DR. GRAVES: Dr. Caldwell is right about No. 58602 being a mixture. Dr. Gravatt could tell you about that. It is a strain coming from several trees. It's evidently a very fine type, and I think we ought to know for the record just what 58602 is.
DR. GRAVATT: Professor Reisner's 58602 that Dr. Diller has been testing so widely is made up from a collection of seed from a number of isolated valleys of the Nanking area. It is rather southern in its native home, but Dr. Diller's tests and other tests have shown that it's hardy up north and it's hardy down south. As some of you have noticed, the nuts are very variable, with a number of different types mixed in together.
Dr. Diller and I have been discussing the question of hybrid vigor. It may be involved that each of these seedlings is a cross between different local strains. We must remember that the foresters have gone into this question of hardiness in great detail. You will find that you can't plant trees in Germany in a certain area unless the parent trees grew in a certain area, with comparable altitude and latitude. Minimum and maximum temperatures and other factors are also taken into consideration.
Pennsylvania started a program along the same line. They have divided their state into about five areas, and in each of those areas they are locating sources of seed that are going to be suited to those areas. They have evidence that many of these Chinese introductions coming from way down south are going to be hardy way up north, but in this matter of hardiness you sometimes have to wait for 50 or 100 years before you are sure of your conclusions.
DR. CRANE: That's right.
The next question I was going to ask these growers in the areas growing chestnuts is how much trouble they have had with hardiness or cold injury to chestnut trees that they have had. Has there been any?
MR. STOKE: I have had none.
MR. SILVIS: We have had none in Massillon.
DR. CRANE: Wilson, how about Georgia?
MR. WILSON: None.