Concerning the question of carrying blight fifty miles, there's no telling how far birds will fly carrying the spores of Diaporthe upon their feet. The spores are viscid and adhere to the feet of beetles, or migratory birds which sometimes make long lateral flights following food, rather than direct flights north and south. It is quite easy to imagine birds carrying this Diaporthe over an interval of possibly fifty miles, making that distance in one night perhaps. Someone may have carried chestnuts in his pocket to give to his granddaughter fifty miles away, and in that way carried the blight. If any grafted trees have been carried fifty miles, or any railroad ties, with a little bark on, carried fifty miles and then thrown off, it might blight the chestnuts in that vicinity. One can have as much range of imagination as he pleases as Longfellow says, There is no limit to the imagination in connection with questions of spreading the blight of Diaporthe.
Some of the Japanese and Corean chestnuts and some of the Chinese chestnuts resist blight fairly well. Among my chinkapins, I have the common pumila and the Missouri variety of pumila, which grows in tree form forty or fifty feet high. I have the alder-leaf chestnut, which keeps green leaves till Christmas, sometimes till March when the snow buries them, and those comparatively young trees have shown no blight; but one hybrid, between the chinkapin and the American chestnut, about twelve years of age, has blighted several times. I have cut off the branches and kept it going, but this year I shall cut it down. It will start at the root and sprout up again. I thought I'd give up that hybrid, but having heard Col. Sober's report I will begin at the root and look after some of the sprouts. That hybrid is the only one of my chinkapin group that has blighted at all.
In regard to the use of bichloride of mercury or formaldehyde, it seems to me that formaldehyde will be a better germicide than bichloride of mercury, because bichloride of mercury coagulates the albuminous part of the plasm and may destroy the cell structure, whereas the formaldehyde will be more penetrating and less injurious. One would need to know how strong a formaldehyde solution can be used safely. I presume the most vulnerable part of the tree would be at the bud axils. Spraying must require considerable experience at the present time and is of doubtful efficiency for timber chestnuts I am sure. We would like very much to hear any further comment upon this subject.
Prof. Smith: Mr. Sober's orchard is so unusually large that evidently it does not apply to average cases. The average man is buying chestnut trees for the garden or yard or lane. Prof. Collins has an acre on the top of a hill at Atlantic Forge and there he has fought diligently with the skill of a highly trained man, and the blight is gradually driving him back. I think that in a short time the trees on Prof. Collins' acre will be gone. I believe we need much more information before we can offer any hope that chestnut trees from a nursery will be safe against blight. I should like to ask the Blight Commission if they are at the present time planning to breed immune strains of chestnuts, and if not, I wish to suggest that it is a piece of work well worthy of their consideration. They might try grafting on American stocks, or on their own seedlings, some of the Korean chestnuts, on any variety that promises resistance, and also hybridizing, with the hope of getting a good nut that will resist the blight.
The Chairman: That is a very important matter, no doubt. In regard to the few chestnuts bought for lanes and gardens, I know a good many men who have bought a few grafted chestnuts with the idea of setting out a number of acres if those few did well, being men of a conservative sort. Men of that sort are the ones we want to have in our Association. We want to have men who will buy four trees, and if they do well, set out four hundred acres. That is what a great many men have had in mind in buying two, four or six trees of any one kind; they want to try them out. That is the wise way, the conservative way, the truly progressive way. If we are going to have very large numbers of any one kind of chestnut set out, we must make a statement of the dangers, so that men may be forewarned. If they set them out without warning and are disappointed, they drop the entire subject and go to raising corn and hogs; and then, to save trouble, turn these hogs into the corn and get to doing things in the easiest way, rather than carry on the complicated methods of agriculture that belong to the spirit of the present time. I would like to know if many efforts are being made toward breeding immune kinds. I am at work on that myself.
Mr. Pierce: Our Commission has recently gotten, I think, about fifty pounds of Chinese chestnuts of several kinds, which they expect to plant for experiment. Besides that they have made some other arrangements of which I know very little. This investigation will take years. The Commission has been compelled to devote itself to so many lines of work that I am afraid this question has not been given the attention it might have had. I think in the future there will be a good deal done along that line.
Two of us have been given the title of tree surgeons, and we work, or make arrangements to have someone else work, sometimes the scout, in the orchards throughout the state. I have a list of two hundred owners of cultivated chestnut trees that I got in the last month from various sources. Anyone in Pennsylvania who has a cultivated chestnut tree, can send a postal card, get one of us out to examine the tree and see whether it is blighted, and we will demonstrate what can be done in the way of treating it. I have done that right along in the last two months. If it is only a single tree I cut out all I can myself.
The Chairman: There are two distinct questions; first, the chestnut as a food tree, and second, as a timber tree. Your work has been chiefly with the chestnut as a timber tree?
Mr. Pierce: No, mine has been mostly on the lawn, so that it is for nuts.
Experiments made on one or two species of Japanese chestnuts show about 9 per cent of tannin; the tannin in the American chestnut runs only 6 per cent and in the small American, runs less. We know that the Japanese is somewhat more immune than the American. We have already found that it has 50 per cent more tannin. I believe one of us wrote you about experiments to find out the percentage of tannin in Corean, North Japanese, South Japanese and Chinese chestnuts. The investigation will be carried on for the next two or three months.