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 heard of, where soil application of DDT hurt growth of fruit plants. Benzene hexachloride, and some other chlorinated hydrocarbons, and parathion actually appeared to have a stimulating effect on the berry plants.[14]
Mr. Frye: Why would there be any more danger of affecting the soil in a chestnut orchard than there would in the apple and peach orchard by spraying seven, eight and ten times? That's the only question that arises with me.
Mr. Chase: Let's get back to chestnuts specifically, now, gentlemen.
Mr. Kays (Oklahoma A. & M. College): Since I don't come from a chestnut area, my impression of the nut samples supplied by Mr. Moore of Auburn, was: "I'd like them if they had salted them." I am wondering if it wouldn't have affected their rancidity if they had been treated—salting material added, prior to or in the process somewhere along the line.