Part 5

There is no doubt that in an orchard tree, in chestnut orchards, the disease can be controlled within reason by the cutting out method that has long been advocated, but the point is that the margin of profit on the chestnut is not sufficient to make that method pay, and whenever members of this Association or others interested in the propagation of chestnuts have written to me for advice I have simply advised them not to plant chestnuts at present. I cannot see at the present time, that any attempt at control is profitable. That is a very different thing from saying that it can not be done, or that it may not later become profitable.

A few words regarding the method of spread of the disease. In 1908, when the office of which I have charge was first organized, Professor Collins, who has addressed this Association a number of times regarding this disease, visited a number of orchards and nurseries in the Eastern States, going as far as southern Virginia to the south, and west as far as York county, Pennsylvania, Although that was comparatively early in the progress of the disease, wherever he went, without exception, where there was a nursery, he found the disease present and spreading onto the native trees. There were, however, several established orchards which he visited where that was not the case, where the disease was not present. It has been brought out repeatedly that, while the chestnut blight is marvelously adapted to spread by natural means--wind, birds, insects, rain, all the ways in which a plant disease ordinarily spreads--the way in which it spreads over great areas and through great distances is on chestnut nursery stock.

In that connection, then, I may briefly discuss the present range of the disease so far as we know it, outside of the natural range of the chestnut tree. South of Virginia, so far as we know, the disease is present at only one point (Greensboro, N. C.), where it was introduced in a nursery and spread to native trees. In stating this area of distribution, I ought to say that for about a year and a half we have made no special effort to determine the range of this disease. I mean we have not gone out of our way to do it. We have simply collected such evidence as has come to hand casually, and so it may be that there are now other points of infection in North Carolina, or south of there, but, if so, we do not know of them. In Ohio, the disease is present at three points, of which one is a large and serious infection at Painesville. In Iowa, it is present at one point, Shenandoah, in a nursery. In Indiana, it is present at five points; in Nebraska, at two points. In Michigan, one point has been reported. In all of these cases it is in nurseries, or on very recently planted trees. There is, or was, an interesting point of infection in British Columbia. Probably the trees there are all dead by this time, but that point is very interesting as being probably an independent importation from the Orient.

There needs to be little said as to how the disease is spreading in this area. Perhaps the best thing I can do is to read some letters that have come to my attention:

"MICHIGAN AGRICULTURAL COLLEGE, "EAST LANSING, "Aug. 18, 1916.

"Dr. Haven Metcalf, "U. S. Dept. of Agriculture, "Washington, D. C.

"Dear Mr. Metcalf:

"Last December, the Forestry Department of this College ordered of Glen Bros., Glenwood Nurseries, Rochester, New York, five 6-foot trees of the Sober Paragon chestnut. These were shipped to them April 4th and were almost immediately planted in the Forestry Nursery here. About six or eight weeks ago, the Forestry Department noticed that these trees were dying and called our attention to this matter about four weeks ago. I examined the trees in company with Mr. J. H. Muncie, one of our assistants, and found all the external appearances of Chestnut Blight with, however, only a very few imperfectly developed pycnidia. We brought pieces of the bark of these trees into the laboratory and made cultures and obtained the typical mycelium of chestnut blight. The trees have been removed and we now have them in our laboratory.

"I am calling this to your attention as the trees were doubtless infected when shipped. I feel that you ought to know that this firm is sending out diseased trees.

"Very truly yours, "(Signed,) ERNEST A. BESSEY, "Professor of Botany."

The following is an extract from a letter from Frank N. Wallace, State Entomologist of Indiana, dated July 13, 1916:

"My Dear Sir:

"Under separate cover I am sending you some samples of chestnut blight which I secured from some trees shipped by Mr. C. K. Sober, Lewisburg, Pa. Mr. Sober doubts that we have even seen a case of chestnut blight and wanted some samples and I sent him the other half of the samples which I am sending you.

"I have been trying to check up on some of Mr. Sober's trees and so far I have found nearly fifty per cent of them have died from chestnut blight disease."

The samples sent with this letter showed typical chestnut blight.

