The Buckeye tree (Aesculus glabra) is a broadleaf tree that is famous in some areas of the country.
But, many people wonder is there only one type of Buckeye, and what makes this tree so memorable?
And, where did the name “buckeye” come from?
This complete guide provides all the information you need to know about how to identify a Buckeye tree, how to recognize it’s nuts and flowers and why the Ohio Buckeye is toxic.
Ohio Buckeye, American Buckeye, Fetid Buckeye, and Stinking Buckeye (Nature's Rubber Ball Dispenser)
(Aesculus glabra)
- Characteristics: Small to medium-sized tree with low branches and a wide, oval crown
- Family: Sapindaceae
- Genus: Aesculus
- Leaf: Palmately compound
- Bark: Grayish-brown, scaly
- Seed: Known as Buckeyes or conkers
- Blossoms: Showy, white to yellow-green flowers in spring
- Fruit: Capsules filled with Buckeye seeds, which are sadly inedible
- Native Habitat: Eastern and Central North America, with a soft spot for Ohio
- Height: 50-75 Feet
- Canopy: Spreading
- Type: Deciduous
IUCN Red List of Threatened Species Ranking
Least Concern
Image Credit: Daderot26
How To Identify Buckeye Tree
The Buckeye is among the more common trees, a deciduous native to the Eastern United States. It is the official Ohio state tree and is particularly common there.
More specifically, within the state, it is concentrated in Western Ohio as an understory tree. In the below paragraphs, we discuss some of the ways on how to identify the Buckeye Tree.
You can recognize the Buckeye by its palmately compound leaves, which basically means having more than three leaflets attached to the “petiole” (the part from where the leaflets emerge). The bell-shaped flowers that are also distinctive.
The Buckeye is often the first tree to throw out its leaflets after a long Midwestern Winter.1
Buckeye Tree Leaves
Buckeye leaf have 5-7 leaflets each 3-6 inches long, and with a toothed margin.
Buckeye Tree Flower
Flowers are bright yellow-green, shaped like a bell, with distinctive patterns of yellow, orange, and red at the base.2
Buckeye Tree Seeds
Buckeye fruits and tree seeds, from which the name is derived (“the Buck’s eye”) have a capsule with one or two shiny, dark brown seeds that have traditionally been carried to convey good luck and protect from rheumatism.1
The capsule opens up when ripe.
Buckeye Tree Bark
Buckeye Tree bark is smooth when young, but rough and scaly as it ages, appearing gray-brown in color.3
Buckeye Distribution
These fine Buckeye Trees are usually found in the East-Central United States, particularly in Western Pennsylvania, Ohio, and Michigan, as well as Illinois, Tennessee, Alabama, and occasionally, in Georgia. It can thus be said generally, that the Buckeye distribution is wide.
The Ohio Buckeye is found in 28 states.4 Ohio has the nation’s biggest population of Buckeyes,5 most prevalent in the state’s southern and eastern regions, with substantial concentrations in the Appalachian foothills.
Statewide distribution varies. In Indiana, for example, the Ohio Buckeye is found mostly in the state’s south, where the environment is more suitable.
The Buckeye in Illinois is largely distributed in the eastern regions, in steep terrain and well-drained soils.
Buckeyes tend to like “shady, moist areas.”
Buckeye Tree Facts
Here are some Buckeye Tree facts for you: Buckeye are the state tree and cultural icon of Ohio. In some places, you are legally not allowed to disturb a Buckeye tree!
There is a famous trail in Ohio, called the Buckeye Trail. Some of the trail destinations include Cuyahoga Valley National Park, Tappan Lake, Wayne National Forest, and East Fork Estate Park.6
Are Buckeyes Poisonous?
Why yes, they are!
Buckeyes are in fact poisonous. Very much so.
There isn’t a part of the plant that is not highly toxic to people and livestock, although, notably, not to squirrels who have been known to eat the seeds.1
The active agents is glycoside aesculin and saponin aescin, which cause weakness in the muscles, dilated pupils, vomiting, diarrhea, depression, and eventually paralysis.1
Despite looking like tasty chestnuts, Buckeyes contain a toxic compound called aesculin.10 If you put one in your mouth, it will feel like your tongue is trapped in a sewing machine.
