerable.

9. APHIDES, or plant lice, are of seasonal importance. Although nearly
always present, it is only occasionally that they become so numerous
as seriously to damage mature apple trees. But they are more often
serious pests on young trees where they should be carefully watched.
Their presence is determined by the curled and distorted condition of
the terminal leaves on the under side of which the green or pinkish
lice will be found. Eggs deposited in autumn pass the winter in this
condition, hatching in the spring about the time of the beginning of
the growth of vegetation. From these winter eggs females are hatched
which bear living young, which may also bear living young and so on
for several generations until autumn, when eggs are again deposited
for the winter stage.

Fortunately weather conditions together with parasitic and predaceous
insects hold them more or less in check. Because of the difficulty of
getting at the underside of the curled leaves where these lice mostly
work they are extremely hard to control. Lime and sulphur when the
trees are dormant destroy as many of the eggs as it comes in contact
with. A tobacco extract is quite effective as a contact spray in the
growing season. The tree