Chapter XI: Section X: Amendments to By-Laws (4)

Another way to damage a tree is to keep it growing late in the fall by cultivation and fertilizers so that it does not harden off properly. Many plantings, representing heavy investments, fail because of lack of organic matter in the soil. This is related to water-holding and water-supplying capacity of the soil, and lack of proper fertilizer. Dr. Harley L. Crane and his assistants, in their work with tung and pecan trees, have shown the vital need for certain elements on some soils. Trees weakened by the lack of these elements are early prey for some diseases. The element most frequently deficient is nitrogen, but sometimes boron, copper, or iron is lacking; or the elements are not in balance, because of the excess of some, or the lack of others.

By adjusting the various soil, water, and site factors necessary for a continuous, vigorous growth of trees, many so-called disease conditions are eliminated. Many fungi and viruses, however, will attack trees in the pink of condition; a few of the more important of these are treated in the following sections.

+Chestnut Blight+

The destruction by blight of the native stands of the American chestnut, and of the small eastern orchard industry based on European and American chestnuts and their hybrids is almost complete. Blight has been found in the planted European chestnut orchards of the Pacific Coast from time to time, but it has been kept under control by eradication. Chestnut trees or nuts from the eastern States, where blight is common, should not be shipped into the Rocky Mountain or Pacific Coast States.

Finding the Asiatic chestnuts resistant to the blight, the Division of Forest Pathology sent R. Kent Beattie to Asia to make selections of chestnuts for introduction into this country. Later Peter Liu, a Chinese collector who worked with Mr. Beattie, continued to select Chinese chestnuts for introduction. These introductions, together with the earlier ones made by the Division of Plant Exploration and Introduction, were grown at Chico, Calif., Savannah, Ga., and Bell, or Glenn Dale, Md. Altogether some 300,000 chestnut trees, of pure species and hybrids, were distributed to cooperators for forest and orchard plantings. (Fig. 1.) These constituted a fine lot of material from many parts of Asia as a basis for selecting the best ones for our use. Private nurseries and State game and forestry departments are now growing these chestnuts and the Division of Forest Pathology has discontinued general distribution of trees to cooperators.

Chinese chestnuts have proved to be the most valuable for forest, orchard and ornamental use. The Japanese chestnut is being discriminated against because of the poor quality of its nuts. Orchardists having mixed plantings containing Japanese chestnuts are advised to top work the trees or remove them, if the seed is to be used for plantings. In fact, for orchard plantings, nuts should be used only from the best individual trees of the Chinese chestnut.

The Chinese chestnut should be planted on sites with good air drainage as it is very susceptible to injury from early-fall or late-spring freezes. Many persons think their trees have been killed by the blight when the primary cause of the trouble was injury to the trunk by freezing followed by growth of the blight organism over the injured parts. This fungus may grow for many years in the outer layers of the bark without doing any material damage to the tree. An important factor in resistance of the Chinese chestnuts to the blight is to keep the trees growing vigorously. Avoid late growth in the fall as this favors fall freezing damage.

+Nut Spoilage+

In the Southern States one of the most serious problems with some selections of the Chinese chestnut is the spoilage of the nuts. Marvin E. Fowler made a study of this trouble at Savannah, Ga., and found that most of the trouble in that restricted area was caused by a Gleoesporium-like fungus that infects the nuts at the tip.[10] Because spraying experiments did not give control, the more susceptible trees have been removed. In most parts of the South, however, this fungus is not the primary cause of nut spoilage and the limited work so far carried out has not revealed the cause. Part of the trouble may be due to physiological break-down. As individual trees vary greatly in susceptibility to this deterioration of the nuts, orchardists are advised to top work or eliminate the more susceptible trees. Some people have believed that exposure of the nuts to the hot sun while in the bur or on the ground may cause damage. The market for Chinese chestnuts can be ruined by shipping nuts that are partly spoiled by the time they reach the consumer.

[Footnote 10: Gravatt, G. F., and Marvin E. Fowler. Diseases of chestnut trees and nuts. Northern Nut Growers Assoc. Rept. (1940) 31: 110-113. 1941.]

+Phytophthora Root Disease of Chestnut+

Phytophthora root disease, caused by _Phytophthora cinnamomi_, is treated briefly here, and interested nut growers can consult the detailed earlier article.[11] Briefly, this fungus is considered as introduced into this country over a hundred years ago. It killed the chestnut and chinkapin growth over large areas in the southern States. Asiatic chestnuts are highly resistant to this disease, and when grown on well-drained soils have not been damaged. Our test plantings of Chinese chestnuts growing in the same soils where susceptible trees of American and European chestnuts were killed, continue to make a vigorous growth. The European and American chestnuts and their hybrids growing in the western States are in danger from this fungus as it has now been reported in the West. This same fungus sometimes kills thousands of young nursery trees of the black walnut, but these epidemics are usually brought on by unusual weather conditions. Poor soil aeration, induced by excessive rainfall and poor drainage, makes ideal conditions for damage to the walnut and other hosts by _Phytophthora_. Even the very resistant Chinese chestnut roots are invaded by the fungus when the soil remains waterlogged for extended periods.

