Species At Risk

Kentucky Coffee-tree

(Gymnocladus dioicus)


Kentucky Coffee-tree
Kentucky Coffee-tree occurrences map


The Kentucky Coffee-tree grows 15 to 25 metres high. The leaves are as big as 60 by 90 centimetres, the largest leaves of any Canadian tree. They are twice compound, divided into many, small bluish-green leaflets. The flowers are greenish-white in colour. The fruit is a hard, dark, leathery and bean-like pod, about 15 to 25 centimetres long. The fruit contains four to seven seeds and remains on the tree throughout the winter. Kentucky Coffee-tree may grow singly or in larger groups where multiple trunks emerge from the same root system.

Action we are taking:


The Kentucky Coffee-tree is rare throughout its range, which extends from the southern Great Lakes region east to New York in scattered localities, south to Oklahoma and Arkansas, and west to Kansas and Nebraska. In Canada, it is only found in southwest Ontario where it was documented at 20 locations in 2000.


Kentucky Coffee-tree is found in a variety of habitats, but grows best on moist rich soil. Consequently, it is often found in floodplains, though it will tolerate shallow rocky or sandy soils. It is shade-intolerant, and therefore grows along the edges of woodlot or relies on canopy openings in forests and woodlots.


The greatest threats to the Kentucky Coffee-tree are lack of suitable or good quality habitat and poor seed production. Male and female flowers occur on separate trees, and unless both sexes occur in close proximity, trees will not produce seeds. Many populations in Ontario are unisexual and therefore must rely on vegetative reproduction (without a seed). Where seeds are produced, effective dispersal mechanisms are often lacking due to flood control. Clearing of land for agriculture also seriously threatens this species. Large populations of Double-crested Cormorants threaten some populations of Kentucky Coffee-tree in the Great Lakes region because their droppings accumulate at nesting colonies in quantities that are toxic to this rare tree. The planting of ornamental Kentucky Coffee-trees from non-native stock may pose a threat since their genes may contaminate the locally adapted gene pool.


The Kentucky Coffee-tree receives protection under Ontario’s Endangered Species Act and the federal Species at Risk Act.

What You Can Do to Help the Kentucky Coffee-tree

  • The Ministry of Natural Resources tracks species at risk such as the Kentucky Coffee-tree. You can use a handy online form to report your sightings to the Natural Heritage Information Centre. Photographs with specific locations or mapping coordinates are always helpful. nhic.mnr.gov.on.ca
  • Report any illegal activity related to plants and wildlife to 1-877-TIPS-MNR (847-7667).
  • Private land owners have a very important role to play in species recovery. If you find a Kentucky Coffee-tree on your property, you may be eligible for stewardship programs that support the protection and recovery of species at risk and their habitats.
  • Consult the Ministry of Natural Resources for information on provincial regulations and best management practices when working around forests. Call toll free 1-800-667-1940 or visit the Ministry website at www.mnr.gov.on.ca/en/ContactUs/2ColumnSubPage/STEL02_179002.html.
  • Volunteer with your local nature club or provincial park to participate in surveys or stewardship work focused on species at risk.
  • Pollinators, such as bees, are in steep decline across the globe and they play a key role in the survival of many of Ontario’s rare plants. For information on how you can help scientists monitor pollinator populations in Ontario visit: www.seeds.ca/proj/poll.
  • The Carolinian forests of southern Ontario support an amazing diversity of plants and wildlife, including many species at risk. Carolinian Canada is working to help recover species at risk and their habitats. For more information, visit: www.carolinian.org/SpeciesHabitats.htm.

Did you know?

The leaves and seeds of Kentucky Coffee-tree contain a toxic substance, the alkaloid, cytosine, which may be fatal if consumed. However, aboriginal people used the roasted seeds of the Kentucky Coffee-tree to treat headaches and relieve digestion problems. Roasting is supposed to neutralize the toxins.

Did you know?

Part of the Latin name for the Kentucky Coffee-tree (Gymnocladus dioica) means "naked branch", because this tree spends up to nine months of the year without any leaves.

Did you know?

The only other species in the genus of Kentucky Coffee-tree is a tree that grows only in China.

Did you know?

Because no native herbivores consume the toxic Kentucky Coffee-tree seeds – and since elephants devour similar seed pods in great quantities – it has been hypothesized that the now-extinct Mastodon may have consumed Kentucky Coffee-tree pods. In fact, Kentucky Coffee-tree may have evolved its unique seeds, which seem unpalatable to native animals, specifically for Mastodon-assisted dispersal.

The Endangered Species Act

Contact your local ministry office

Often the best source of local information on species at risk is your nearest ministry office. Call with your questions or concerns.