Buckeye in Cultural and Historical Context
As mentioned earlier, the Buckeye is the state tree of Ohio, and many businesses, historical places, geographical locations, and cultural icons are named after the Buckeye. Ohio residents are sometimes called Buckeyes.
There are obviously deep Buckeye cultural and historical contexts intertwined with the tree.
In 1953 the tree was declared the state tree of Ohio. The term Buckeye was coined way back in settler times because the nut is dark brown with a lighter spot, similar to a deer’s eye, thus “buck-eye”.
Buckeye nut was used medicinally by Native Americans and settlers alike. Native tribes would use the nuts for cuts, and rashes, and to heal a wide array of diseases, often acting as an opioid.
More recently, there seems to be a suggestion that it may be a treatment for arthritis pain and rheumatism. Early settlers liked the Buckeye wood which was easy to work with and light.
Buckeye trays, logs, cradles, spoons, and all kinds of other household paraphernalia were made by settlers. Even today, the Buckeye is used to make artificial limbs.
Ohio State University sports teams are known as Buckeyes, as is their mascot. Other culturally significant uses of the Buckeye are in literary and artistic works, such as “the Buckeye Song” by W.W. Armstrong and “the Buckeye Tree” by C.A. Bowles.
What Is the Difference Between California Buckeye and Ohio Buckeye?
Califonia Buckeyes (Aesculus californica) are a distinct species different from the Ohio Buckeye.14 California Buckeyes are endemic to California, while Ohio Buckeyes remain endemic to the Eastern United States.
California Buckeyes have more slender leaves, a generally more open canopy, and attractive aromatic clusters of pinkish or white flowers, while Ohio Buckeyes have greenish-yellow flowers.
Western cousins also come with a customary warning from USDA that all parts are toxic, just like their eastern cousins.
The Buckeye Tree and Environmental Sustainability
Quite obviously, as a tree the Buckeye sequesters carbon dioxide. It nourishes local fauna by providing food to its native environment.
Shade helps with urban heat and energy expenditures, all of which go towards the Buckeye Tree’s environmental sustainability.
The tree is also a source of sustainable medicine going back to Native Americans and early settlers, as described in the section on culture and history above.
Buckeye Planting Tips and Growing Zones
Below are some sections where we discuss Buckeye planting tips and growing zones.
Buckeye Tree Growing Zone (Growing Zones for Buckeye Tree: Where To Grow)
In regards to Buckeye Tree growing zones, Buckeye Trees prefer to vacation in USDA hardiness zones 3 to 7,7 where they can enjoy a fabulous mix of temperate weather and fashion-forward winters.
Planting Tips for Buckeye Tree
Find a spot with well-drained soil and plenty of room to spread its canopy (it’s a little claustrophobic).
The tree grows fastest when it is rather isolated, along the bank of a stream or in other typically wet locales.
Spring or fall is the perfect time to plant. Buckeye Trees love a good seasonal event.
How Far Apart To Plant Buckeye Tree
As regards how far apart to plant a Buckeye Tree, Buckeyes value their personal space. So, it’s advised by the Farmer’s Almanac to plant them at least 20-30 feet apart.
To allow them full growth, perhaps 50×50 feet.
Growing Buckeye Tree From a Seed
To grow a Buckeye from seed, start with fresh seeds in the fall, from the healthiest tree you can find. Soak them in water for 24 hours.
This will help soften the outer shell. Now plant the seeds in lightly wet potting soil (don’t waterlog) and cover them with a plastic bag or wrap them to retain moisture.8
You aren’t done yet – the last step is to put it in a warm, bright spot and wait for it to grow, transplant it as the plant grows, in progressively bigger pots.
Growing a Buckeye Tree From a Cutting
You can grow a Buckeye Tree from cuttings, but its a bit harder. Late spring or early summer are best for cuttings, when the tree is actively growing.
