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Rhus L.

Kingdom: Plantae Rank: Genus Parent: Anacardiaceae Status: Valid

Common Names:

  • SUMAC - English, United States of America

Morphological Description

Diagnosis: Shrubs or rarely small trees often forming thickets; leaves palmately 3-foliate or pinnately compound, often turning bright red in fall.


Notes: A genus of ca. 200 species of temperate and warm areas; Toxicodendron, recognized here as a separate genus, is sometimes lumped into Rhus as a section or subgenus. According to J. Hennen (pers. comm.), there are rust fungi that attack only Toxicodendron (Pileolaria brevipes Berk. & Ravenel) and others that attack only Rhus (Pileolaria patzcuarensis (Holw.) Arthur). Rhus species often display very early fall foliage color (often strikingly red); this is considered to serve as a “foliar fruit flag” which attracts birds that act as dispersal agents for the fall-ripening fruits (Stiles 1984). In contrast to Rhus species, which are all non-poisonous, Toxicodendron species are poisonous and can cause contact dermatitis. Some species are a source of tannin. (Ancient Greek and Latin name for SUMAC)