Plant: tree; rapidly growing tree to 20 m tall, sometimes producing clonal thickets via rhizomes; young parts more or less glandular-puberulent; bark smooth; wood soft, brittle, with a broad pith Leaves: (1-)3-10 dm long; leaflets 9-31, (5-)8-15 cm long, lanceolate, with (1-)2-4(-6) large glands on the margin below, these situated near the base, terminating a small tooth or lobe Inflorescence: a large terminal panicle, 1-4 dm long Flowers: small, greenish to whitish; calyx less than 1 mm long; petals 2-3 mm long, woolly on and near the proximal margins; filaments pubescent basally; disk lobed; ovary with 2-5 flat 1-carpellate divisions Fruit: samaras, 3-5 cm long, linear, curved or oblique at the base, twisted 1/2 turn at the apex; seed-bearing portion near the center, 3-7 mm wide Misc: near buildings, roads, streams, and washes; at least 350-1700 m (1100-5500 ft); Apr-Jun REFERENCES: Brasher, Jeffrey W. 1999. Simaroubaceae. Ariz. – Nev. Acad. Sci. 32(1).