1. Galium anglicum Huds.

G. parisiense L. var. leiocarpum Tausch

Map 2535

Plants annual, sometimes becoming slightly hardened at the base at maturity. Stems 10–30 cm long, usually weak, erect to loosely ascending or clambering, often branched and/or tufted, roughened with minute, prickly, downward-curved hairs on the angles. Leaves (2–)4–6(–8) per node, spreading or downward-angled in orientation. Leaf blades 1–6 mm long, 0.5–2.0 mm wide, narrowly elliptic to narrowly oblong or linear, angled or short-tapered to a sharply pointed tip, the midvein sometimes extended into a minute, sharp point, angled to truncate at the base, not glandular on the undersurface, with only the midvein visible, the margins with minute, stiff, prickly hairs and usually curled under. Inflorescences terminal and also axillary from the uppermost leaves, the axillary ones not pendant, positioned over the leaves, consisting of small clusters or fascicles, these usually grouped into small panicles with mostly 2 or 3(4) branch points and relatively short, ascending to less commonly spreading branches. Flowers relatively few, the stalks 0.5–2.0 mm long. Corollas 0.4–0.6 mm long, 4-lobed, white. Fruits about 1 mm long, 1.5 mm wide, the surface glabrous, smooth to granular. May–June.

Introduced, uncommon in the southern half of the state (native of Europe; introduced sporadically in eastern U.S. west to Missouri, Oklahoma, and Texas; also California, Oregon, Hawaii, Canada, New Zealand, and Australia). Glades; also ditches, cemeteries, lawns, and open, disturbed areas.

This species was first reported for Missouri by Lipscomb and Nesom (2007), who studied the introduced populations of the G. parisiense complex in the United States and determined that three species should be recognized. Galium anglicum was long-misdetermined as G. divaricatum or treated as a glabrous-fruited form or variety of G. parisiense. In the eastern half of the United tates, true G. parisiense appears to be established only in Alabama, Louisiana, and Mississippi, as well as sporadically in the southern 2/3 of Arkansas. Surprisingly, there are currently more specimens to document G. anglicum in Missouri than there are of G. divaricatum. The two may be separated by characters in the key to species above.