Your cutting should be 6 inches long and made with a 45-degree angle cut.
Remove the leaves from the bottom half of the cutting and put some rooting hormone. You could try make a little greenhouse or use plastic to cover to retain moisture.
Growing a Buckeye Tree From a Seedling
It is possible to propagate Ohio Buckeye Tree through cuttings, but perhaps more difficult than from seed. Cuttings should be taken in late spring or early summer when the tree is actively growing and new growth is still delicate.
Select a healthy branch at least 6 inches long and make a clean 45-degree angle cut using a sharp, clean pair of pruning shears. Remove the leaves from the bottom half of the cutting and coat the cut end with the rooting hormone to promote root growth.
To make a little greenhouse, place the cutting in a container filled with damp potting soil and cover it with plastic wrap or a plastic bag.
Next, remove leaves from the bottom half of the cutting and coat the cut end with the rooting hormone. If you want to make a little greenhouse, place the cutting in a container filled with damp potting soil and cover it with plastic wrap or a plastic bag.
Place the container somewhere warm and sunny, but out of direct sunlight.
As was the case with seeding, the soil should not be beyond moist, and spritz the cutting regularly. After a few weeks, gently pull to see if it has rooted; if it resists, you’re all good.
Now transplant as needed.
Best Growing Conditions for Buckeye Tree
Buckeyes like a pH of 6-7.5 and like many other trees of its kind, well-drained soil. While sun exposure of about 6 hours is good for them, but still prefer some shade when it gets too hot.
Buckeyes are pretty resilient against droughts, but regular irrigation tends to go well with the watering needs for Buckeye Tree plants. One critical aspect is to give them enough space to grow to their full size of 50×50 feet.
Buckeye Tree Disease Prevention
It is important to take steps for Buckeye Tree disease prevention if you wish to preserve Buckeyes are heir to various maladies, such as leaf blotch, anthracnose, leaf scorch, and powdery mildew. All of these interrupt photosynthesis, weakening the tree, even if it only affects a small percentage of the tree’s leaves.9
After a few years, any of these diseases can wipe out all of the leaves, reduce growth, and weaken the tree so that other pests can move in.
It is important to take steps for Buckeye Tree disease prevention if you wish to preserve your trees.
One step to preserve an affected tree is to dispose of fallen leaves before the snow starts falling. On the ground, leaf diseases can survive during the Winter and return to harass the tree during the next growing season.
Another step is to keep the leaves dry insofar as that is possible. It is not recommended to use sprinklers and to generally avoid splashing water on the leaves.
A third step for avoiding tree diseases is to keep a layer of mulch around the base of the tree.
What Are Some Potential Problems With the Buckeye Tree?
Leaf blotch, a disease that can severely harm or kill a tree, can be a problem for Buckeyes.
Anthracnose and powdery mildew are common, as well as susceptibility to pests such as Japanese beetles, borers, and bagworms.
When water constrained or exposed to extreme conditions, leaf scorch may also be an issue.13 It is thought that air pollution may have more to do with the Buckeye’s partial defoliation rather than the typical culprits of heat or drought.1
How To Stop Buckeye Tree Disease
It is important to know how to stop a Buckeye Tree disease. Treatment and prevention of Buckeye Tree disease can vary, and professional advice should be sought from an arborist.
However, here is some general advice:
- Prevention is better than cure, so a healthy tree should be the first aim to protect against disease: sunshine, water, and nutrients
- Remove infected branches, to stop the spread of the disease, but in some cases, it may be better to remove the tree itself to prevent the disease from spreading
- Prevent borers and leaf miners, and other pests from infecting your trees, so as not to weaken the tree, and give diseases a scope to attack
- Fungicides. Sometimes terrible chemicals can be man’s best friend.
Make sure to choose wisely and specifically for the disease, and preferably consult professional advice.
(Note: if a tree is already suffering from leaf spots, a fungicide may not help. Unless the tree has lost all its leaves for several consecutive years, a fungicide will not be necessary.9) - When all else fails, consult an arborist, or do so before losing precious time.
