work is out
of my line.

Mr. Chase: Does anyone else have a comment on that? Dr. Cross, did you
hear the question?

Dr. Cross: I didn't get his question.

Mr. Chase: Would you stand and repeat your question?

A Member: Is there a spray that we can use for combating the insect
pests of our trees that when it is washed off and goes into the soil
doesn't kill our soil friends. We have the friendly bacteria in the
soil, as well as insect and worm life. Do we have a spray that will be
neutralized as it hits the soil so we can spray the tree and not kill
our lower friends?

Dr. Cross: Sorry, Mr. Chase, that's beyond me.

Mr. Gravatt: You are thinking of arsenate of lead poisoning the soil
where you keep on spraying with it?

A Member: Yes.

Mr. Gravatt: I think DDT may build up a little in the soil, but it is
broken down, isn't it, Dr. Crane?

Dr. Crane: Yes, DDT is broken down and it is not a fungicide and it is
not a bactericide. It is an insecticide that kills insects through
affecting the nervous system, according to my understanding of it. I am
not an entomologist, but that's what the entomologists say. So far we
haven't any evidence to my knowledge of any build-up of DDT in soils
that has been detrimental. I don't know what the situation would be if
DDT was used to the same extent as arsenate of lead. It was not uncommon
for some growers to put on anywhere from 6 to 15 lead sprays in a season
in order to control codling moth, as they used to do in certain apple
orchards, particularly in the West.

I was talking to Dr. Van Leeuwen just a day or two before I had to leave
for the meeting, and he is not ready yet to say anything about it, but
he has already tested some very promising insecticides as far as the
control of weevil is concerned. This DDT and some of the other new
insecticides are very easily decomposed, and, of course, that's one of
the disadvantages of them. Under certain climatic conditions they would
need to be less readily decomposed to give control over a longer period.
I know that we have not had enough experience to know all about those
new spray materials.

Mr. McDaniel: There has been one instance reported where DDT _in the
soil_ was injurious to fruit plant growth. That was Goldsworthy's and
Dunegan's work on strawberries. Where they used large amounts of
technical DDT in the soil, they found that it inhibited the growth of
the strawberry plant. I believe that's the only instance I've