The buckeye is a distinctive seed, often recognized for its smooth, dark appearance. This leads to questions about the tree that produces it.
The Buckeye Tree
The tree responsible for these seeds belongs to the Aesculus genus, commonly known as buckeyes and horse chestnuts. Among these, the Ohio Buckeye (Aesculus glabra) is a prominent North American species. This deciduous tree reaches heights of 20 to 60 feet and develops a rounded or oval crown. Its bark is gray and can be corky or become scaly and fissured with age.
Ohio Buckeyes are identified by their palmate compound leaves, which usually consist of five palmate leaflets. These leaflets are 3 to 6.5 inches long and have finely toothed margins. In spring, the tree produces upright clusters of yellow-green flowers with stamens extending beyond the petals. The Ohio Buckeye is native to the Midwestern and Great Plains regions of the United States, thriving in moist, well-drained soils, often found along streambanks and in woodlands.
Buckeyes: Appearance and Toxicity
The “buckeye” is the tree’s seed, enclosed within a leathery, often warty or spiny husk that splits open when mature. The seed itself is shiny, dark brown, and distinctive, featuring a lighter tan or white “eye” or scar where it was attached inside the husk. This resemblance to a deer’s eye is how the seed, and the tree, earned its name. Buckeye seeds are toxic.
All parts of the buckeye tree, including the seeds, leaves, and bark, contain toxic compounds such as glycosides and saponins. Ingestion by humans or animals can lead to symptoms like nausea, vomiting, diarrhea, abdominal pain, muscle weakness, and, in more severe cases, tremors or paralysis. It is important to handle buckeyes with care and keep them away from children and pets to prevent accidental ingestion. If ingestion is suspected, immediate medical or veterinary attention is recommended.
Distinguishing Buckeyes from Look-Alikes
Buckeyes are often confused with horse chestnuts, both of which belong to the Aesculus genus, but key differences exist. Ohio Buckeye leaves typically have five leaflets, while common horse chestnut leaves usually have seven. The fruit husks of Ohio Buckeyes are generally warty or slightly spiny, whereas common horse chestnut husks can be more strongly spiny. Horse chestnut seeds tend to be larger and sometimes flatter on one side compared to buckeye seeds.
Buckeyes and horse chestnuts should be distinguished from true chestnuts (Castanea genus), which produce edible nuts. True chestnuts have very spiny, burr-like husks and their leaves are simple, with toothed edges, rather than the palmate compound leaves of buckeyes and horse chestnuts. Unlike true chestnuts, all buckeye and horse chestnut seeds are toxic.