Thymelaea passerina (L.) Coss. & Germ.
Family: Thymelaeaceae
Mezereon
Thymelaea passerina image
Morton Arboretum  
Annual herb with a taproot to 0.6 m tall Stem: upright or ascending, unbranched or long-branched, stiff, grooved to minutely wrinkled, hairless or nearly so. Leaves: alternate, stalkless, to 1.5 cm long and 2.5 mm wide, linear to linear-elliptic with a cartilaginous, jointed base and pointed tip, firm, hairless or nearly so. Flowers: usually one or two, in axils, stalkless, tiny, with four sepals forming a tube, no petals. Tube shortly four-lobed, hairy, and swollen below the lobes. Stamens eight, included. Fruit: a dry, indehiscent capsule, enclosed in the persistent sepals, to 2 mm long, egg-shaped. Seed black, hard, with a membranous wall (pericarp).

Similar species: No information at this time.

Flowering: mid-July to late September

Habitat and ecology: Introduced from Europe. Found along roads and railroads. Has also been found in waste ground and gravelly soil along a lake.

Occurence in the Chicago region: non-native

Etymology: Thymelaea comes from the Ancient Greek name for the mythological Daphne. Passerina is Latin for "like a sparrow."

Author: The Morton Arboretum

Taprooted annual to 6 dm, simple or with long, ascending branches; herbage glabrous or nearly so; lvs small, narrow, to 15 נ2.5 mm, with a jointed, cartilaginous base, fls 1-3 in the axils, 2-3 mm; hypanthium short-hairy, shortly 4-lobed, scarcely corolloid; fr ovoid, 2 mm, with thin pericarp appressed to the hard, black seed; 2n=40. Disturbed places; Eurasian sp., intr. in O., Ill., Wis., Io., Neb. and Kans. Apr.-Sept.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.