Chestnut identification can be difficult for a variety of reasons. For those not trained in botany or forestry, there are many trees in the forest which are difficult to tell apart. Even for those with some specialized training, the American chestnut has not been around for some time and is thus no longer taught in many silvics or dendrology courses. More importantly, even for those with advanced training, the many species of chestnut hybridize freely (especially American and Chinese) and do not exhibit clear traits of any one species. Many hybrid cultivars also exist as part of the nursery trade which further compounds identification problems.
There are four common species found in the eastern United States, but only one is native. The others have been imported for horticultural purposes. These species include:
American chestnut (Castanea dentata)
European chestnut (Castanea sativa)
Japanese chestnut (Castanea crenata)
Chinese chestnut (Castanea mollissima)
As a general rule, if you find a chestnut growing in an urban, suburban, or commercial setting it is probably NOT an American chestnut (the only native species). American chestnuts in Ohio are most likely to be found in the unglaciated portion of the State (South and East) under naturally forested conditions.
There are many resources available for chestnut identification which we will post here (soon). An excellent botanical key, providing both general and quick keys, to the different species of chestnut is provided by R.H. Zander of the Missouri Botanical Garden: Chestnut Key.
Shown below are pictures of the male (staminate) inflorescenes, female (pistillate) flowers, fruits, leaves, and shoots.
Picture illustrating the female (pistillate) flowers in white. Below them are two fertilized flowers with newly set fruits which have not yet matured to form the characteristic bur and nuts. Early June.
Picture on forest floor showing the characteristic brown foliage of chestnut in the autumn and a mature bur which has opened to release its nuts. Late September.
Picture showing a characteristic reddish brown shoot, green almost translucent leaves, and white catkins (staminate inflorescence) at the base of the newly formed shoot. NOTE: leaves and twigs of American chestnut are virtually hairless.
If you think you have an American chestnut and wish to have it verified, please fill out the Ohio Chestnut Tree Inventory Form and mail to the address indicated with a specimen enclosed.