Coffeetrees have large tough seedpods, which remain on the tree until early spring.  The seedpods contain sweet pulp and large seeds, with a thick waterproof coating that needs to be cut or abraded before germination.  This seed protection probably evolved with, and to be spread by, mammoth.  After the Holocene extinction removed large herbivorous megafauna, poor seed-dispersal caused the plant's range to decline to floodplains in the 🇺🇸 USA Midwest and Upper South.  Although the raw seeds are toxic to humans, after roasting they are not;  early European settlers in Kentucky used these roasted beans as a coffee substitute, resulting in the tree's common name.[1]

It is now planted occasionally as a shade-tree.

References
[1] The Trees That Miss The Mammoths by Whit Bronaugh retrieved 2016-12-06 by EP.

Uses by native peoples
(Ethnobotany database)

Learn more about Kentucky coffeetree Gymnocladus dioicus

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