I understand that others have done
the same thing. Mr. P. A. Dupont, I believe, on his fine estate near
Wilmington, tried to spray a few chestnut trees with Bordeaux mixture,
and I understand he gave it up as a physical failure, to say nothing of
the cost. Am I right about that?

DR. METCALF: That is my understanding, that he was dealing with large
trees and failed.

A MEMBER: Well, did you succeed with small ones?

DR. METCALF: In the line of spraying? That is a long story, and I
suggest that Mr. Hunt answer that.

MR. HUNT: In the spraying work conducted on Dr. Smith's place at
Bluemont, Va., we had 2500 numbered trees under observation; about 1500
of them being sprayed. Equal numbers of trees were sprayed with Bordeaux
and with lime-sulphur. The number of sprayings given different lots of
trees varied, but even trees sprayed as often as every fifteen days
blighted in a number of instances. While I did not get a greatly reduced
percentage of blight (approximately 50 per cent) among the sprayed trees
taken as a whole, the difference between individual plots seemed to
depend rather on location in the orchard, as some blocks of unsprayed
trees showed practically no blight and some blocks of sprayed trees
showed considerable blight. I might say that the grafted trees did not
blight nearly so heavily as the ungrafted trees. So far as any real
success is concerned there was none. It would cost over one hundred
dollars per acre per year to spray as often as some of the trees were
sprayed, and it wouldn't control the blight. So I wouldn't consider it
at all practicable.

THE SECRETARY: What is the reason that the grafted trees blighted less
than the ungrafted?

MR. HUNT: Well, I wouldn't pretend to say as to that, except that it is
so. I had each tree numbered and kept an individual record of all the
trees, and I found--I have forgotten the exact figures--but there was
about three-fifths as much blight among the grafted trees as among the
ungrafted trees. Of course, they are an imported variety, I believe, and
it may be that on that account they may have developed some resistance.
But Mr. Van Fleet may know more about that.

DR. METCALF: There seems to be some evidence that the imported European
varieties have a slight degree of resistance, not enough to count, but
enough to show in that fraction that Mr. Hunt gave.

THE SECRETARY: It is only a varietal condition, then, not from the fact
of grafting, but simply bec