+Brooming Disease of Walnut+

A systemic brooming disease, observed on planted walnuts as early as 1917, has been the subject of considerable discussion during recent years, because it has now spread widely into the native black walnut growth. In 1932 Waite published that he had been observing the disease for some 15 years but that "it was unknown on the black walnut in the wild in this country or on planted trees away from the Japanese walnut." The disease has continued to increase in prevalence in recent years and is now widely distributed in native black walnut growth in Tennessee, Virginia, District of Columbia, Maryland, Delaware, and New Jersey. This extensive spread into the native growth during the last 15 or 20 years and the fact that reports indicate that all of the early cases of the disease were found near nursery-grown trees offer some evidence that the disease is an importation from another area or continent into the eastern black walnut zone. From the literature and oral reports, it seems that the disease is now present also in North Carolina, West Virginia, Pennsylvania, New York, Ohio, and Michigan. Surveys probably would uncover the disease among native wild and planted walnuts in other States.

[Footnote 11: Crandall, B. S., G. F. Gravatt, and M. M. Ryan. Root diseases of Castanea species and some coniferous and broadleaf nursery stocks, caused by Phytophthora cinnamomi. Phytopathology 35: 162-180. Illus. 1945.]

+Economic Importance and Hosts+

The black walnut is a valuable native forest tree, widely but not abundantly distributed in the eastern United States. It is extensively planted as a forest tree. The numerous plantings and natural stands around farm homes, along fences, and in pastures are also very valuable. More and more grafted ornamentals, and orchards of black walnut are being planted. For these the per-tree investment is high.

The ultimate effect of the brooming disease on the black walnut is not known. Dr. Waite stated, "Trees even moderately attacked soon become worthless for nut production." Some affected black walnut trees, however, continue to produce small crops of nuts. Visible symptoms have been known to disappear. In addition, some seedlings, and probably large trees also, are infected without showing symptoms. Such observations indicate the complex nature of the disease. Detailed studies are needed, but at present this Division is not in position to do more than limited, part-time work on the disease.

The butternut, a widely distributed forest tree of minor importance, is seriously injured or killed by this disease. The disease severely damages or kills the Japanese walnut, which has been planted to a limited extent but is of little importance. According to Dr. Waite's report, the Persian, or English, walnut is attacked, but very few trees of this species are planted in the eastern States. Precautions should be taken to prevent the introduction of this disease into areas where it is not now present, particularly the western states.

Symptoms expressed by infected trees are viruslike, and Hutchins and Wester[12] were able to produce the brooming symptoms on a small number of trees by means of bark patch grafts, indicating that the brooming disease probably is caused by a virus.

+Description of Symptoms+

The entire range of symptoms of the brooming disease has not been determined. Symptoms are recognizable during mid-July but they are most pronounced during September and October. Curling and cupping of leaflets, chlorosis, narrowing and basal tapering of leaflets appear to be associated with early stages of the disease. On severely affected trees there are distinct broomlike growths at branch terminals, along primary or secondary branches, or on the main stem to the ground line (Fig. 2). The broomlike growths are formed by the continuing abnormal development of normally located buds into short, succulent branches. Upright, suckerlike branches appear on primary and secondary branches and on the main stem of the affected tree. (Fig. 3).

The broomed parts usually die back during the dormant period following their appearance. The dead brooms on trees that appear to be healthy during the early months of the growing-season indicate that the trees are infected. Usually the diseased trees, even those severely affected, exhibit normal growth during the early summer months.

Evidence that walnut trees may be infected for a considerable time prior to appearance of recognizable symptoms was obtained when 37 per cent of a total of 300 severely pruned trees exhibited brooming disease symptoms. These trees had looked healthy until they were pruned. Unpruned control trees showed a 4 per cent increase in disease during the same period.

[Footnote 12: Hutchins, Lee M., and Horace V. Wester. Graft-transmissible brooming disease of walnut. Phytopathology. 37 (1): 11. (Abstract) 1947.]

+Summary+

There is strong evidence that a virus disease is active among certain species of walnut in central and eastern United States. The disease exhibits distinctive symptoms and appears to damage infected trees, sometimes severely, over several growing seasons. Present data indicate that recognizable symptoms of the disease may not appear for some time after infection, unless the host is subjected to severe shock. Thus, nursery stock may be one means of spreading the disease into new areas. It is recommended, without experimental work to back up the recommendation, that walnut nurserymen remove infected trees in the vicinity of their nursery sites.

