Chestnuts and the Introduction of Chestnut Blight
By Dr. Sandra L. Anagnostakis
Department of Plant Pathology and Ecology
The Connecticut Agricultural Experiment Station
123 Huntington Street
P. O. Box 1106
New Haven, CT 06504-1106
Telephone: (203) 974-8498 Fax: (203) 974-8502
American chestnut trees (Castanea dentata) were once so common in the Eastern United States that everyone who could get to the woods in the fall could count on nuts for roasting and for stuffing their Thanksgiving turkey. The wood was highly resistant to rot, and used extensively for poles, fencing, and building materials. An "imported" fungus disease was discovered in New York City in 1904, and within 50 years it had changed the appearance of our Eastern forests. The fungus, Cryphonectria (formerly Endothia) parasitica, enters wounds, grows in and under the bark, and eventually kills the cambium all the way around the twig, branch, or trunk. Everything distal to this "canker" then dies, sprouts are formed, and the process starts all over again. The fungus does not enter the "root collar" at the base of the tree, so sprout clumps survive today that are the remnants of the original trees. From the earliest discovery of the disease attempts were made to control it, but nothing worked. A major forest tree was reduced to a multiple-stemmed shrub (1). In 1912 the Plant Quarantine Act was passed to reduce the chances of such a catastrophe happening again (12).
Where did the chestnut blight fungus come from, and when did it come to the United States?
After the blight fungus was discovered here, plant explorer Frank Meyer found that it was present in both China and Japan, and that Asian trees were often very resistant to the disease and showed few symptoms when infected (10,11). This was taken as proof that Asian trees imported into the United States had brought the blight with them.
G. H. Powell wrote in 1900 (9) that Japanese chestnut trees (Castanea crenata) were first imported in 1876 by nurseryman S. B. Parsons of Flushing, New York (in the New York City borough of Queens, at the western end of Long Island). These were widely distributed, and two of them were planted and still survive in southern Connecticut. In 1882, William Parry in New Jersey imported 1,000 grafted Japanese chestnut trees. In the West, Luther Burbank planted a box of seeds sent by his collector from Japan in 1886. He subsequently had over 10,000 bearing trees growing in his Santa Rosa, California, nursery. Three of Burbank's selections were sold to Judge Coe in Connecticut, and then to J. H. Hale who propagated and sold them from his South Glastonbury, Connecticut, nursery.
Powell also reported that (by 1899) there were over 300 acres of chestnut trees near Philadelphia grafted with European and Japanese varieties, and that the Lovett Co. in Little Silver, New Jersey, (near the coast, about 15 miles south of Long Island) had also imported Japanese chestnut trees and were selling them by mail-order.
The 1899 and 1900 catalogues of the Mt. Hope Nursery (also known as Ellwanger and Barry, Rochester, New York) advertised Japanese, European, and American chestnut trees for sale (Table 1). In 1930, when Arthur Graves was looking for resistant trees for breeding, he found large Japanese chestnut trees on several estates on Long Island (New York) and in northern New Jersey. He said that many of them had been purchased around the turn of the century as "Japanese Giant" from a nursery near Rochester (3).
Any, or many of these importations of Japanese chestnut trees could have been the source of chestnut blight. In addition, the mail-order sales could have spread imported blight to all of the places were the trees were shipped.
Chinese chestnut trees (Castanea mollissima) were imported later. G. D. Brill went to China in 1900 and sent back chestnuts from Hankow and Ichang, and Lathrop and Fairchild sent seed back from Canton in 1902. Most of these were planted in the seed nursery in Bell, Maryland, but may have been another source of blight for the South.
The discovery of chestnut blight in the Bronx Zoo was described by Merkel (4) as follows: "...a few scattered cases which occurred [on American chestnut trees] during the summer of 1904. Early last June  this disease was noticed on so many widely scattered trees of all sizes that specimen branches and an appeal for information were sent to the USDA".
