A genus of 9-11 species, shrubs, of North America and Cuba, except the circumboreal K. procumbens (formerly Loiseleuria). Leiophyllum, traditionally treated as a monotypic or small genus of se. United States, is better treated as a part of Kalmia along with the northern Loiseleuria, based on molecular and morphological studies (Kron & King 1996, Kron et al. 2002). While this idea may initially seem outlandish (particularly to those whose concept of Kalmia is based only on Kalmia latifolia), the morphological and habital similarities of Leiophyllum to Kalmia are striking. The foliage and wood of all species (and the smoke from burning them) are poisonous.
Ref: Camp (1938); Ebinger (1974); Haines (2010); Kron & King (1996); Kron et al. (2002); Kron, Judd, & Anderberg (2008); Liu et al. (2009) In Flora of North America Editorial Committee (2009); Southall & Hardin (1974); Stevens et al. In Kubitzki et al. (2004); Strand & Wyatt (1991); Wilbur & Racine (1971). Show full citations.