asmuch, however, as the walnut, pecan, etc.,
are native trees, it is probable that when these nuts are cultivated
they will be attacked by many of the insects which prey upon them in
nature. This we have found to be true to a considerable extent in the
case of the pecan. Many of the pests of hickory, for instance, are
becoming important enemies of the pecan.
We have few requests for information as to the insect enemies of the
hazelnut or filbert, practically none as to the almond. I surmise that
there is comparatively little injury to the two former crops in the
United States, and that in the case of the almond it is largely free
from insect pests. The secretary has suggested that I make reference
particularly to the insect enemies of the walnut. We have had complaints
of severe injury to walnuts in California from the codling moth and
walnut aphids. In this state and in the arid sections where walnuts are
commercially grown, the codling moth, the well-known apple pest, has
turned its attention to the walnut, and under some conditions does
serious injury. If walnuts are growing adjacent to pears, the marketing
of the crop, which occurs about the time the second brood of larvae is at
its height, deprives these insects of further food and they turn their
attention to the walnut. The walnut plant lice in California have just
been investigated by an agent of the Bureau of Entomology and we now
have a paper in press on these insects. We think it probable that
spraying will be a satisfactory remedy where the trees are not too
large.
In the East injury is confined largely to certain caterpillars infesting
the foliage, as the white-marked tussock moth, the fall webworm, a
species of _Datana_, and occasionally reports of severe injury from red
spider are received. Rather recently a good deal of interest has been
aroused in the so-called walnut curculio by reason of its attacking the
shoots and leaf petioles of the Japanese walnut. It attacks also other
species of walnut, including the English walnut and the butternut. This
pest has been well treated by Doctor Britton in his report as State
Entomologist of Connecticut for 1912.
While pecans are perhaps not of particular interest to growers of nuts
in the Northern States, yet brief reference will be made to some of the
insect enemies of the pecan. There are two excellent publications on
this subject, as indicated in the list of titles above. I should urge
all interested in n
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