Chestnut blight

“ Were it not for the blight which is now making practically a clean sweep of destruction over the eastern states, wherever the native chestnut is found, the American chestnut, Castanea dentata, would certainly be entitled to leading consideration as a highway, an ornamental or a nut producing tree. Unaffected by blight or other diseases, it is one of the largest-growing and most graceful species in the eastern United States. The European chestnut is nearly as susceptible to this blight as is the American species. ”

“ As you may be asked questions at the Northern Nut Growers' Association meeting at Rochester regarding chestnut blight work of the Office of Forest Pathology I am sending the following letter:
By means of short field trips and correspondents I am keeping up in a general way with the spread of the chestnut blight. The disease is steadily spreading southward and westward. Infections are now known in seven counties in Ohio and thirteen counties in North Carolina. There is every reason to expect that the disease will ultimately cover the range of the native chestnut and chinquapin. ”

“ The few surviving Asiatic chestnut seedlings were sickly looking, multi-stemmed, misshapen trees, heavily infected with twig blight and chestnut blight, and severely damaged by winter injury. But despite these heavy losses, a few plantations succeeded at least in part, and from these limited areas, together with an appraisal of the situations where some of the earlier planted chestnuts grew well, valuable information as to the site requirements of the Asiatic chestnut species was obtained. ”

“ 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. ”

“ Before the turn of the century, and even before chestnut blight had swept through our eastern forests, destroying one of our most valuable commercial timber trees, European and Asiatic chestnuts had been introduced. They made variable growth in the Gulf States, along the eastern seaboard from Florida to southern Maine, the southern half of Pennsylvania, southwestern Michigan, southeastern Iowa, down the Mississippi River Valley and on the Pacific Coast. These trees were grown for horticultural purposes, and for the most part, represented large-fruited varieties of Japanese chestnuts. ”

“ The problem in Italy is very serious, because they have something over a million acres of grafted chestnut orchards, all of which they are probably going to lose, and something like a million acres of coppice growth that is going to be damaged but not such a severe loss. In connection with the work in Italy I suggested the production of a movie film that could be shown to the Italian people showing the chestnut industry and also the chestnut blight. This was to be shown in different parts of Italy to arouse more interest in watching out for the disease. ”

“ We are having up in Ontario, beyond Toronto, a blight that has attacked the Lombardy poplar and that looks similar to the chestnut blight. I have been watching it for the last ten years and the tree seems to have at last outlived it. It dies down and then a little sprout comes out from the carcass.
The Chairman: Isn't that the poplar tree borer that always attacks the Lombardy?
Mr. Corsan: Oh no, it's very similar to the chestnut tree blight. We can grow chestnut trees all we like but no one has brains enough to grow them. The farmers grow pigs and things but don't bother with chestnut trees ”

“ Illinois claims prominence as a state where the commercial chestnut crop has been a profitable one for many years, beginning nearly three decades ago. Before chestnut blight, Endothia parasitica (Murrill) , killed the trees in the East, tons of nuts were gathered there and a considerable quantity marketed; these, however, were chiefly of the smaller native species and little attention was paid to the trees, most of which were wild. During the past few years some consideration has been given chestnut culture in the far West ”

“ Every foot of steep mountain land in some sections of Italy is said to be completely covered with chestnut trees. In my state, the weevil is the scourge of chestnuts; I had hoped that after the chestnut blight destroyed our native chestnuts, the Chinese and Japanese chestnuts would be free from that pest. Where it came from I do not know, unless it came from the chinkapin. West Virginia has chinkapins and these, being blight resistant, apparently have kept up the supply of weevils. Occasionally, shortly before the chestnuts begin to ripen, a few decay from some type of rot. ”

“ The chief aim of this breeding work, which has been carried on now without interruption since 1930, is to develop a tall timber type of chestnut by breeding the American species with the blight resistant but comparatively low-growing Japanese and Chinese chestnuts, Castanea crenata and C. mollissima, respectively. Practically all trees of our valuable American chestnut of any appreciable size have now been killed to the ground by the blight fungus, Endothia parasitica. ”

“ A few of these tenacious individuals are still sending up sprouts that may reach considerable size before they are again struck down.
I have had no serious trouble with blight in any of the named chestnut varieties, either Chinese or Japanese. I have lost some trees by its entrance into the seedling stock, but not many. My greatest headache has been sun-scald and winter killing, or to be more exact, "early spring" killing.
One of the juvenile characteristics of oriental chestnuts is the retention of their leaves all winter. They also grow in a rather sprangling way. ”

“ As a rule, however, the owners are not only willing but anxious to get rid of the infected trees, and our field men are given hearty support by individuals, granges and other organizations. The timber owners of Elk County had printed and posted an announcement that the chestnut blight had been found in the locality and warned the people to be on the look-out for it. ”

“ 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. ”

