The insects most commonly attacking the apple are the codlin-moth,
tent-caterpillar, canker-worm and borer. The codlin-moth lays its eggs
on the fruit about the time of the falling of the blossoms, and the
larvae when hatched eat into the young fruit and cause
wormy apples and pears. Owing to these facts, it is too late to reach
the trouble by spraying after the calyx closes on the growing fruit.
Keep close watch and spray immediately upon the fall of the blossoms,
and repeat the spraying a week or so (not more than two) later. For
spray use Paris green at the rate of 1 lb., or arsenate of lead (paste
or powder, less of the latter: see accompanying directions) at the rate
of 4 lbs. to 100 gallons of water, being careful to have a thorough
mixture. During July, tie strips of burlap or old bags around the
trunks, and every week or so destroy all caterpillars caught in these
traps. The tent-caterpillar may be destroyed while in the egg state, as
these are plainly visible around the smaller twigs in circular,
brownish masses. (See illustration.) Upon hatching, also, the nests are
obtrusively visible and may be wiped out with a swab of old bag, or
burned with a kerosene torch. Be sure to apply this treatment before
the caterpillar begins to leave the nest. The treatment recommended for
codlin-moths is also effective for the tent-caterpillar.
The canker-worm is another leaf-feeding enemy, and can be taken care of
by the Paris green or arsenate spray.
The railroad-worm, a small white maggot which eats a small path in all
directions through the ripening fruit, cannot be reached by spraying,
as he starts life inside the fruit; but where good clean tillage is
practiced and no fallen fruit is left to lie and decay under the trees,
he is not apt to give much trouble.
The borer's presence is indicated by the dead, withered appearance of
the bark, beneath which he is at work, and also by small amounts of
sawdust where he entered. Dig him out with a sharp pocket-knife, or
kill him inside with a piece of wire.
The most troublesome disease of the apple, especially in wet seasons,
is the apple-scab, which disfigures the fruit, both in size and in
appearance, as it causes blotches and distortions. Spray with Bordeaux
mixture, 5-5-50, or 3-3-50 (see formulas below) three times: just
before the blossoms open, just as they fall, and ten days to two weeks
after they fall. The second spraying is considered the most important.
The San Jose scale is of course really an insect, though in appearance
it seems a disease. It is much more injurious than the untrained fruit
grower would suppose, because indirectly so. It is very tiny, being
round in outline, with a raised center, and only the size of a small
pinhead. Where it has once obtained a good hold it multiplies very
rapidly, makes a scaly formation or crust on the branches, and causes
small red-edged spots on the fruit (see illustration). For trees once
infested, spray thoroughly both in fall, after the leaves drop, and
again in spring, _before_ growth begins. Use lime-sulphur wash, or
miscible oil, one part to ten of water, thoroughly mixed.
Previous: PRUNING, SPRAYING, HARVESTING
Next: CHERRY ENEMIES
|ADD TO EBOOK