and plants.
Theoretically speaking, one would not care to risk the expenditure of
much time or money in propagating a plant in a region that was destitute
of insects that might attack that plant. The absence of such insects
would possibly indicate a lack of natural conditions favoring the growth
of the plant in question. Thus the presence in any locality of insects
that feed on nuts may mean that nuts thrive naturally in that locality
and that insects are there because of the abundance of a favorite food.
May I hasten to add, however, that this fact should not lead to an
under-estimation of the possibilities of insect destructiveness, nor
encourage lax methods in dealing with injurious species. In the
beginning of any nut-growing enterprise we should anticipate the coming
of insect pests and be ready to meet them. The planting of pure stands
of native nut trees sets up a condition under which insects coming from
the forest may increase more safely and rapidly than under the more
hazardous environment of a scattered forest growth. This applies to
cultivated plants generally. It is true of an orange grove, a cornfield
or a potato patch. The mass planting of any crop is quite sure to call
sooner or later for measures to offset the stimulus which such plantings
offer to insect increase.
Reference may be made to a familiar nut plantation which illustrates a
natural result of neglecting one of the insect factors. This plantation
is the government's chestnut orchard at Bell, Maryland, which was
planted for scientific purpose some years ago by Dr. Van Fleet. This
orchard of around one thousand trees contains numerous species and
varieties of chestnut, some of which bear fruit every year. The various
scientific projects carried on in this orchard in the past have all been
of such a nature that they called for no consideration of weevil
increase. Many nuts have been allowed to lie under the trees until the
weevil larvae issued and entered the soil. This has resulted in a
constant increase of weevils until infestation of the nuts became
practically one-hundred per cent. All nuts of the crop of 1922 were so
wormy that when planted they failed to germinate. Injury to the crop of
1923 seemed somewhat less severe, but its extent may be indicated by the
fact that 3080 nuts from this orchard which were kept by the speaker in
rearing jars yielded 11,085 worms. In the woods adjacent to the orchard
the native chestnut trees are disap
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