Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Genus Description - Pet glabrous; fr a white or greenish-white to yellowish drupe, shining and glabrous or inconspicuously short-hairy, the hairs not glandular; allergenic shrubs or vines, with axillary, raceme-like, rather loose infls often drooping in fr; otherwise much like Rhus, and often included therein. Ca 10, New World and e. Asia.