14. Euphorbia nutans Lag. (nodding spurge, eyebane)

Chamaesyce nutans (Lag.) Small

E. preslii Guss.

E. maculata L., misapplied

Map 1676, Pl. 377 h–j

Plants annual, with taproots. Stems 20–80 cm long, erect or more commonly ascending, often arched at the branch tips, several- to many-branched, not flattened toward the tip, tan to reddish brown, sparsely to moderately pubescent with woolly hairs, sometimes mainly toward the stem tip and around the nodes, the hairs sometimes in 2 bands along opposite sides of the stem. Leaves opposite, sessile or very short-petiolate. Stipules small scales 1.0–1.5 mm long, these not fused or, on 1 side of the stem, those from the adjacent leaf in each pair fused toward the base into a single small structure positioned between the leaf bases, variously irregularly toothed, fringed, or divided. Leaf blades 8–40 mm long, oblong to oblong-lanceolate, asymmetrical at the base, with the side toward the stem tip usually angled or rounded and the other side more or less truncate to cordate and expanded into a small, rounded auricle, mostly angled to a bluntly pointed tip, the margins finely several-toothed, both surfaces glabrous or more commonly sparsely to moderately pubescent with curved to more or less spreading, slender hairs mostly toward the base, the upper surface usually reddish-mottled or with a conspicuous reddish spot, the undersurface variously pale green or faintly to strongly reddish-tinged. Inflorescences axillary, of solitary cyathia or appearing as small clusters on short axillary branches. Involucre 0.5–1.0 mm long, glabrous on the outer surface (often hairy along the inner margin), the rim shallowly 4-lobed, the marginal glands 4, 0.3–0.5 mm long and more or less equal in size, the body oblong to nearly circular, green or occasionally reddish purple, with a relatively inconspicuous petaloid appendage 0.2–1.5 mm long, this white or pinkish-tinged. Staminate flowers 5–28 per cyathium. Ovaries glabrous, the styles 0.6–2.5 mm long, each divided 1/3–1/2 of the way from the tip into 2 slender lobes. Fruits 1.6–2.3 mm long, glabrous. Seeds 1.0–1.6 mm long, elliptic-ovate to ovate in outline, angular in cross-section, slightly convex at the base, the surface finely and irregularly wrinkled or with indistinct shallow, rounded cross-ridges, sometimes faintly so, dark brown, sometimes with a thin, white coating, this often more persistent along the angles than the faces, lacking a caruncle. 2n=12, 14, 22. May–October.

Scattered to common throughout the state (eastern U.S. west to North Dakota and New Mexico; Canada; introduced west to California, Europe). Banks of streams and rivers, exposed margins of ponds and lakes, edges of swamps, disturbed portions of upland prairies, and openings of mesic to dry upland forests; also pastures, fallow fields, margins of crop fields, railroads, roadsides, and open, disturbed areas.

Misapplication of the name E. maculata to the taxon here called E. nutans is discussed in the treatment of that species. Burch (1966) discussed the problems of assigning names to the four main entities in the nomenclatural complex and determined that the oldest valid name for the relatively robust temperate North American plants with ascending stems is E. nutans. Some earlier authors had used the name E. hypericifolia for this taxon, but Burch made a strong case for restricting that epithet to a different, mostly tropical species.