Investigation of this disease to the present time has been limited. General observations indicate that severely broomed trees produce poor nut crops. Mortality caused by the disease appears to be quite low among black walnut trees. Butternut and Japanese walnut trees are, in general, more severely affected by the disease than the black walnut and many seem to be killed by it, although the killing process is slow. As a result of experience with other virus diseases, orchardists who have only a few infected trees among their black walnuts are advised to remove them. Whether the disease can be kept under control by repeated roguing is uncertain. If an owner has just a few trees of value as ornamentals as well as nut producers, one hesitates to advise him to remove a lightly infected tree until more information is obtained concerning the disease.

This Division will welcome information from persons having experience with the brooming disease of walnut, as it is in a position to do only a limited amount of work on the disease.

+Persimmon Wilt+

Persimmon wilt is very destructive to the native persimmon (Fig. 4). It is caused by the fungus _Cephalosporium diospyri_, which was described in 1945 by Bowen S. Crandall[13]. The fungus grows in the wood of the trees, producing discolored streaks. Most trees are rapidly killed, with yellow, wilted leaves making quite a contrast to the normal green trees.

This disease was found in spots from central Tennessee south to the Gulf, east into Florida, and up the coast into North Carolina. The American persimmon seemed to be in danger, as this quickly killing disease appeared to be spreading. The limited work on this disease was discontinued because of the war and the transfer of Mr. Crandall to Peru. However, this summer Mr. Crandall and the senior writer spent two weeks surveying some of the old infections and nearby territory, and were pleased to note that the disease had made very little progress into new territory. On several small areas where the disease was present some six years ago practically all of the larger trees had been killed, but some new small trees were coming up. At Chattanooga National Park, where the wilt was rampant about six years ago, it is continuing to kill trees, but many new ones are coming up. No northward extension of the disease in Tennessee or North Carolina was noted in the limited time spent in inspection.

What does the disease mean to the grower of grafted persimmons, both native and Oriental? The Japanese or Chinese persimmons do not grow as well on their own roots, although they are quite safe that way as these two species are very resistant to the wilt. In the East, most of the Oriental persimmons are grafted on American root stocks, and trees in one case were killed by the wilt fungus getting in on the susceptible root stock. No attempts to control the wilt have been made, and these recommendations are based on procedure with other diseases and on knowledge of the spore production of this fungus. An owner of a valuable planting of grafted trees in a region where the disease is present should watch his trees for the first indication of trouble. The planting will be safer, if there are no nearby native trees; and if native trees are growing nearby and cannot be removed, they should be given a general inspection. Prompt removal and burning of any infected trees found is advisable. The fact that usually fungus spore production does not take place until after the tree has been dead for a while makes the prospect for control better than with most diseases. Care should be taken not to bring in scions or trees from infected areas.

Most members of the Northern Nut Growers Association have only a few grafted persimmon trees, usually located outside of the infected zone and therefore in little danger. Persimmon scions and trees should not be shipped from infected to healthy regions. The disease has not been reported in nurseries, but it could occur there because it attacks small trees.

[Footnote 13: Crandall, Bowen S. A new species of +Cephalosporium+ causing persimmon wilt. Mycologia 37 (4): 495-498. 1945.]

+Thyronectria Disease of Honeylocust+

Honeylocust is widely distributed both in native stands and in plantations. Some farmers plant this species or leave native trees in their pastures for the pods, which have a high sugar content, up to 38 per cent. J. C. Moore, of the Alabama Agricultural Experiment Station, reported preliminary tests indicating a per-acre yield of livestock feed equal to that of oats.

In many areas the growth of honeylocust is seriously affected by a canker and twig fungus, _Thyronectria austro-americana_. The disease often kills many twigs and branches and sometimes results in death of the tree. In most areas it causes only slight injury. Bowen S. Crandall and Jesse D. Diller have made a few observations on the prevalence and damage by this disease, which is present from New England south into the Gulf States and west into the Great Plains States.

The fungus causing this disease is morphologically somewhat similar to the chestnut blight fungus, having two spore stages produced in reddish-brown pinhead-size fruiting bodies on the bark. Cankers are produced on the smaller branches, but they usually are not noted until some of the affected ones wilt and die. In the exposed outer wood of a branch cut above or below the canker there are reddish-brown streaks several inches long, indicating that the fungus has grown in the vascular system.

As no control experiments are known, recommendations are based on general knowledge of sanitation. If an owner has only a few valuable planted trees, he should cut off the diseased parts a foot or more back from the lower edge of the affected bark and burn or bury them in the soil. If he has many trees scattered over extensive pasture areas, it is questionable whether any action other than elimination of the more susceptible trees is justified. We will be interested in the results obtained from control work.

* * * * *

President Davidson: Now I will turn over the chairmanship of the meeting to Mr. Chase, who will have charge of the Round Table Discussion.

