Also called American chinquapin, Ozark chinquapin, dwarf chestnut, and Castanea ozarkensis. Also spelled chinkapin.
The word chinquapin comes from the nut chechinquamin, in Eastern Algonquian, specifically Virginia Algonquian or Powhatan.
Despite their similar common names, do not confuse with another species from a sister-genus
chinquapin oak Quercus muehlenbergii.
Although they are in the same family.
Part of
🌰︎ chestnut / chinkapin genus Castanea
in
beech / oak family Fagaceae
in
bayberry / beech / birch / oak / walnut order Fagales.
Native to 🇺🇸 USA South, 🗻︎ Allegheny Mountains, and mid-Atlantic.
🗺 Map (North America, Central America). 
Formerly abundant, this tree is having a tough time with a bark fungal disease
chestnut blight Cryphonectria parasitica.
Although not having as hard a time as this tree's closely-related (with whom it shared most of their home ranges) sister-species
🌰︎ American chestnut Castanea dentata.
Uses by native peoples
(Ethnobotany database)
Castanea hosts caterpillars of 129 species
of butterflies and moths, in some areas.