A genus of about 13 species, trees and shrubs, of temperate e. North America, w. North America, e. Asia, and se. Europe. Sectional classification shown in the key follows Du, Harris, & Xiang (2020).
ID notes:The following hybrids are known from our area and can be locally common: Aesculus ×neglecta Lindley [flava × sylvatica], Aesculus ×mutabilis (Spach) Scheele [pavia × sylvatica], and Aesculus ×bushii Schneider [glabra × pavia]. They can be recognized by their intermediate morphology.