Pilea pumila (L.) A.Gray
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Annual, very smooth and pellucid, 1–5 dm; lvs long-petioled, shining, ovate, 3–12 cm, serrate or crenate-serrate, broadly cuneate to rounded at base, usually glabrous, 3-nerved from the base, the nerves narrowly winged; terminal lf-tooth elongate; cymes 5–30 mm from the middle and upper axils; cal-lobes equal or nearly so; achenes pale green, usually with slightly raised purple spots, 1.3–2 mm, 55–70% as wide as long; seed smooth. Moist, rich, shaded soil, often in colonies; Que. to Minn., s. to Fla., La., and Okla. July–Sept. (Adicea p.) Northeastern plants have the lvs sharply cuneate at base, with 11 or fewer rounded teeth on each side. Toward the s. and w. the lf-base tends to be more rounded, and the teeth sharper and more numerous; this poorly defined phase has been called var. deamii (Lunell) Fernald.