ons of any kind soon after
hard freezing weather. I have found scions of English and Japanese
walnuts, cut from trees in this condition, to be practically worthless
for propagation, although they may have been cut in late winter long
before the sap gets up in the tree naturally." This warning would
undoubtedly apply to the butternut as it bleeds freely when cut. Another
pitfall for the inexperienced propagator lies in storing scions in
packing material that is too moist. Sphagnum is commonly used. It should
be no more than slightly moist to the touch.
If left to run wild, the butternut curculios are a serious menace to the
butternut, the Japanese walnut and the Persian walnut. Their life
history as described at length in U.S.D.A. bulletin 1066, is briefly as
follows: The beetles (called elephant bugs by some because the side view
resembles the elephant) spend the winter in the ground. As soon as new
growth appears on the host tree they begin feeding on the tender leaves
and stems. Soon they begin laying their eggs in crescent shaped
punctures which they cut in the new shoots and nutlets. The larvae hatch
in a few days and tunnel through the pith of the shoots seriously
injuring and stunting their growth while the infested nuts soon fall
from the tree. The eggs may be laid from late May to early August. They
hatch in a few days. The larvae complete their growth in four or five
weeks when they enter the ground to pupate. In about a month they emerge
as adult beetles and begin feeding on leaves and leaf stems as their
parents did in the spring, but they will do no egg laying until the
following spring. Poison spray applied in early spring and again in late
August and September should so reduce their numbers that they will not
become a serious pest. Our State Experiment Station suggests the use of
a cryolite spray as it is more effective against curculios than
arsenical sprays and less likely to injure tender walnut foliage. The
Mitchell hybrid, (butternut x heartnut) with us, appears to have natural
immunity to the curculio. This brings to mind a secondary but very
important reason for finding better butternuts,--namely that they may be
used as a starting point for the super variety that someone should give
the world from his long rows of crosses between the best butternuts and
the best heartnuts.
The nut growers of this country are indebted to Dr. Arthur H. Graves of
the Brooklyn Botanic Garden for a complete study of
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