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American Chestnut

American Chestnut (Castanea dentata) was once a climax forest tree in the Oak-Chestnut dry woodlands of the eastern United States, but since the recognition of the Chestnut blight in1904 in New York, the entire forest population has been destroyed. Most of the intact, living trees in the wild were gone by the 1950s, and all that remains today are a few stump sprouts that still linger (attaining heights of about 25 feet before they succumb to the fungus). Breeding programs that have introduced resistance genes from Japanese and Chinese Chestnuts into moderately resistant strains of American Chestnut have met with some success, but the ultimate goal of large scale re-introduction into forests will not occur for some time, if ever.

In Ohio, the central counties of the state on a north-south line marked the most westward boundary of the American Chestnut habitat in the state. American Chestnut was predominately located in the eastern half of Ohio, where the soils are more acidic. Its nuts were a staple food of the Native Americans and pioneers, while its wood was harvested for the production of furniture, musical instruments, caskets, crates, and tannin. Dimensions of 80 feet tall by 60 feet wide were regularly obtained when it was located in the open. As a member of the Beech Family, it is related to the Oaks and the Beeches, in addition to other Chestnuts.

Planting Requirements

American Chestnut is still undergoing extensive breeding to allow its re-introduction as a tree that can not only survive the Chestnut blight fungus and yield large quantities of tasty nuts, but that can successfully compete in dry forests and re-establish itself as a climax forest tree. American Chestnuts found in the wild are primarily stump sprouts that will eventually die. Seedlings obtained from breeding programs are carefully planted and monitored under controlled conditions. From a historical (and perhaps future) perspective, the traditional American Chestnut prefers moist, deep, acidic soils in full sun (being shade tolerant in youth), but thrives in dry, rocky soils. It is found in zones 4 to 8.

Potential Problems

Chestnut blight (Endothia parasitica) is the only problem worth mentioning - any and all others pale by comparison. However, young trees from the few remaining stump sprouts (top photo) are resistant to the fungus for a number of years, even in some cases to the point of being able to bear fruits before becoming infected and dying.

Identifying Features 

Leaves of American Chestnut are alternate, elliptical to oblong, and with many prominent teeth that are narrow and point forward. The base of the leaf (at the point of attachment to the petiole) tends to be more narrow and angled sharply into the petiole than the corresponding wider leaf base of Chinese Chestnut.

Fall color is composed of shades of yellow, gold, and brown.

Leaves of American Chestnut may sometimes have stipules at the base of the petioles. While the leaves fall off in autumn, some of the stipules may remain attached to the twigs in winter.

The early summer flowers of American Chestnut occur in large clusters at the ends of the fully expanded new growth. The showy portions are the creamy, filamentous male flowers, which shed pollen on the nearby female flowers of this monoecious species.

A few of the female flowers give rise to the prickly fruits, which are actually several nuts enclosed in a spiny husk. This husk splits open in autumn, releasing the tasty chestnuts which are flattened on at least one side.

One difference between American Chestnut and Chinese Chestnut is the degree of pubescence on the twigs and buds, with American Chestnut having the slightest degree of hairiness on its winter twigs and buds, while Chinese Chestnut is much more fuzzy.

The branchlets and young bark of American Chestnut are shiny, olive-brown, and with prominent lenticels. Most trees do not reach an age where mature bark is seen, due to the lethal effects of the chestnut blight. Reportedly with increasing maturity, the dark gray bark of this tree develops deep fissures and prominent flat-topped ridges that are shiny.