3. Stellaria media (L.) Vill. (common chickweed)

Map 1498, Pl. 349 d, e

Plants annuals or short-lived perennials, green to dark green or rarely yellowish green. Stems 10–80 cm long, erect or ascending to spreading, branched, usually short-hairy in longitudinal lines, rarely nearly glabrous. Leaves petiolate (basal and lower stem leaves) or sessile (median and upper stem leaves). Leaf blades 0.3–4.0 cm long, ovate to elliptic, rounded to nearly truncate at the base, angled or slightly tapered at the tip, the margins glabrous or inconspicuously hairy. Flowers not cleistogamous, in terminal clusters or sometimes solitary, the stalks 0.3–4.0 cm long, ascending at flowering, often angled downward from the base at fruiting, the bracts herbaceous and resembling small leaves. Sepals 5, (3.0–)4.0–4.5(–6.0) mm long, oblong-lanceolate, lacking a reddish band at the base, bluntly pointed at the tip, the margins thin and white, finely hairy. Petals 5 or occasionally absent, when present 1–4 mm long, shorter than to about as long as the sepals. Stamens 3–5(–8). Fruits 4–6 mm long, the valves ascending or rarely recurved at dehiscence. Seeds (0.8–)0.9–1.4 mm wide, the surface tuberculate, the tubercles along the marginal portion broader than tall, more or less hemispherical, blunt or rounded at the tip, brown to reddish brown. 2n=40, 42, 44. January–December.

Introduced, scattered to common throughout the state, more abundantly south of the Missouri River (native of Europe; introduced throughout the U.S. [including Alaska, Hawaii]; Canada, also nearly worldwide). Banks of streams, rivers, and spring branches, bases and ledges of bluffs, sloughs, and bottomland forests; also pastures, crop fields, fallow fields, ditches, lawns, gardens, roadsides, and disturbed areas.

Stellaria media is one of the most widely distributed weeds in the world. This species is morphologically quite varied and specimens collected in the spring can be difficult to distinguish from the closely related S. neglecta and S. pallida. Small plants flowering early in the growing season can be confused easily with S. pallida, and robust plants can be very similar to S. neglecta. In both cases, seed size and ornamentation are important diagnostic features.

Steyermark (1963) noted that in its native range, young herbage of this species sometimes was gathered for use as a spinach substitute. He also discussed that birds (including domesticated songbirds) relish the seeds and that livestock sometimes eat the plants. He advised caution, however, citing anecdotal reports of poisoning of lambs that had ingested large quantities of this species.