Round Table Discussion on Chestnut Problems

SPENCER B. CHASE, Presiding

_Panel of Experts_: Max E. Hardy, Carroll D. Bush, H. F. Stoke, G. F. Gravatt, J. C. McDaniel.

Mr. Chase: Gentlemen, in the last hour and a half we have heard perhaps more about chestnuts from qualified specialists than we will ever hear in any meeting of ours, and we requested each one to withhold questions until this point. So now we will have some questions from the floor, please.

Mr. Slate: What is the present status of breeding chestnut species for timber purposes?

Mr. Gravatt: The prospects are coming along. We have one cross between a none-too-promising Chinese chestnut and an American chestnut, with a good bunch of hybrids and they are different from other hybrids. It looks like they will stand up against blight. They will have blight canker growth from 10 feet down to the ground but it doesn't go into the cambium region. It is too early to evaluate the hybrids, but they do have the upright form and rapid growth of the American chestnut.

Now when we take these first-generation hybrids, cross them back with the Chinese and get more resistance, as we have done so many times in the past, we lose that rapid and more upright growth habit of the American chestnut. But we have a lot more work to do before we are ready to say anything final on this question.

Dr. Arthur H. Graves, formerly at the Brooklyn Botanic Garden is now consulting pathologist at the New Haven, (Conn.) Experiment Station. We have been working with him and partially supporting his chestnut breeding for a good many years. He has a lot of hybrids up there. We expect to have something later, but have nothing to release yet.

A Member: Do you have any sprays to control diseases and insect pests in the tree that when they go into the soil won't destroy our ground friends?

Mr. Chase: Mr. Gravatt?

Mr. Gravatt: I don't know what insects you are after, in the first place. We have a lot of trouble with Japanese beetles. Around Washington, Dr. Crane's and my plantings there would be defoliated if they weren't sprayed for Japanese beetle control, and it is the same way with filberts.

A Member: The same sprays have a tendency to work against most of the pests, do they not? Of course, DDT will take one, the arsenate of lead takes another, Black Leaf 40 another, but if we had a spray that we can use around on--well, not limited to the chestnut--that would be neutralized in the earth. Now, we have a good deal of friendly bacteria and insects in the soil that we want to keep.

Mr. Gravatt: I would say that I am a pathologist, and insect 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 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.

Mr. J. C. Moore: I'd just like to say I have tried putting salt in the water, to boil the nuts with salt, and then I have tried shelling them and sprinkling salt, and I find that salt does not add anything to the flavor. Tasting the nuts raw, I, too, get the impression salt is what I want, but I haven't been able to add it satisfactorily. I don't say that it cannot be done.

Dr. MacDaniels: Mr. Chairman, in view of the whole situation of chestnut incompatibility of stock with scion, what would be the position that we in the Northern Nut Growers Association can take in advising people what kind of chestnuts they should plant? Should they be encouraged to try to get grafted trees? What should be our position?

Mr. Chase: Mr. Stoke, would you care to comment on that?

Mr. Stoke: You are asking me to stick out my neck, and it seems as if I have always done that. The Chinese chestnut is in the Johnny Appleseed stage, in my opinion, and we are investigating to find out the best varieties, that is, the best specimen, best performance, best quality, best in blight resistance, growth, and other qualities and when we winnow out all we have and arrive at the best, we are going to find--now, this is just my personal opinion--I will say that for myself I'd rather have one acre of the best selections we have budded or grafted--asexually propagated, than five acres of seedling trees as a financial good bet, because I say that one acre of our very best produce virtually as many nuts as five acres of seedlings. I have trees from seed I imported through the Yokahama Nursery Company, and I think it came from Korea. The nuts run very small, and compared with those I am sure the others will pay much better, and I think it would be profitable to pay three or four or five times as much for your trees if you get good trees of good, known varieties and grafted or budded.

Don't misunderstand me. We shouldn't ask the American public to wait until those can be furnished, because they won't wait, and they shouldn't. But I say as a commercial proposition, to plant trees commercially, I would exercise caution and I would encourage my customers to exercise caution unless they are willing to follow up and do their own top working later on, and a Chinese chestnut doesn't top work as readily as a black walnut.

Mr. Chase: I don't believe that's quite the answer he wanted. The comment that I think Dr. MacDaniels is after is what position should the Northern Nut Growers Association take in regard to planting seedlings or planting grafted stock. Is that the point?

Dr. MacDaniels: Yes, it seems to be seedlings against grafted stock.

Mr. Stoke: May I answer? I don't think the Northern Nut Growers Association should take _any_ position. They should present the facts and let the buyer decide. I don't think we need to go on record, and I don't think we should. There is too much diversity of opinion.