Natural Pest Control for Buckeye Tree
Natural pest control for Buckeye can be achieved simply by allowing ladybugs and lacewings to shack up on the trees. These in turn feed on aphids and scale insects.
Neem oil, which is derived from the Neem Tree can also act as a natural pesticide, while other approaches include home remedies such as garlic, hot pepper, soap, etc as pest deterrents.
Companion Plants for Growing Buckeye Tree
Companion plants for growing Buckeye Tree include plants such as chives and marigolds; these can help by attracting “good” insects and pushing away the bad ones.
Endemic to several eastern states and the state tree of Ohio, the American Buckeye or Ohio Buckeye, is a culturally important tree of the United States. The tree has evolved to a variety of environmental conditions and soil types.
They can also grow in both full sun and moderate shade, though they prefer partial shade.
The Buckeye is found throughout the Eastern United States, with substantial populations in Ohio, Indiana, and Illinois. The Ohio Buckeye’s range varies according to the local climate and geography.
Buckeye provided those early settlers with a resource that helped them survive, both for its wood, firewood, and medicinal purposes, as it helped the Native Americans before them.
Understanding the beauty and the dangers of the Buckeye tree can help you decide if you’d like to risk having this tree grace your garden.
Frequently Asked Questions About Buckeye Tree
Are Ohio Buckeyes Poisonous To Bees?
While highly toxic to most animals, the Buckeye is not toxic to most insects, including bees.11 Bees and hummingbirds,12 among other such critters love the Buckeye honey, and flowery bits.
How Long It Takes To Grow Buckeye Tree?
Ohio Buckeyes are moderate growers, averaging 1-2 feet annually, and take 5-20 years for maturity, all dependent on varied growth factors. Buckeyes have similar growth to Sugar Maples, Dogwoods, and American Beeches, but grow more slowly compared to shade trees such as White Oaks, Silver Maples, and Red Maples.
Are There Any Special Cultivars for Buckeye Trees?
Early Glow™, although sounds like an adult-use product is an Ohio Buckeye cultivar. Developers claim it has better resistance to leaf blotch, powdery mildew, and leaf scorch. It’s targeting ornamental needs with a claimed reliable red fall color, and low fruit production to keep away the squirrels.
Can Squirrels Eat Buckeye Nuts?
Though this tree is poisonous in every possible way, squirrels somehow manage to eat the nuts, and survive.
How Does the Red Buckeye Compare With the Ohio Buckeye?
Smaller cousin, bit shorter, toxic but less toxic than the Ohio, and like the name, has red flowers.15
What Are the Differences Between American Chestnut and Ohio Buckeye?
American Chestnut (Castanea dentata),16 larger than the Ohio Buckeyes, growing to 100 feet tall and 70 feet wide. The Chestnuts are edible to humans, unlike the Buckeye.
What Are the Differences Between Hazelnut Tree and Ohio Buckeye?
The Hazelnut Tree (Corylus avellana) is smaller,17 at 20 feet, but they has the advantage of producing edible nuts.
What Are the Differences Between Cashew Tree and Ohio Buckeye?
The Cashew Tree (Anacardium occidentale) is native to South America and produces a Cashew Apple, and a Cashew nut, both of which are edible, with the Cashew nut being popular worldwide.18
What Are the Differences Between Black Walnut Tree and Ohio Buckeye?
Black Walnut Tree (Juglans nigra) is much taller than the Buckeye,19 reaching 100 feet, and produces a round, hard nut that is edible, unlike the poisonous nut of the Buckeye.
Why Are Some People Called Buckeyes?
Natives of Ohio are often called Buckeyes, as the state and its citizens have adopted the Buckeye Tree as their identity, as well as their most well-known college football team. Thus if Ohioans go to another state, they can often identify as Buckeyes, or be called Buckeyes by outsiders.
Are Ohio Buckeyes Winter Resistant?
To a good extent yes, but everything is relative; the USDA considers them good for zones 4-7.
How Do Peanuts Grow?
