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Plant a Tree Info - American Chestnut
American Chestnut
Castanea dentata, (Marsh.) Borkh.
Fagaceae
Species of Special Concern. American chestnut was once the most important tree species in much of the Eastern Deciduous Forest. Today, mature chestnuts are exceedingly rare within the original range of the species. Chestnuts remain only as sprouts and occasional seedlings, as mature trees outside the original native range, and a few dozen mature trees withing the original range. Chestnuts were devastated by chestnut blight, caused by Cryphonectria parasitica, a pathogen introduced from Asia in 1904. By the 1950s, chestnuts were wiped out as important forest trees. This is the greatest ecological disaster to occur in North America. Today, a few dedicated people are working to develop disease resistance in American chestnut. The American Chestnut Foundation is leading these efforts.
Species summary:
Chestnut occurred on the widest variety of sites, from well-drained alluvial soils on bottomlands to xeric ridgetops on acidic soils. It did not occur on limestone sites.
Meanings of names:
Genus name: Latin name for sweet chestnut
Species name: toothed
Common name: Chestnut is derived from the Middle English chesten, related to the Latin Castanea.
Species Distribution
North American Native? Yes
North American Status: Extremely rare as large trees within the original range. Root sprouts declining in frequency and vigor. Highly threatened with extinction. Note: not on the Endangered Species List because its near-demise preceded that act.
Range: s. Maine & S. Ontario s. to Alabama, w. to Missouri, Illinois; primarily Appalachian, absent from s. Coastal Plains.
Natural History Narrative:
Ecology: Chestnut was the most abundant tree on a wide range of mesic to xeric sites. On upland sites, it was commonly up to 70% of the stocking, though rarely forming pure stands. Its associates included mesic site species (northern red oak, sugar maple, basswood, cucumbertree, yellow-poplar) and xeric site species (scarlet oak, chestnut oak, hickories). The death of chestnut was sudden and dramatic. Whole stands died within a year or two after infection. This created enormous gaps in the canopy, at a time when forests were just beginning to recover from logging and land clearing throughout the Appalachians. These gaps were subsequently filled by a wide variety of species, but oaks were probably the principle beneficiaries.
Life History: Chestnuts flower in late spring. They are wind- and insect-pollinated. Seeds ripen in fall and are dispersed by small mammals. Chestnuts were not mast fruiting, bearing heavy seed crops every year. Germination occurred in seed caches the following spring. Growth was exceptionally fast: chestnut was among the fastest growing Appalachian hardwoods. Maximum longevity prior to chestnut blight was about 250 years. Today, only a few chestnuts live beyond 30 years. The root systems of chestnuts are extraordinarily persistent. When soil is disturbed in the Appalachians, chestnuts often sprout from these old root system, and these sprouts will persist for a few years, occasionally reproducing. When the bark begins to become rough, usually at about 4" DBH, the tree becomes susceptible and is killed by chestnut blight.
Interactions: Chestnut was extremely important in the ecology of Appalachian forests. Chestnut seeds are low in fat, containing mostly starch. Fruiting was annual, in contrast to the mast (irregular) fruiting habit of oaks and hickories. Chestnut was thus a very important source of nutrition for most eastern mammals, but did not provide adequate fat for overwintering. It is difficult to estimate the impact of the death of chestnut on wildlife populations, but it must have been profound. Chestnut is ectomycorrhizal; it is wind pollinated, with minor insect visitation.
Modern uses: Chestnut was a premier species, producing vast quantities of high value wood, and a nutritious, flavoral nut. Nuts were used for livestock feed as well as for human consumption. Old chestnut wood still comes on the market occasionally, and is very valuable.
Traditional uses: Chestnuts were an extremely important food for Native Americans. Unlike most other nut-producing trees, chestnuts produced reliably large crops annually. Chestnuts are very high in starch, moderately high in protein and very low in fat. Chestnuts were mainly a source of flour or meal used in making breads and soups, while other nut crops, such as hickory, were used for oil.
Chestnuts were also important to European settlers of the Appalachians until their demise. Many a family staved off starvation with chestnuts. Pigs were raised primarily on chestnuts, and were allowed to feed in the forests.
Native Americans used chestnut leaves and other parts for medicines, including cough remedies, heart medicine and other uses. The wood was an important building material and fuel wood, and the bark was used for dye.
Ornamental Considerations:
Ornamental uses: American chestnut cannot be used until resistant genotypes are available. As soon as resistant trees are available, they should be extensively planted as ornamentals on large sites where soil compaction is not a problem, particularly in naturalized plantings.
USDA Hardiness Zone: 4 to 8
Allergy potential: OPALS Male: 6
Allergy potential: OPALS Female: 6
Additional Species Data:
Form: Tree
Average mature height (ft.): 60-90ft
Maximum mature height (ft.): 120
Leaf Persistence: Deciduous
Shade Tolerance: Intermediate
Sexual expression: Monoecious
Pollinators: Beetles Wind Flies
Fruit: nuts (3) enclosed in a spiny cupule
Seeds: Nut
Seed Dormancy: internal
Seed Handling: Stratified nuts will germinate in a moist medium at temperatures of 60° F to 70° F for 28 days.
Mycorrhizae: ecto
Nitrogen Fixation? no
Leaf Type: simple
Leaflets: False
Leaflet Number: Minimum = 0; Maximum = 0; Usual = 0;
Leaflet size: length: 5-8in.; width: 1 3/4-3in.
Leaf Persistence: Deciduous
Leaf Size: length: 5-8in.; width: 1 3/4-3in.
Leaf Shape: oblong-lanceolate
Leaf Margin: coarsely serrate w/ sharp, glandular teeth
Leaf Apex: acuminate
Leaf base: cuneate
Leaf upper surface: lustrous yellow-green to dark green; glabrou
Leaf lower surface: glabrous
Petiole: 1/2in.
Leaf other descriptors: 1/2in.
Tree size: medium, 50-75 ft
Tree Shape: frequently trunk divided; broad, open crown w/ large, horizontal branches
Summer twig: rather stout; round, lustrous, glabrous, chestnut-brown
Leaf scar : oval-shaped w/ many bundle scars
Bundle scar: many
Pith: stellate
Winter twig surface texture: glabrous
Winter twig color: chestnut brown
Buds: terminal: absent; lateral: 1/4in, ovoid, acute, brown w/ 2-3 visible scales
Bark, young stems: gray-brown
Bark, older branches/tree: thick, gray-brown; furrowed w/ broad, flat ridges
Fruit:    Mature: nut encased in a spiny bur-like husk, husk interior densely wooly Immature:
Flowers: monoecious; appearing after leaves
All information on this page has been used with permission from TreeGuide.com.
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