Dr. MacDaniels: Between ourselves--and this is not an academic question--we get continual inquiries regarding the Chinese chestnuts and what should they plant and where can they get the trees, and so forth. It isn't good enough in most of these cases to write several pages explaining what the whole situation is, the _if's_, _and's_, and _but's_. But I just wonder what the opinion is of the people who know best in this regard. Who has a good orchard of 20-year-old grafted Chinese chestnuts? Where are they? I don't know: I am asking for information.

Mr. Chase: Dr. Drain, are those trees you have grafted trees or seedling trees?

Dr. Drain (University of Tennessee): They are seedling trees. They have produced a rather nice quality nut, and we have enjoyed propagating seedlings from them. That's really all we know. We haven't grafted any.

Mr. Chase: Mac, would you care to comment on this?

Mr. McDaniel: I am ashamed to say that at present we have no grafted chestnut trees on my own north Alabama farms. We have about 50 trees that are 8-year-old seedlings from imported (Chinese) nuts, growing next to a commercial peach block, and find the production quite variable on the different trees. I am aiming at top-working most of these with the named varieties, beginning this year. At present I can't answer the question of seedlings vs grafted trees. I have been advising people who are interested in trying them in Tennessee that _for their first planting_ (to test the adaptability of their locations) they can get the seedlings generally quite a bit cheaper than the grafted trees. With the experience we have had over the State and the high mortality of trees, both grafted and seedling--killing of the tops and in some cases the whole tree--the seedling might be best economically _to begin their_ experimenting with. I am _not recommending_ that anyone plant seedlings commercially, but just in a small way for trial. They are well worth a trial anywhere peaches are doing well. When we find a _suitable site_, then is the time to think about using the more expensive grafted trees.

Pres. Davidson: I just want to give a little bit of my experience along that line. Way back in 1934 I planted a few seeds that I got from Amelia Riehl. They were nuts of the Riehl hybrids. [Ed. note: Mostly American--European crosses.] She named one Dan Patch and another Gibbons. They are now about 13 years old. Each of them is bearing burs this year. They have borne burs, a few of them, in the past, but no nuts. So far in 1948, the burs that have fallen to the ground, of course, have no nuts, but whether the burs that are still on the trees have nuts I don't know. I want to know whether those trees are normal---whether a hybrid of that kind is likely to be sterile or not. That's another matter that might be discussed. Anyhow, you are taking a chance, no question about that, when you plant seedlings.

Mr. Stoke: Mr. Chairman, if you will pardon me for saying one more word, here is a suggestion I will make. Now you can check for yourself. The whole thing hinges on whether we can get _permanent_ grafts on the tree and get the characteristics in the grafted tree that the parent has--in the good selected tree. Now you take the reports sent us by Mr. Hemming; you take the reports of the station at Albany--of individual trees in those plots. You take the worst trees and you will find they are nothing but boarders. You take the best and you will find they are very profitable. You take the average and it will fall somewhere in between.

Now, why keep a lot of boarders that don't pay--free boarders--or why use run-of-mine seedlings, _if_ we can graft successfully--and some people like to dispute that--and produce nothing but the best? And you can check it on any of those tables. [Mr. Hardy's paper.] We have a few tables in our former Reports. You can check it and figure it out for yourself.

Dr. Crane: To clear up this situation I wanted to ask Mr. Hardy a question, and then I wanted to make a statement. In this report from the 1938 and 1940 planting at Albany, Georgia, in the Brown tract in 1947 there were 188 trees that bore crops, but that planting consisted of 274 trees planted in 1938 and 60 trees planted in 1940. Why weren't those 274 trees plus those 60 trees represented in the 100 with the yield records of 1947?

Mr. Hardy: Dr. Crane knows the answer, so I will let him ask the question and answer it, too.

Dr. Crane: In 1936 we planted 1,000 trees of the same Peter Liu selections on the Station farm at Beltsville, Maryland. They were of the same number and letter designations as others that were distributed to cooperators. Out of the thousand trees that we planted on the Station farm some of them came into bearing at four and five years after planting. But the nuts were small in size and were not much good. With one or two exceptions, out of that planting there were none bearing satisfactorily to suit us after ten years. In 1945 we applied the ax, because a Chinese chestnut tree, from an orchard standpoint, if it's not in bearing in ten years after planting is not worth keeping. We haven't got time to wait. So out they came. And in addition to that we have had other trees that have done the same thing.

Now, out of this 274 plus the 60 at Albany, Georgia, we have three trees that we now figure are good enough to be raised to a variety status, plus possibly two or three more. Now, you can figure your percentage of good trees when you plant seeds.

Dr. Overholser: Mr. Chairman, may I ask a question, whether these three seedlings to which they propose to give variety status have been propagated in sufficient number that they are able to give distribution in other areas.

Mr. Hardy: Dr. Overholser, they are not available yet in quantity. That same answer is part of the answer I wanted to make to Dr. MacDaniels. The present situation in the chestnut industry is that there are very few nurserymen who know how to propagate nursery grafted trees successfully. There is going to have to be quite a bit of work done on that. If some of you here know how to do it, I would like to know, myself. There are a lot of nurserymen who would like to know, according to the reports I have, how to graft or bud a nursery chestnut tree.

