6. Lysimachia radicans Hook. (creeping loosestrife, trailing loosestrife)

Steironema radicans (Hook.) A. Gray

Pl. 510 i, j; Map 2326

Plants with relatively short, slender rhizomes. Stems 40–100 cm long, relatively slender to more commonly relatively stout (2–5 mm in diameter at the base), arched, trailing, or ascending from a spreading base (when young), often rooting at some of the nodes, glabrous except for a fringe of spreading hairs at each node. Basal leaves rarely present at flowering, shorter than the stem leaves, long- petiolate, the blade elliptic to lanceolate. Stem leaves opposite or in whorls of 3 at the upper nodes, with a mostly well-differentiated petiole, this 0.5–1.5 cm long, somewhat flattened, narrowly winged, the margins pubescent with long, spreading hairs below the midpoint, the pubescence sparse or absent toward the tip. Leaf blades 1–9 cm long, 0.3–3.0 cm wide, the uppemost blades sometimes linear, those of the main leaves lanceolate to oblong-elliptic or ovate, the bases mostly rounded to broadly angled (more narrowly angled on the uppermost blades), angled or somewhat tapered to a sharply pointed tip, the margins entire or more commonly roughened with minute papillae, the surfaces lacking gland dots, not punctate, glabrous, the upper surface green to dark green, the undersurface lighter green; secondary veins evident. Inflorescences axillary from the uppermost nodes, of solitary flowers, the flower stalks 0.7–3.0 cm long, glabrous. Calyces (4)5-lobed, the lobes 3–4 mm long, lanceolate, not gland-dotted or punctate, usually with 3–5 relatively faint veins. Corollas (4)5-lobed, the lobes 3–5 mm long, obovate to broadly obovate, broadly rounded to nearly truncate at the tip, sometimes with a minute, extended point at the tip, the margins otherwise slightly uneven or toothed toward the tip, yellow, densely glandular and with reddish markings on the upper surface toward the base, lacking purple spots or lines. Stamens shorter than the corollas, the filaments 1.5–2.5 mm long, not fused into a basal tube, glandular-hairy. Staminodes alternating with the stamens, slender above a somewhat broadened base. Styles 3–4 mm long. Fruits 3–4 mm long, broadly ovoid to globose. Seeds 1.1–1.4 mm long, irregularly elliptic, oblong, or rhombic in outline, triangular in cross-section, dark brown to reddish brown, shiny. 2n=34. June–September.

Scattered in the Mississippi Lowlands Division and uncommon in the southernmost portion of the Ozarks (southeastern U.S. west to Oklahoma and Texas). Swamps, bottomland forests, and margins of sinkhole ponds; also ditches and wet roadsides.

The two historical specimens originally thought to represent disjunct occurrences in Jackson County and the city of St. Louis lack detailed locality data. John Kellogg’s 1910 collection from St. Louis may represent an introduced population or a cultivated plant. Steyermark (1963) noted that although Henry Eggert’s 1892 collection from Blue Springs was attributed to Jackson County in J. D. Ray’s (1956) monograph of the genus, Eggert never botanized in the Kansas City area and it is more likely to have originated from one of the Blue Springs that are in several counties in the southeastern portion of the state. Examination of specimen data entered into the Flora of Missouri Database discloses that Eggert collected only in Butler County on 19 August 1892, and a specimen of Helenium amarum collected that day from “near Blue Spring” is clearly labeled as having originated from Butler County.