Circular 247 March 1980 -e 4 4L 7 o - s N 3 NEW CHINESE CHESTNUTS AU-Cropper, AU-Leader, and AU-Homestead Their History and Production AGRICULTURAL EXPERIMENT STATION R. DENNIS ROUSE, DIRECTOR AUBURN UNIVERSITY AUBURN, ALABAMA CONTENTS Page INTRODUCTION ................. .......... .......... 3 4 7 8 IMPROVEMENT OF CHINESE CHESTNUT AT AUBURN UNIVERSITY .... AVAILABILITY OF TREES ......... .......................... LITERATURE CITED.................................... Photographs by R. E. Stevenson, Department of Research Information FIRST PRINTING 4M, MARCH 1980 Information contained herein is available to all persons without regard to race, color, or national origin. THREE NEW CHINESE CHESTNUTS: AU-CROPPER, AU-LEADER, and AU-HOMESTEAD-THEIR HISTORY and PRODUCTION HUBERT HARRIS*, J. D. NORTON**, and J. C. MOORE*** INTRODUCTION Borkh. was the most valuable species in the mixed hardwood forests of the Eastern United States about 75 years ago (3). American chestnut trees were fast growing and tall, often attaining heights of 100 feet (1,7). The decay-resistant wood was used extensively for construction, utility poles, railroad ties, fence posts, and rail fences. The excellent quality nuts were in abundant supply for man and wildlife each fall. Then, in approximately 30 years, almost all of these chestnut trees were destroyed by a blight caused by the fungus, Endothia parasiticaMurr., discovered in 1904 in the Zoological Garden of New York City (5). It apparently came into this country on Asiatic nursery stock about 1890. The disease spread rapidly throughout the natural range of the American chestnut. In areas where the American chestnut was once abundant, only a few persistent sprouts from the old stumps remain (5). The sprouts occasionally reach a trunk diameter of 6 to 8 inches and produce a few nuts before being killed back to the ground by the bark disease. The Chinese chestnut, (Castanea mollissima) Blume was introduced into the United States in 1907 by the United States Department of Agriculture (2) with small plantings initially made over a wide area. Its resistance to the chestnut blight was responsible for the interest in planting the Chinese chestnut. *Associate Professor, Emeritus, Department of Horticulture **Professor, Department of Horticulture ***Assistant Professor, Department of Horticulture, Deceased T HE AMERICAN CHESTNUT, Castanea dentata (Marsh) Progress has been made in breeding and selection for improved varieties, and this appears to offer the greatest opportunity for further improvement of this crop (3). The Chinese chestnut is resistant to blight and the best seedlings and varieties bear abundant crops annually. Nuts of the better selections are excellent in quality. Annual yields of 50 to 70 pounds of nuts per tree, from 10 to 12 year old trees, have been reported (3). Yields greater than 130 lb. per tree have been obtained from mature Chinese chestnut trees at Auburn (7). At present day prices, a gross income of $1,320 to $2,850 per acre should be received for an orchard in full production based on data of Davidson and Reed (4). The tree grows well throughout the southern part of the natural range of the American chestnut and southward to the Gulf Coast (6). IMPROVEMENT OF CHINESE CHESTNUT AT AUBURN UNIVERSITY A planting of Chinese chestnuts has been growing at the Auburn University Agricultural Experiment Station since 1935 with attention being given to seedling evaluation, propagation, and utilization. The first planting was established at the United States Department of Agriculture Hillculture Farm under