Peanuts can be grown by first planting seeds in well-drained soil with a pH of 5.8-6.2.20 Peanuts produce yellow flowers, which fall down, and the remaining peg grows into the soil producing peanuts underground that are harvested by digging them up; this answers the question “how do peanuts grow?”
How Do Pistachios Grow?
Pistachio Trees thrive best in hot, dry summers and cold winters, preferring soils that drain well and have a pH of 7.5-8.5.
Additionally, knowing how do pistachios grow will tell you that Pistachio Trees are preferably cultivated from grafted seedlings and often planted in rows, with 15-20 feet between trees.21
How Much Sunlight Does Buckeye Tree Need Each Day?
As for how much sunlight a Buckeye Tree needs each day, the trees enjoy partial to full sunlight for about 6 hours per day.
What Is the Best Season on When To Plant Buckeye Tree for the Best Yield?
Regarding when to plant Buckeye Tree, for the best yield, plant your Buckeye saplings in early spring or fall. Fall is considered the best as the tree can avoid the hard summer, and develop its root system better.
How Much Carbon Does Buckeye Tree Sequester?
Regarding how much carbon the Buckeye Tree sequesters, on average, a mature Buckeye Tree can sequester about 48 pounds of CO2 per year. Not too shabby.
What Are the Common Pests of the Buckeye Tree?
As for common pests of the Buckeye Tree, the Buckeye has a few uninvited guests, including leaf miners, scale insects, and borers. But hey, who doesn’t have some pesky friends hanging around?
Is the Buckeye Tree an Ornamental Tree or a Landscape Tree?
Because of its smaller stature, Buckeyes may not be the right tree as a street tree or near homes. On the other hand, they can make a relatively manageable ornamental tree, with squirrels eating their (toxic) nuts, ornamental and vivid flowers, and exquisite branching.
References
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2Wikipedia. (2023, March 20). Aesculus glabra. Wikipedia. Retrieved April 19, 2023, from <https://en.wikipedia.org/wiki/Aesculus_glabra>
3Arbor Day. (2023). Buckeye. Arbor Day Foundation. Retrieved April 19, 2023, from <https://www.arborday.org/programs/nationaltree/Buckeye.cfm>
4Department of Agriculture. (2023). General Information. United States Department of Agriculture. Retrieved April 19, 2023, from <https://plants.usda.gov/home/plantProfile?symbol=AEG>
5Ohio Department of Natural Resources. (2023). OHIO BUCKEYE. Ohio Department of Natural Resources. Retrieved April 19, 2023, from <https://ohiodnr.gov/discover-and-learn/plants-trees/broad-leaf-trees/ohio-buckeye-aesculus-glabra>
6Ohio Department of Natural Resources. (2023). The Buckeye Trail Story. Ohio Department of Natural Resources. Retrieved April 19, 2023, from <https://ohiodnr.gov/static/documents/parks/parkmaps/btamapbrochurefinal.pdf>
7IOWA STATE UNIVERSITY. (2023). Ohio Buckeye. IOWA STATE UNIVERSITY. Retrieved April 19, 2023, from <https://naturalresources.extension.iastate.edu/forestry/iowa_trees/trees/ohio_Buckeye.html>
8Hogan, M. (2022, September 10). Gardening: Want to grow your own Ohio buckeye tree? Here are 7 things you need to know. The Columbus Dispatch. Retrieved April 19, 2023, from <https://www.dispatch.com/story/lifestyle/home-garden/2022/09/10/seven-things-to-know-about-growing-an-ohio-buckeye-tree/65466906007/>
9Grabowski, M. (2018). Leaf spot diseases of trees and shrubs. University of Minnesota Extension. Retrieved April 19, 2023, from <https://extension.umn.edu/plant-diseases/leaf-spot-diseases-trees-and-shrubs>