As long as the situation is that way I would say to recommend seedling trees because of their low price, but--and every grower who has trees can fall in line with this--the seeds should be from properly culled-out orchards of the highest type, leaving nothing in there producing nuts or pollen but what is the highest type. I think all of you who have more than one type of chestnut in your plantings should cull them all down to the pure _Castanea mollissima_. I don't mean by cutting out the whole tree, but go ahead and top-work them. If they won't take the top, _then_ cut them out. But if you can top-work them and the grafting is good, you can increase your planting of good trees in that manner.

The improved quality of the seed will improve the quality of seedlings going to the buyer, and the chances of a higher percentage of good seedlings showing up will be greater. I think it will improve the industry through a period of years.

Dr. MacDaniels: I think I agree with his position. In fact, that's exactly what we are telling the inquiries that come in: At the present state of our knowledge, better try seedling trees.

But I didn't hear anybody get up and say they had an orchard of 20-year-old grafted chestnut trees. I have tried to get them, I have grafted successfully, I suppose, 7 or 8 different varieties on many different Chinese stocks that I have bought, or had given to me, and numbers of grafted trees. I have nothing left. They grow fine, 7 or 8 feet the first year, 3 or 4 feet the next year, then they go along for a while and then they die. In other words, there is an unsolved problem there, so that it seems to me at the present state of our knowledge we had better admit it and say, "If you are an amateur, you better get the best seedling trees that you can and wait awhile."

Mr. J. C. Moore: I just want to give some data on some of the class work at Auburn with Chinese chestnuts. We were studying Chinese seedlings, and we attempted to bud those Chinese chestnut seedlings, and on some of the larger seedlings we top-worked. We had some 3-year-old seedlings, and we top-worked the limbs. We put in patch buds, and we put in T-buds or shield buds, and in practically every case on some of the trees the buds stuck beautifully.

In June and again in August, with another class, we had the same results, either with T-bud or shield bud or patch bud. Some of the seedlings wouldn't take the buds at all. I can't think why one seedling would take 100 per cent of the buds and another seedling growing right by it wouldn't take any buds.

Mr. Weber: The oldsters here will remember Colonel C. K. Sober, one of our former members who propagated what he later named the Sober's Paragon chestnut. It was a grafted tree and apparently it was grafted successfully on native stocks, and it grew until the blight got it.

Dr. MacDaniels: I am not talking about European or American, I am talking about Chinese chestnuts.

Mr. O'Rourke: It may affect the nursery industry. The nurserymen are looking to the Northern Nut Growers Association, Federal bureaus and State experiment stations to guide them in the propagation of desirable trees. We know now that the Chinese chestnut is becoming quite prominent, is becoming quite popular in many sections of the country, and many nurserymen are now getting requests to supply the public in their states with Chinese chestnuts. They, in turn, would like to know what they should do. If they sell Chinese chestnut trees which have been propagated vegetatively and they only grow five, eight, 10 or 15 years and then die, it's going to come back on the nurserymen. They should like to know whether they should do that or whether they should rely upon seedlings which they can develop into pure lines as best they may.

Now, that really is a serious question. I am wondering from what Mr. Hardy has told us today if it may not be an understock problem, and if it is an understock problem--if there are certain strains of understock which are compatible with certain scions, possibly we should ask for some investigations, some more research to be done in this direction.

Then possibly, on the other hand, we should also ask that certain investigations be carried out so that we will have some idea of the inheritable characters that may be "fixed" through seed selection. I really think that this seed selection should be very seriously considered, and that nurserymen in particular and the public in general would benefit greatly by such consideration.

Mr. Hardy: Mr. Chase, may I make this suggestion: I think it is something that a number of individuals could try, perhaps they should be backed up by agricultural institutions, either Federal or State. We are all interested and concerned with stocks, and I think a large part of our trouble with grafting chestnuts is a stock-scion relationship.

We have some top-worked trees 13 years old that are just as healthy, just as normal as they can be. We have some top-worked trees of various ages below that. The graft-union is good; they are just as healthy and continue to be as productive and vigorous as the parent tree. Where there is incompatibility we run into difficulties very shortly. To a large extent I think we are involved with two problems in the trouble with incompatibility, or perhaps I should say the dying, of grafted trees. One is a stock-scion relationship, the other a mechanical problem.

I think there are these two types of incompatibilities. Now, as to the mechanical part--that can be improved through developing the art of grafting or budding, whichever works out best. The other will require quite a lot of study, perhaps the development of certain strains of the root stocks for certain scion varieties.