Some months ago Dr. W. H. Long, of Albuquerque, New Mexico, became interested in the possibility of growing chestnuts in that country and communicated with Glen Brothers, of Rochester, N. Y., to secure certain information regarding them. He secured the information he wanted and also some that was slightly gratuitous. I will read extracts from the two letters:

"In regard to the blight, which you call the Eastern Chestnut Canker, would say that this tree is practically immune from this disease, and you would stand no more chance of having your chestnut trees infected with the blight should you plant them, than you would if you planted apple trees, of having them infected with the San Jose Scale or peach trees, of the Peach Blight.

"There are over half a million trees at the famous Sober orchard in Paxinos, Pa., none of which have the blight, and yet the blight rages all around them in the American Sweet Chestnut groves that are all through the mountain. Further evidence of its immunity from this disease we cannot guarantee. We think this speaks for itself.

"We believe that if you would investigate this variety that you would plant an orchard of Sober Paragon Chestnut trees, even if not a very large one. We should like very much, indeed, to serve you and shall give our personal attention to the selection and shipment of such trees as you may require.

"Very truly yours, "GLEN BROS., INC. GM-AB "(s) JOHN G. MAYO."

* * * * *

THE PRESIDENT: Would you mind giving us the date of that last letter?

DR. METCALF: That is October 20, 1915.

The other letter signed by Mr. Mayo is as follows, and is dated Oct. 29, 1915:

"Replying to your October 25th letter we do not think that you or your friend need have the least anxiety on account of the chestnut blight reaching your section. This disease seems to be confined to a very small area in northeastern New Jersey, southeastern New York, and southwestern Connecticut. The disease has been in existence in this country since 1842, it has made very little progress, and the highest authorities now state that it seems to be on the wane." (Laughter.)

* * * * *

MR. LITTLEPAGE: Do the experiments of the Department show any possibility of control of the disease?

DR. METCALF: I don't think that there are any methods of control which can profitably be applied to orchard trees under present commercial conditions. If a man has a few orchard trees which he regards as novelties and to which he is prepared to give very careful attention, I think the disease can be controlled. So far as I can see, the only hope of commercial control lies in none of the present varieties, but in Dr. Van Fleet's hybrids, possibly in the Chinese chestnut, and, aside from the objectionable qualities of the Japanese nut in certain strains of Japanese. With the rapid withdrawal of the wild chestnuts from the market, however, the price of chestnuts may rise, and control methods in orchards become practicable.

MR. LITTLEPAGE: Mr. McCoy has been in Pennsylvania and has come back with the very optimistic idea that the chestnut blight was under control up there. I took him out on my farm in Maryland and showed him my trees, and that the only thing that could destroy the trees faster than the blight is a forest fire.

DR. METCALF: Exactly.

THE PRESIDENT: I believe, Dr. Metcalf, you conducted a series of spraying experiments recently, and 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 because of a different variety?

MR. HUNT: Oh, yes, I think so.

MR. LITTLEPAGE: Mr. President, in view of this information about the chestnut, is there the slightest use in the world for this Association to encourage anybody to plant chestnuts anywhere in the United States?

THE PRESIDENT: Dr. Kellerman is here, and I wish to refer to him Mr. Littlepage's question with a slight addition. Is there, first, any prospect of any place staying immune? Second, would it not be to the advantage of the country if the sale of chestnut stock were stopped?

DR. KARL F. KELLERMAN: Mr. President, to answer those questions involves a rather large contract on my part. (Laughter). In the first place, the problem of growing and marketing chestnuts, I think, is one that I could hardly be expected fairly to discuss. I am here rather to explain the attitude and action of the Federal Horticultural Board than to try to give any constructive advice to the nut growers.

The Federal Horticultural Board is a board of five men to advise the Secretary of Agriculture in establishing plant quarantines, either on the introduction of plant material into the United States, or on the movement of plant material inside the United States within the quarantined areas. The Horticultural Board, therefore, has to deal more with actual conditions than with outlining such policies as your chairman has asked me to outline.

THE PRESIDENT: Excuse me, Dr. Kellerman, but we wish to know if there is, in your opinion, any prospect of any region remaining immune?