the supervision of J.C. Moore. The Hillculture Farm became the Mainstation Horticulture Farm when expansion of the University required this relocation. Three blight resistant seedlings selected for nut appearance, size, and quality have been released. They are the product of controlled mass pollination and selection from two generations of approximately 2,000 seedlings. TABLE 1. YIELD AND NUT SIZE OF CHINESE CHESTNUTS, AUBURN, ALABAMA, 1967-19751 Cultivar Black Beauty .. Date Seed Top Nut planted worked size 1935 - Yield by years 1967 1968 1969 1970 1971 1974 1975 No./Lb. Lb. 41 - Lb. 112.9 - Lb. 55.5 39.0 19.3 - Lb. 45.3 25.9 2.8 Lb. - Lb. - Lb. 88.2 48.0 46.8 AU-Cropper .. AU-Cropper ... 2 AU-Leader ... AU-Leader .... 1935 1954 1954 1954 38 41 35 34 107.0 - 70.6 89.3 71.6 130.9 79.4 132.0 60.6 65.2 47.5 36.1 27.0 25.9 1965 1967 AU-Homestead AU-Homestead 1954 1954 1965 39 41 42.5 8.4 50.4 10.1 71.0 11.3 62.5 8.9 88.3 65.3 25.6 24.5 98.0 25.3 1 Records are on single trees. Maintenance has been limited to occasional mowing. Nuts removed by squirrels and individuals not recorded. 2 Original tree of AU-Leader was top worked to another seedling by mistake. Therefore, a delay in production resulted. [4] lldte( as seed lingI 35-A\At -Cropp)1er w\as sel ecteldl an1d -4-4. It collsistently produles highl \ ielcL5 f ('\(Icllt (julldlt\ Jnlts (tadle 1). ThIII its are~ (Iu jin sire to colllliul nmarket cestnults, the nuIbI perll&l1) polilld is 38 (tal) I). Color oIf th anits is (lark c1hocolate broxxn ((,ray ish hro\\ in 7.5 YB 3/2 )1 overi- the apex (igur e 1 ). They are 21 os s\ did attracti \ e. Tai o to three nutts are p~resenlt init alildul irge btir. N its separ ate readil\ fromi the hIIrr upon01 maltur1ity ad opeingl of the 1urr (tahd ). .1t,-Leadier its selected aw e\ alutd( as seollin( 5-1-1.3. It tl also)produles~ highi \ ids oftcxeclleit (jIlal its nuts. The tnuts of' AU-Leader are largter thm those of AU.-(Cropp1er altd AUIlottstedl (talte 1). Theo umbetltr of' tnuts pcrF floild ofl AU.- lainl w~ithl tin gray 1)!1lescence X\ 10( isnol(l proml~inen~t mical f~ 4 ~ , FIG. 1. AU-Cropper (Liang Chang Li). is .35. Nuit (c010r ([ark chocoNlate b~roO\\ is tra\isli brown r I 7.5 YR :3/2) o'. erdlin withi thin trnax ish brownI publesceee w\hich is more proinent near the apeN (liopper, A\U-Leadler, a11d AU.-H omiesteadf shou11(11) ax ailale front nurseries for pl1antliI( in tile itter of 1980-1981. A l imitedl jiiaitit% of wox fo(1hr p)ropagationu may be seecured front f.D. Norton, IDepartmeutt of Hlorticuiltiure, Aiibiiru Unlxcisit\ , Aibirt. AL 368:30) [71 LITERATURE CITED (1) (2) (3) L. 1978. The American Chestnut: New Hope for a Fallen Giant. Conn. Agr. Exp. Sta. Bull. 777. ANONYMOUS. 1965. Chestnut Blight and Resistant Chestnuts. U.S. Dept. of Agr. Farmers Bull. 2068, slightly revised (Supersedes Farmers Bull. 1641). ANAGNOSTAKIS, SANDRA CRANE H. L., C. A. REED, AND M. N. WOOD. 1937. Nut Breeding. U.S. (4) (5) (6) (7) (8) Dept. of Agriculture Yearbook. pp. 826-889. DAVIDSON, J. C. AND C. A. REED. 1954. The Improved Nut Trees of North America and How to Grow Them. Devin-Adair Comp. New York, 404 p. GRAVATT, G. F. AND L. S. GILL. 1930. Chestnut blight. U. S. Dept. of Agr. Farmers Bull. 1641. HARDY, MAX B. 1948. Chestnut Growing in the Southeast. Northern Nut Growers Association. pp. 41-50. HARRIS, HUBERT. 1975. Chinese Chestnuts. Annual Progress Report, Department of Horticulture, Auburn Univ. (Ala.) Agr. Exp. Sta. JAYNES, RICHARD A. AND A. H. GRAVES. 1963. Connecticut Hybrid Chestnuts and Their Culture. Conn. Agr. Exp. Sta. Bull. 657. [8]