I have made this suggestion to two or three. I have started the work myself by putting out with friends two or three or four trees. After they get up to a size where I can top-work them, I will top-work with two varieties. Perhaps I will put Nanking and Kuling on two trees at one particular place. Two or three miles away I will put Kuling and Meiling on two others. At another place I will put Nanking and Meiling. I will get reciprocal pollination, because the chestnut is necessarily cross-pollinating.[15] I can then plant seedlings from both parents, each pollinated by the other. Then by grafting those varieties onto those seedlings stocks I can find out whether there is any reason to go into the work of developing seed orchards of two varieties whereby Meiling pollinated by Kuling may produce the best, most vigorous, most uniform seedlings on which Kuling can be propagated. And by propagating Kuling on such seedlings--the seedlings of such inheritance--we may get 100 per cent of good grafts.

The industry needs a lot of help, and I think it is a matter of time until those things are worked out, but it is going to take time and money and plenty of good effort to work out that problem. I think it probably should be worked out.

Mr. Bush: I don't like the word "incompatibility", and I hardly believe in it, and I presume most of you know that. I have Chinese on European stock, and it has been there for 20 years or more, _grafted high_. I have Chinese on Japanese grafted _under the ground_. I think a good deal of our damage is done from wind, from cold, and from sun on the graft _just above the ground_. I suspect that grafting at that point is what is the matter with many trees in the TVA plantings and others that had low survival. Of late years when I did the grafting (in the last five or six years) I cut the stock underneath the ground and stuck the graft under the ground and seemingly I got far better results. Some of those graft failures showed up. I laid that largely to mechanical damage, and again with the Japanese, particularly, I laid it on the time when the sap comes up. Call it what you will, but the timing of the growth of the two trees is different and we had trouble there. I have grafted some very widely different kinds of chestnuts on the tops of other chestnuts, and am getting them to grow. When we see the break start, we take a twig from below and break and put it above, cut through the cambium and nail it on and they will heal over and the defect disappears. So, again, it seems to be mechanical.

Mr. McDaniel: I believe from observations on a number of trees, particularly Dr. Richards' in West Tennessee, that a large part of our so-called incompatibility in this State is due to winter injury _to the stock_. So what Dr. Richards meant, evidently, was that he was rather successful in getting a "take" from last summer's propagation but the stock then failed below the union this spring. I saw his trees, and they had the typical discoloration of bark and the dying of various bark areas--these girdling the whole tree in a number of instances. [See Richards' paper in this report.] I would agree in general with what Mr. Bush has just said, but there are certain other instances in which we think the only word for what we see is "incompatibility."

Mr. Slate: What are the prospects of planting those low-grafted trees rather deep?

Mr. Bush: I think that if the roots started to die the grafted tree would start a root above the graft. The sap is going up from the root. It will go down and the root will start above the graft and go out above the graft, thus getting the tree on its own root.

Mr. Stoke: Since we got onto grafting, do you mind if I say a word? Here is a four-branch, top-worked specimen that I chopped off and brought with me. This first tree limb was still alive and had nuts on it, the second was dying and a third dead. This fourth union was still alive, but it was badly damaged, too. That's Illinois 31 -4 on Japanese. Here is another graft of Illinois 31 -4 on Japanese in a small tree, and if that's poor union, I am no grafter!

Mr. Hardy: Mr. Stoke, may I ask you this: Is this [small graft] on the same tree as this? [Indicating larger tree first referred to.]

Mr. Stoke: No. Those four grafts, you see, all went bad. This one is in perfect condition. But I am having a hard time keeping that Illinois 31 -4 alive. I had a union on _mollissima_ three inches in diameter and as perfect as this, two years ago. Last year it began to bulge at the point of union. The top wasn't feeding back to the root, and this year it is in bad condition,--foliage very small and it put on a very full crop of burs which will never mature, and it's going to pass out. It is about four inches in diameter now.

Last year to try to beat this thing I cut out the crown of a small _mollissima_ at the below-ground level and put in several grafts of this same Illinois 31 -4, and I got a nice growth, at least four feet high. When I dug it up to transplant it--it was right in my garden--I found I had a large callus more than an inch and a half in diameter at the union but no roots. I reset it, and I haven't ventured to see whether it was all right or not. This spring I tried again.

I have four little trees, one as high as my head, the others smaller. I grafted each one on branch roots just as they lay in the ground. Didn't dig them up and they grew nicely, and along in July I went around and spaded them deeply and thought perhaps that would produce roots. About a week ago I examined one. I have a magnificent callus but no roots yet above the union. What the ultimate results will be I don't know.

With that particular hybrid I want to try one more thing. I want to grow seedlings of the European chestnut, cut them below the ground, graft Illinois 31 -4 on the root and it may make a union that will not fail, because the European is a very robust grower, and by being grafted under the ground the stock will be away from blight organisms.

