16. Acalypha virginica Linnaeus, Sp. Pl. 2: 1003. 1753. name conserved.
[E F W]
Virginia threeseeded mercury Virginia threeseeded mercury
Acalypha digyneia Rafinesque
Herbs, annual, 1–5 dm, monoecious. Stems usually erect, sometimes ascending, pubescent and usually hirsute. Leaves: petiole 0.3–7 cm; blade narrowly rhombic to broadly lanceolate, 1–8(–11) × 0.5–3(–4) cm, base acute, margins serrate, apex acute to acuminate. Inflorescences bisexual, axillary; peduncle 0.1–0.6 cm, pistillate portion 0.7–1.5 × 1.3–1.7 cm or pistillate bract solitary, staminate portion 0.3–1(–1.8) cm; allomorphic pistillate flowers absent. Pistillate bracts loosely arranged to crowded (inflorescence axis clearly to scarcely visible between bracts) or solitary, 6–13 × 9–20 mm, abaxial surface hirsute and sometimes stipitate-glandular; lobes (9–)10–14(–16), triangular, 1/4–1/2 bract length. Pistillate flowers: pistil 3-carpellate; styles multifid or laciniate. Capsules smooth, pubescent. Seeds (1.2–)1.5–1.6(–1.8) mm, minutely pitted.
Flowering and fruiting summer–fall. Deciduous and evergreen woods, riverbanks, agricultural fields, disturbed areas; 30–1200 m; Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Tex., Va., W.Va.
Acalypha virginica overlaps geographically with A. rhomboidea but is more frequently found in grassy or prairielike habitats. See the discussion of 15. A. rhomboidea for notes on the nomenclatural and taxonomic confusion associated with these species.
Acalypha virginica and A. gracilens can sometimes be difficult to distinguish, especially when young. They can generally be distinguished by the pistillate bracts, which in A. virginica are hirsute and lack red sessile glands abaxially and in A. gracilens are sparsely pubescent and bear some red sessile glands abaxially.
Reports of Acalypha virginica from states other than those listed here are based on misidentifications.