en two or three articles published on it,
the best one probably by Humphrey in Massachusetts. I have an abstract
of that which can be copied in the proceedings, if you wish.
(See Appendix.)
The fact that this _Cryptosporella_ is related to the black knot of the
plum is an interesting feature; and that it attacks the growing canes
during the growing season and fruit during the fall and winter. He
suggests the treatment of removing all the infected branches during the
fall and winter. I would add to that, complete eradication of all
diseased branches of the host, and they are rather easily seen, in the
fall as soon as the leaves are off--then a thorough spraying with strong
Bordeaux mixture, at least 5-5-50, preferably stronger than that, of
course burning all the material that you cut out. One is at a
disadvantage if there are wild hazelnuts in the neighborhood. How to
handle that problem I am hardly prepared to state; perhaps, by
eradication of the wild hazelnut in the vicinity.
THE SECRETARY: I think that would be impossible in most regions.
PROFESSOR WAITE: Mr. Kerr had his growing on the eastern shore on an
island where there are no wild hazelnuts and they were not attacked by
the fungus.
A MEMBER: They are all dead now.
PROFESSOR WAITE: The number of sprayings during a season is an
undetermined question. It will be necessary, probably, to spray two or
three times. You can certainly protect the two-year wood in that way by
making a fall spraying and a spring spraying. This will keep them
thoroughly covered with Bordeaux mixture but whether or not three or
four sprayings are necessary remains to be tested.
THE CHAIRMAN: Are any varieties of European hazels immune?
PROFESSOR WAITE: I have not studied them enough to answer that question.
I don't know. They all seem to go down. Perhaps Dr. Deming can answer.
THE SECRETARY: I don't know.
PROFESSOR WAITE: I think that is all I want to say, except one thing,
and that is about the physiological aspect of these, diseases. I touched
upon that phase in discussing the matter of environment in the
introduction of foreigners to places where they are not adapted. In some
particular seasons and circumstances even the native trees suffer. One
type of injury which has caused great trouble with the English walnuts
and pecans, and also with apple trees and has also caused trouble with
our native red oaks, is freezing when the trees are in a non-resistant
condition.
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