“ Rooting Chestnuts from Softwood Cuttings
ROGER W. PEASE, West Virginia Agricultural Experiment Station,
Morgantown, W. Va.
Some 15 or 20 years ago the West Virginia Agricultural Experiment Station undertook to develop, if possible, blight resistant chestnuts from American chestnut stock. With the passage of time the approach to the problem has changed. During the early days little thought was given to procedures for propagation, but recently the emphasis has shifted toward methods for propagation when and if there are found hardy, timber-type, blight-immune chestnuts of any species. ”

“ I am sure that as far as the production of good strains of blight-resistant chestnut, better strains of Chinese, and so on, that there are people in West Virginia who are more capable of telling you what has been done from a private viewpoint than anyone with the Conservation Commission, but we are interested in learning about it and producing it in large numbers for a game food, and, of course, if we are interested in distributing from our nursery over the state for that purpose, we are interested in producing better strains of blight-resisting chestnut as we go. ”

“ Crane: "The blight problem in the growing of chestnuts has often been stressed. I think you will have more loss from sunscald and root rot than you will from blight. Blight is a minor trouble with us. The Chinese chestnut naturally grows with a low head. It is a mistake to cut off the low branches on the trees until they attain some size, they can then be cut off."
Stoke: "Regarding the protection of nut trees against winter sun scald, I find that if you take ordinary aluminum paint and paint the south and southwest side of nut trees it will last for two years." ”

“ 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. ”

“ Some birds will take the blight north and our friends in Canada will finally have it, so cheer up, the worst is yet to come, but it will be a good many years.
MR. CORSAN: The blight has got to the extreme northern part of the chestnut growth, that is, to the top of Lake George. The chestnut doesn't go a quarter of a mile beyond Silver Bay.
DR. MORRIS: I have found chestnut trees in Quebec.
PROFESSOR NIELSON: Speaking of the range of nut trees, I have seen the hazelnut in the Saskatchewan several hundred miles north of the international boundary and at Edmonton, Alberta, Canada. ”

“ The chestnut is one of the most beautiful of our native nut trees. This tree has the blight in one of the earlier stages and it is shown here merely to call attention to the disease, because no discussion of the chestnut industry at the present time can be complete without at least calling attention to the seriousness of that blight. ”

“ The mycelium and the spores were healthy and were affecting the new trees in quite the same manner as the year before and as in other parts of the state.
The Chairman: The question of controlling blight after it has appeared is of very great consequence. Concerning any [Pg 52] commercial proposition with chestnuts the people are wide awake to the seriousness of the blight. They are afraid to go into growing chestnut orchards; they have had so many fake propositions in the past in pecan promotions that they are afraid of chestnuts and everything else. ”

“ Trees of the Chinese chestnut, Castanea mollissima, are quite resistant to the chestnut bark or blight disease. The heavy bearing of the trees together with the good quality of the nuts produced has stimulated planting of trees to replace those of the American species largely killed by that disease. Although a few horticultural varieties of Chinese chestnuts have been introduced and propagated, the great majority of the bearing trees are seedlings. In seedling plantings seldom do two trees produce nuts of the same size, color, and shape. ”

“ So far these have shown themselves to be quite tender varieties. I do not consider the chestnut worthwhile because of the constant threat that if a grove should be started it might soon have the blight in it.
I have several Chinese chestnut seedlings which are making a fairly good growth and in time may become productive trees.
We have one hybrid white oak which has an edible kernel but out of about one hundred nuts you might get one wholesome one free from weevils. The tree is very old and is rapidly declining. The nut is small but the tree is quite prolific. ”

“ In all my intensive work on the blight between 1907 and 1913 I cannot now recall a single instance where a chestnut sprout in a disease-ridden area ever reached a diameter of an inch or thereabouts before its existence was cut short by the blight; and yet today—a dozen years later—we are finding quite a number of living sprouts over two inches in diameter, and a few that are three, four, and even up to seven inches in diameter. Last Friday, August 29, I heard of a small chestnut tree in New Jersey that bore a few burs last year and which has a dozen or more this year. ”

“ Site and Soil.+ The most successful trees from the standpoint of growth and production were those growing on fertile, well drained soil in which moisture was plentiful. The Chinese chestnut tree appears to be shallow rooted and to require good growing conditions. Dry ridges were unfavorable for growth, and in bottom land the trees frequently were subjected to late spring freezing of tender shoots.
2. Blight injury to the trees and weevil damage to the nuts seemed to be the most serious enemies of chestnuts. Seedlings varied considerably in their resistance to blight. ”

“ The possibilities of growing trees from China, the mollissima, or hybrids of them, bids fair to place the chestnut industry so that we can contend with the blight. We probably will not have immune varieties, but those which are able to live with the blight. That, it seems to me, is a very important consideration, because chestnuts have always been an important nut in our eastern markets, and are important in the European markets as well. ”

“ We scarcely have a forest tree as useful, but if some natural handicap, not yet in sight, does not stay the spread of the blight fungus, our much valued chestnuts appear to be doomed. A few small colonies of diseased, but living sweet chestnut trees, numbering scarcely fifty, have been located in New York City parks and neighboring localities in Long Island, carrying infection at least eighteen years old, where the accompanying stands have completely vanished. ”