[Editor's Note: Mr. C. A. Reed is naming this variety (Ill. 31-4) "Colby" in honor of the originator, Dr. Arthur S. Colby.]

Mr. Hirschi: I would like to say I put on hybrids similar to that Illinois 31 -4 and they grew the first year, and just made a bulky knot right at the point of union and died the second year.

Mr. McDaniel: What was that combination?

Mr. Hirschi: That was _mollissima_ stock.

Now, speaking about the varieties--this is in Oklahoma--I have tried practically all the older varieties and I have tried some Abundance grafts this last year. I have some Abundance grafts that are two years old that are producing. They have the most vigorous growth of anything, and in our climate we have to have vigor.

I grafted a lot of the Abundance scions on Hobson seedlings. I started out to grow an orchard from Hobson seedlings, and I found out that out of 50 splice grafts of Abundance that I put in Hobson seedlings in 1948, forty-eight grew, and they were put on rather late, in April. That's a little late for us. I have the idea--I don't know whether I am right or not--that if the Abundance proves out as our best variety, we can grow seed for stock of the Abundance and then graft the Abundance back on the seedling from Abundance. If there is so much to this incompatibility, I should overcome it by doing that very thing.

Personally I think it is a crime that thousands of trees--almost millions--are being put out by nurserymen as seedling trees, and if you will note in their price lists they have "6 to 12 inches" and "12 to 18 inches", "2 to 3 feet" and "3 to 4 feet." I venture to say that those are probably all the same age. How would you like to plant some of those 12-inch trees? Somebody is going to get hurt!

Mr. Bush: I'd like to say that you can propagate the Chinese chestnut by layering if you want to, and that will put it on its own. Put a wedge on it or girdle it and keep it damp through the summer.

Pres. Davidson: I think Dr. MacDaniels' question is still not answered. I do think that if a nurseryman sells a seedling he ought to definitely _say that it is a seedling_ and not merely that it is a "blight-resistant chestnut," or something of that sort. He should actually tell the public what he is selling.

Now, then, there seem to be reasons why in some instances a man is justified in planting seedlings when it comes to Chinese chestnuts, but when it comes to the black walnut or filbert or some of these other things, they are still selling seedlings without labelling them as such. I think we should be on record against that practice, because it takes us five or six years, or ten years sometimes, to find out that we have been gypped, and it is so easy to gyp the public when you can't find out about it any sooner than that.

Mr. O'Rourke: I quite agree with Mr. Davidson that the nurserymen should state that a seedling is a seedling when it is a seedling. And I am sure Mr. Hirschi will corroborate that the American Association of Nurserymen is exerting all the influence they can to that end. Is that right, Mr. Hirschi?

Mr. Hirschi: Yes.

Mr. Bregger: I would like to ask, if planters for some years yet will have to rely on seedlings, is there a chance that from certain parents or certain varieties we can get a larger percentage of good seedlings than from others? How much has it been studied and is there a known result from the parent trees in the percent of what their seedlings can do?

Dr. Crane: I wish I could answer that one. It is a matter of time, to find out the seedling characteristics reproduced by a certain descendant. But we know that there is a difference in _uniformity_ of trees in the way they grow, but as far as bearing is concerned, and the type of nut produced, we haven't had enough time yet.

It's just like this: We have made selections for rootstocks in which we have selected trees that were good, strong and vigorous--the most vigorously growing trees that we have known about, and yet at the same time produced a small nut or medium-sized nut that we could use for the production of rootstocks. And we have made progress on that, and we have demonstrated that there is a very marked difference between the graftability or budability of seedlings from certain parent trees. We have demonstrated that some varieties are much easier to propagate than are others. But as for the proper combinations of stock and scion, we still haven't got enough data to recommend any. We know that there are differences, but it is going to take quite a long while, at least four or five years or more, before we know.

Now, there is just one other thing that comes up on propagation. We have found that if you bench-graft and make the graft into the transition zone between root and top just like the old method that the apple propagator used when he piece-root grafted and then plant deep, you can get a hundred per cent of the grafts to grow. In such cases the scion may root and the top will be on its own roots.

Well, there are a lot of these tricks to learn as time goes on. I don't think that we should worry too much about this graft union problem. We know that this Carr variety is a bear-cat. It is the one that gave us so much trouble. When we tried to propagate that one we had a real, nasty cat by the tail. But on the other hand, in answer to Dr. MacDaniels' question if we go out to Dr. J. Russell Smith's plantings up at Round Hill (Virginia), we can see a lot of the oldest grafted trees that I know of anywhere in the country, and the unions are just as smooth and just as slick as anyone would want to see. They are not 20 years old; I don't think there was ever a _mollissima_ chestnut grafted 20 years ago. The first grafting that I know of was about 15 years ago, maybe 18.

Mr. Stoke: In 1932.

Mr. R. C. Moore: Thomas Jefferson grafted European chestnuts.