10Knebusch, K. (2015, May 15). Ohio State Fans: 7 Things to Know About Growing an Ohio Buckeye Tree. CFAES. Retrieved April 19, 2023, from <https://cfaes.osu.edu/news/articles/ohio-state-fans-7-things-know-about-growing-ohio-Buckeye-tree>
11Garvey, K. K. (2014, March 26). Eye on the Buckeye. BUG SQUAD. Retrieved April 19, 2023, from <https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=13272>
12MISSOURI DEPARTMENT OF CONSERVATION. (2023). Ohio Buckeye. MISSOURI DEPARTMENT OF CONSERVATION. Retrieved April 19, 2023, from <https://mdc.mo.gov/discover-nature/field-guide/ohio-buckeye>
13Forest ReLeaf OF MISSOURI. (2023). OHIO BUCKEYE (AESCULUS GLABRA). Forest. Retrieved April 19, 2023, from <https://moreleaf.org/product/ohio-buckeye-aesculus-glabra/>
14Anderson, M.K.,W. Roderick, and M.L. Smither-Kopperl. (2019, September). CALIFORNIA BUCKEYE. USDA. Retrieved April 19, 2023, from <https://www.nrcs.usda.gov/plantmaterials/capmcpg13492.pdf>
15MISSOURI DEPARTMENT OF CONSERVATION. (2023). Red Buckeye. MISSOURI DEPARTMENT OF CONSERVATION. Retrieved April 19, 2023, from <https://mdc.mo.gov/discover-nature/field-guide/red-Buckeye>
16Rhoades, C. C. (2006, October 1). The influence of American Chestnut (Castanea dentata) on nitrogen availability, organic matter and chemistry of silty and sandy loam soils. USDA. Retrieved April 19, 2023, from <https://www.fs.usda.gov/rm/boise/AWAE/scientists/profiles/Rhoades/The_influence_American_Chestnut.pdf>
17PlantVillage. (2023). Hazelnut (filbert). PlantVillage. Retrieved April 19, 2023, from <https://plantvillage.psu.edu/topics/hazelnut-filbert/infos>
18Yokoyama, K. M., Nakamoto, S. T., & Wabutoraoha, K. (1989, December). Cashew. College of Tropical Agriculture and Human Resources University of Hawaii. Retrieved April 19, 2023, from <https://gms.ctahr.hawaii.edu/gs/handler/getmedia.ashx?moid=3026&dt=2&g=12>
19Feeley, C. (2023). Black Walnut: The Killer Tree. IOWA STATE UNIVERSITY. Retrieved April 19, 2023, from <https://www.extension.iastate.edu/news/2005/jul/070701.htm>
20Beddes, T., & Drost, D. (2020, May). Peanuts in the Garden. UtahStateUniversity. Retrieved April 19, 2023, from <https://extension.usu.edu/yardandgarden/research/peanuts-in-the-garden>
21Herrera, E. (1997, January). Growing Pistachios in New Mexico. NMSTATE. Retrieved April 19, 2023, from <https://pubs.nmsu.edu/_circulars/CR532/index.html>
22Ohio Buckeye Photo by Dan Keck / CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. Resized and Changed Format. From Flickr <https://www.flickr.com/photos/140641142@N05/34135266891/sizes/c/>
23David D. Taylor. USDA. Retrieved from <https://www.fs.usda.gov/wildflowers/plant-of-the-week/aesculus_glabra.shtml>
24Aesculus glabra Photo by Daderot / CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. Resized and Changed Format. From Wikimedia Commons <https://commons.wikimedia.org/wiki/File:Aesculus_glabra_-_University_of_Kentucky_Arboretum_-_DSC09366.JPG>
25Ohio Buckeye Photo by Dan Keck / Public domain. Changed Format. From Flickr <https://flickr.com/photos/140641142@N05/36708599266>
26Species Information Image: Aesculus glabra – Stanley M. Rowe Arboretum – DSC03417 Photo by Daderot / CC0 1.0 DEED | CC0 1.0 Universal. Cropped, Resized, Changed Format. Wikimedia Commons. Retrieved February 8, 2024, from <https://commons.wikimedia.org/wiki/File:Aesculus_glabra_-_Stanley_M._Rowe_Arboretum_-_DSC03417.JPG>