W. A. Murrill reported in 1906 that: "...the disease is known to occur also in New Jersey, Maryland, the District of Columbia, and Virginia."
Then, in 1908 Murrill said: "The disease is abundant in and about New York City, on Long Island, and in New Jersey, and is known to occur along the Hudson as far north as Poughkeepsie. Specimens have been sent in from Connecticut, Massachusetts and Maryland.
The disease was at first supposed to be confined to our native chestnut, but in the autumn of 1906 an affected branch was found upon one of the Japanese chestnut trees (Castanea crenata) growing in the open near the eastern boundary of the [New York Botanical] Garden."
Later in 1908 Murrill wrote: "The origin of the disease and the center of its distribution are still entirely unknown, while the area of its distribution is known very imperfectly as yet and can be determined accurately only by careful field explorations conducted by competent persons."
A Pennsylvania Department of Forestry report by John Mickleborough (6) listed distribution in 1909: "Its presence is known by the writer from personal examinations to extend from near the northern boundary of Maryland, through south eastern Pennsylvania, across New Jersey and New York. ...On Long Island the disease has spread for fifty or sixty miles with great rapidity, and is most prevalent and its ravages the most deadly...."
Since there was no blight in one area examined in Pennsylvania: "It was decided at once to make an Experiment Station at the Gap and to plant twenty-five Japanese chestnut trees and to start with one hundred grafts of the same species. ...Through the generosity of Mr. Isaac Hicks, a nurseryman at Westbury, Long Island, twenty-five Japanese chestnut trees were donated for the experiment and all the Japanese scions that could be used," probably bringing the blight with them.
Finally, when Haven Metcalf and J. Franklin Collins wrote their 1909 Bulletin they stated: "Even [in 1904] it is certain that [chestnut blight] had spread over Nassau County and Greater New York, and had found lodgment in the adjacent counties of Connecticut and New Jersey. No earlier observation than this is recorded, but it is evident that the disease, which would of necessity have made slow advance at first, must have been in this general locality for a number of years in order to have gained such a foothold by 1904. Conspicuous as it is, it is strange that the fungus causing this disease was not observed or collected by any mycologist until May,1905, when specimens were received from New Jersey by Mrs. F. W. Patterson, the Mycologist of the Bureau of Plant Industry. ...By August, 1907, specimens received by this Bureau showed that the disease had reached at least as far south as Trenton, N. J., and as far north as Poughkeepsie, N. Y., and was spread generally over Westchester and Nassau Counties, N. Y., Bergen County, N. J., and Fairfield County, Conn. ...reports have been received from points as remote as Cape Cod, Wellesley and Pittsfield, Mass.; Rochester and Shelter Island, N. Y., and Akron, Ohio. ...It can be quite confidently stated that the bark disease does not yet occur south of Virginia...
The theory...that the Japanese chestnuts were the original source of infection, has been strengthened by many facts...
While the disease has spread principally from the vicinity of New York City] there is much to indicate that it occurred at other points at an early date. Chester's Cytospora on a Japanese chestnut noted at Newark, Del., in 1902, may have been the bark disease. Observations by the junior writer indicate that this disease may have been present in an orchard in Bedford County, Va. as early as 1903, and that in Lancaster County, Pa., it probably was present as early as 1905..
It becomes more and more evident as this disease is studied that diseased nursery stock is the most important factor in its spread to distant points."
Can we tell now where the chestnut blight fungus first came in?
Any or all of those early Japanese imports could have carried it. Certainly, the Bronx Zoo was not responsible for bringing it in, even though their sharp-eyed grounds people first recognized the problem. People anxious to plant something new and different do not always notice problems on old and common plants. The catastrophe crept up on us, and left us a lesson that we continue to try to cope with today.
A biological control imported from Europe in 1972 allows us to keep American chestnut trees alive for breeding, and may be improved for better spread in the forest (1). Breeding projects are underway to combine the nut quality and timber form of American chestnuts with blight resistance of Asian chestnuts to produce trees for orchards and forests. We cannot undo the mistake of bringing chestnut blight into the United States, but perhaps understanding the history of this catastrophe will make us more cautious in the future.