DR. KELLERMAN: Well, even that is going rather further than I would like to go, and yet the negative answer to that question is practically the basis on which the Federal Horticultural Board decided that it was impracticable to quarantine infected areas at the present time. The evidence at hand appears to indicate conclusively that if the trees that are to be grown are distinctly susceptible to the disease they will almost certainly have an opportunity to become infected, no matter what part of the United States they may be grown in. Now, whether that infection would be a matter of a few months, or a few years, or a few decades, of course, would be altogether a matter of chance, but, with the wide distribution of nursery stock that is infected, with native chestnuts rather generally infected and continuing to be infected, and with practically no chance of preventing the continuation of the disease in the native chestnuts, abundant sources for infection of susceptible material appear to exist. For that reason, it appears to be, from an economic standpoint, inadvisable to attempt to check the disease through the establishment of quarantines.

THE PRESIDENT: Dr. Kellerman, you have answered my first question to perfection, and now I want to ask the second one. If this blight is practically a sure-kill, isn't it wrong to permit people to spend money in the hope that, in some way, they are going to escape it? And if that is the case, why shouldn't the whole traffic in chestnut trees be stopped, with the possible exception of experimental things, which might be allowed with the direct permission of some governmental board?

DR. KELLERMAN: That is a question that is very much harder to answer. There might be favored regions where orchard culture of the chestnut could go on for a considerable term of years before infections became general and before the industry would be stifled because of this disease. That is merely a matter of conjecture, as I see it. We have so little evidence as to the speed with which a paying orchard business can be developed in a new locality, so little evidence as to how the disease may act under widely separated climatic conditions, that I don't feel that we are prepared to say definitely that the industry is bound to fail in every place where it is tried. Personally, I think that it ought to be considered only on an experimental basis, but that represents merely my personal opinion, and I doubt whether there is any effective means for establishing a policy of that sort. It might be possible for the general advice to be given that there was danger in any orchard planting of chestnuts, no matter where it might be undertaken, and of a comparatively rapid loss through the chestnut blight. I doubt whether more than that would be feasible.

THE PRESIDENT: I have been enthusiastic over the chestnut for twenty years this season, and these are matters in which I am greatly interested. As I see it, the problem is one that is really much bigger than the chestnut. The whole field of nut growing, which is now on the edge of great accomplishments, is likely to be seriously injured, because the most conspicuous thing in nut growing is the taking advertisement of the firm whose bad trees have been referred to by Dr. Metcalf. I think we do not appreciate the seriousness of the situation. The firm Dr. Metcalf referred to is selling trees that are diseased in places where they are sure to die quickly. Other men are similarly selling trees, with less skillful advertising, perhaps, but probably no less diseased. Most of these nurserymen may be honest in their belief that they are putting out stock that is not diseased. But in the infant trees it is almost impossible to detect the blight, so that the tree goes out looking like a perfectly good one. It may be two or three seasons before it dies.

Now, the economic aspects are these: Who should stand the loss, the man in the nursery or the man in the orchard? It is a toss-up, it seems to me at present, with the results apparently in favor of the nurseryman rather than in favor of the citizen. The people who have an interest in nut growing are going to have that interest lessened or destroyed by beginning with a bad kind of tree. There are possibilities of a great national injury, as I see it, if we let this thing go on.

DR. KELLERMAN: Well, as a constructive policy for aiding in the establishment of nut culture, I think your policy is sound, but as a question of economics of operation, I doubt whether any plan of that sort can be established, beyond the plan of merely giving the general advice that such planting is attended with very grave risks.

THE PRESIDENT: Have you not authority, or does not authority exist, to prohibit shipment?

DR. KELLERMAN: The plant quarantine act gives the Department authority to quarantine infected areas and to place certain restrictions on shipments. To place any such restriction, however, it must be plainly established that beneficial results are going to result, not to a

## particular industry necessarily, but to the general public. The

difficulty in establishing a quarantine on the shipment of nursery stock is the apparent impossibility of saying that that is going to stop the spread of the disease. That is one question. The other problem is the difficulty of determining what is infected territory and what is not. We have very serious difficulty in making regulations, excepting as between definitely infected territory and definitely clean territory.

