re difficult to separate
from the husks.

[11] ~Laspeyresia caryana~ (Fitch).

Extensive experimentation in the control of this insect has been carried
out without much success. No effective insecticide treatment can be
recommended for its control.

~Walnut husk maggot.~ The adult of the walnut husk maggot[12] is a fly
(Fig. 3); it is related to other injurious fruit flies such as the apple
maggot, Mediterranean fruit fly, and the oriental fruit fly, which has
recently been found in Hawaii. Adults emerge from the soil and fly to
the trees in midsummer. Egg laying follows in 1 to 3 weeks, the eggs
being deposited on the husks of several kinds of nuts. The maggots feed
within the husks. Not only is the quality of infested nuts lowered, but,
in addition, the husks are more difficult to remove. A closely related
species is particularly damaging to the Persian or English walnut in
California.

[12] ~Rhagoletis suavis~ Loew.

Lead arsenate, 2 to 4 pounds per 100 gallons of water, in combination
with an equal quantity of hydrated lime is quite effective in destroying
the adults of the walnut husk maggot when applied at the time they are
present.

~Stinkbugs and leaf-footed bugs.~ There are a number of stinkbugs and
leaf-footed bugs (Fig. 4), in addition to the species mentioned,[13][14]
which are responsible for important injuries to pecans, filberts, and
other nuts. These insects puncture the immature nuts with their beaks.
The punctured areas become spongy, somewhat dark in color, and are
bitter to the taste; on pecan the typical injury is referred to as black
pit and kernel spot.

[13] ~Nezara vizidula~ (L.).

[14] ~Leptoglossus phyllopus~ (L.).

Crops of favorable host plants such as cowpeas and soybeans should not
be planted in or adjacent to nut orchards subject to attack by these
sucking bugs. In general, orchard sanitation should be practiced.

[Illustration: Fig. 6.--Galls produced by the pecan phylloxera.]

[Illustration: Fig. 7.--Injury to young pecan tree by the fall webworm.]

[Illustration: Fig. 8.--Larvae of the walnut caterpillar.]

[Illustration: Fig. 9.--Caterpillar of the hickory tussock moth.]

[Illustration: Fig. 10.--Rose chafer beetles on chestnut blossoms.]

Insects Attacking the Foliage

~Black pecan aphid.~ Pecan trees at times suffer sufficient damage from
the black pecan aphid[15] to cause considerable defoliation (Fig. 5)
during the latter part of the season. The injury to fol