Kentucky Coffee-tree (Gymnocladus dioicus)

Life history

Species overview

Kentucky Coffee-tree (Gymnocladus dioicus), a Wisconsin Special Concern plant, is found in rich alluvial or mesic forests. Blooming occurs throughout June; fruiting occurs early July through early September. This species can be identified year-round.

Synonyms: Guilandina dioica

Identification

• Distinguishing characteristics: Leaves very large, bipinnately compound with leaflets mostly 1.5 to 4 cm wide; fruit an oblong, flattened pod with large, hard seeds in a sticky pulp; twigs stout and unarmed.
• Flower characteristics: Spike-like flower heads 6 to 20 cm long, open, growing from the end of the branches; flowers numerous, greenish-white, star-shaped, and covered with tiny soft hairs; petals 8 to 10 mm long, oblong or inversely lance-shaped.
• Fruit characteristics: Seed pods oblong, flattened, 8 to 25 cm long and 3 to 5 cm wide; seeds 10 to 15 mm long, bean-shaped, thick and hard, in a sticky pulp when fresh.
• Leaf characteristics: Bipinnately compound leaves grow to nearly 1 m in length (look back to woody twig and bud at base of stout petiole to determine length of leaf), with many pairs of sharply pointed, egg-shaped 3 to 8 cm x 1.5 to 4 cm leaflets.

Phenology

• Blooming phenology: throughout June
• Fruiting phenology: early July through early September
• Optimum time to identify: This species can be identified year-round

Other

• Growth form: Tree
• Vegetative reproduction:
• Life cycle: Perennial
• Comments: Associated Species: Fraxinus pennsylvanica, F. americana, Tilia americana, Acer saccharum, Juglans nigra, Celtis occidentalis, Carya cordiformis, Betula nigra.

State status

Status and Natural Heritage Inventory documented occurrences in Wisconsin

The table below provides information about the protected status - state and federal - and the rank (S and G Ranks) for Kentucky Coffee-tree (Gymnocladus dioicus). See the Working List Key for more information about abbreviations. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Habitats and landscapes

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

General habitat information

• Habitat description: Found in rich alluvial or mesic forests.
• Soils: Rich, moist soils.

Natural communities

This table lists the natural communities that are associated with Kentucky Coffee-tree. Scores for natural community associations are: "significant" association (score=3), "moderate association" (score=2) or the species can be present but is only weakly associated with the community (score=1).

Ecological landscapes

This table lists the ecological landscape association scores for Kentucky Coffee-tree. The scores (3=High, 2=Moderate, 1=Low, 0=None) also correspond to the map.

Species guidance

The Endangered Resources Program has developed avoidance measures and management guidelines for plants on the Natural Heritage Working List. These are a work in progress, and we welcome your suggestions and feedback. Sources used in developing this information can be found here.

Avoidance measures

These are specific actions designed to avoid "take" (mortality) of this species.

• Avoid locating landings, staging areas, or access routes on or near known populations.
• Avoid broadcast spraying of herbicides; use care with spot spraying.
• Avoid known individual plant locations and conduct operations elsewhere when they are least likely to cause damage. Ideally, this would involve frozen, snow-covered ground. However, in areas of the state where frozen conditions are unreliable, very dry soils late in the growing season might be the best available alternative. Consult with a biologist, if needed.

Management guidance

Management guidelines are additional considerations that may help maintain or enhance habitat for this species

• Minimize disturbance to hydrology, including soil disturbance from rutting.
• Although maintaining high overall forest canopy is important, silvicultural techniques which open small gaps in the canopy may be beneficial to this species.

Other resources

Links to additional Kentucky Coffee-tree information

Other links related to vascular plants (all exit the DNR website)

• Wisconsin Flora
• NatureServe Explorer
• Atlas of Wisconsin Prairie and Savanna Flora - Wisconsin State Herbarium
• USDA - NRCS Plants Database
• USGS Midwestern Wetland Flora - field office guide to plant species
• eFloras
• Cofrin Center for Biodiversity Herbarium
• Intermountain Herbarium Grasses of North America
• Orchids of Wisconsin

Photos

Click to view a larger version. Please considering donating a photo to the Natural Heritage Conservation Program for educational uses. Photo use