THE PRESIDENT: And you don't have the authority to make a sweeping, blanket prohibition of the shipment of a certain thing?

DR. KELLERMAN: No, we haven't that authority.

MR. M. P. REED: We put a clause in the printed matter that goes out with all of our shipments saying that chestnuts are subject to blight, and that we don't recommend their planting. I think if nurserymen all followed that principle everybody would buy with their eyes open.

THE PRESIDENT: I am sorry you are so lonely in the business. (Laughter.)

MR. LITTLEPAGE: As regards the possibility, or the impossibility, of doing any good to the chestnut industry by quarantining it, I fully agree with Dr. Kellerman. I think any attempt of the Board to quarantine, so far as benefit to the prospective chestnut grower is concerned, is perfectly useless.

DR. ROBERT T. MORRIS: It seems to me it may be resolved into a very simple proposition. Now, chestnuts may be raised in orchard form if we spray with Bordeaux mixture, and cut out blight when it appears. I do it. They live. Those that are not sprayed die, unless given tiresome attention. That settles that question for my part. Chestnuts may not be raised in forest form because it does not pay to spray and cut to that extent. But chestnuts may be raised profitably in orchard form by people who are willing to take the trouble to spray them, and to cut out blight early. It seems to me that people should be properly warned that they may plant chestnuts in orchard form provided they are willing to look after them, otherwise we ought to guard against the public buying chestnut trees, unwarned.

MR. LITTLEPAGE: Dr. Morris, were you in when Mr. Hunt made his statement?

DR. MORRIS: I got in late.

MR. HUNT: I sprayed fifteen times, every two or three days during the blossoming season.

DR. MORRIS: I used arsenate of lead with my Bordeaux mixture for the reason that it is convenient. That makes it stick ever so much tighter. Now, that may be a feature of my confidence. Three or four heavy storms will not wash off my Bordeaux mixed, applied in that way, with arsenate of lead.

MR. HUNT: Well, my trees are dying right along.

DR. MORRIS: I am right in the midst of the worst chestnut blight conditions. The only kinds I have that are not blighted are sprayed trees, and chestnuts of kind that resist the blight. I had twenty-six kinds from different parts of the world to test out in the blight question. One kind from Manchuria is very blight-resistant. I find that our American chinquapin, both our eastern form and the western tree form are both blight-resistant. Also the alder-leaf chestnut. That is my experience. Those four chestnuts are practically immune, and on my property American chestnuts dying all around them.

I have one particular variety of American chestnut that I think a great deal of. It was one of the first trees to go down from the blight. Stump sprouts from this tree I have grafted on other stocks, on the common American, and recently on chinquapin. The sprayed ones are all alive; the unsprayed ones are not alive. Now, that is a matter of locality, perhaps.

THE PRESIDENT: Dr. Morris, I detect a possible explanation for difference of results. Mr. Hunt's trees were sixteen or seventeen years old. Dr. Metcalf tells us, however, that young trees are relatively immune. How old are yours?

DR. MORRIS: Not over twelve years. No grafts on them over four years. That would make a difference.

MR. LITTLEPAGE: Well, Mr. Hunt did a good job of spraying. I saw his trees, and they were saturated.

MR. WEBER: Do they ever use a sticker in the Bordeaux?

A MEMBER: What preparation of Bordeaux mixture do you use, Dr. Morris?

DR. MORRIS: I use a commercial preparation called Pyrox.

MR. CARL J. POLL: Will the chestnut blight attack any other trees besides the chestnut?

DR. METCALF: Outside of the chestnut genus, that is, the genus Castanea, the disease goes on to a few other trees. A curious fact is that it will go on to the sweet gum, a tree not related at all, and it will go on to a few oaks, in no case enough to seriously damage them as it does the chestnuts, but enough so that those trees can easily be carriers of the disease.

THE PRESIDENT: I think we might pass from this funeral. We have a paper by Dr. Van Fleet, whose work, I suppose, is known to everybody here. The paper has been prepared by Dr. Van Fleet and will be read by the Secretary.

HYBRIDS AND OTHER NEW CHESTNUTS FOR BLIGHT DISTRICTS.

DR. WALTER VAN FLEET, WASHINGTON, D. C.