Table 1. Chestnut Trees by Mail Order Showing Catalog, Date, Species Sold and Cost.
Reading Nursery, Jacob W. Manning, MA 1900: American $0.50-1.00
J. T. Lovett Co. Little Silver, NJ 1888 : 'Japan Giant' $0.75; Spanish $0.30; American $0.10-0.25; 'Numbo' $0.75
Storrs and Harrison, Painesville, OH 1888: American $0.50; 'Japan Giant' $0.50-0.75; Spanish $0.50
Shady Hill Nursery F.L. Temple, Cambridge (Somerville), MA 1888/1889: American $0.10-0.35
Highlands Nursery, H. P. Kelsey, Boston, MA 1899/1900: American $0.25
Biltmore Nursery, Biltmore, NC 1900/1901: American $0.15-0.50
Mt. Hope Nursery, Ellwanger and Barry, Rochester, NY 1897: C. Americana $0.50; C. Japonica $1.00; C. vesca $0.50
Elm City Nursery, New Haven, CT 1901: American $0.50-1.00; Spanish $0.25-1.00; 'Numbo' $1.50; Japanese $0.50-1.00
Fruitland Nurseries, P.J. Berckmans, Augusta, GA 1900: American $0.25-1.00; Spanish $0.25
Hale's Fruits, J.H. Hale, South Glastonbury, CT 1903: Japanese hybrids (from Luther Burbank) 'Coe', 'Hale', 'McFarland'
C.B. Hornor and Son, Mt. Holly, NJ 1897: American 0.$25-0.35; 'Numbo' $0.75; 'Paragon' $1.00-2.50
1. Anagnostakis, S. L. and B. Hillman. 1992. Evolution of the chestnut tree and its blight. Arnoldia 52:3-10.
2. Crane, H. L., C. A. Reed, and M. N. Wood. 1937. Nut Breeding (chestnut on pp. 827-835), Yearbook of Agriculture for 1937, pp. 827-889.
3. Graves, Arthur H. 1930. Progress toward the development of disease resistant strains of chestnut. Brooklyn Botanic Garden Record, 19:62-67.
4. Merkel, Hermann W. 1905. A deadly fungus on the American chestnut. N.Y. Zoological Society, 10th Annual Report, pp. 97-103.
5. Metcalf, Haven and J. Franklin Collins. 1909 The present status of the chestnut bark disease. USDA Bureau of Plant Industry Bulletin #141, part V.
6. Mickleborough, John. 1909. A report on the chestnut tree blight, the fungus Diaporthe parasitica, Murrill. Department of Forestry, The Commonwealth of Pennsylvania, Harrisburg.
7. Murrill, W. A. 1908a. The spread of the chestnut disease. Journal of the New York Botanical Garden 9:23-30.
8. Murrill, W. A. 1908b. The chestnut canker. Torreya 8:111-112.
9. Powell, G. H. 1900. The European and Japanese chestnuts in the Eastern United States. 11th Annual Report of the Delaware College Agricultural Experiment Station, pp. 101-135.
10. Shear, C. L. and N. E. Stevens 1913. The chestnut-blight parasite (Endothia parasitica) from China. Science 38:295-297.
11. Shear, C. L. and N. E. Stevens 1916. The discovery of the chestnut-blight parasite (Endothia parasitica) and other chestnut fungi in Japan. Science 43:173-176.
12. Waterworth, H. E. and G. A. White 1982. Plant introductions and quarantine: the need for both. Plant Disease 66:87-90.
The chestnut blight fungus was accidentally introduced into the U.S. on Japanese chestnut trees imported at the end of the 1800s. It was spread all over the range of our native chestnut trees by "mail order" as people bought chestnut trees from nurseries, and was spread locally by every creature that walked over the cankers. This led to the enactment of Plant Quarantine laws in the United States.