1. Salicornia europaea L. (glasswort, samphire)

Map 1549

Plants annual, the taproot not tuberous-thickened. Stems 10–50 cm long, erect with ascending to spreading branches, succulent, appearing cylindrical and jointed, usually much-branched, glabrous. Leaves opposite, fused into a small sheath, the free portion reduced to tiny scales, these 1.0–1.5 mm long, broadly triangular, rounded to bluntly pointed at the tip, glabrous. Inflorescences terminal, dense spikes with tiny clusters of 3 flowers in pairs at the nodes, these sunken into the axis. Flowers perfect, the central flower of each cluster positioned slightly above the lateral pair. Bracts reduced to tiny, broadly triangular scales, these fused basally into a low cup, bluntly pointed at the tip. Calyx 0.5–0.7 mm long, obpyramidal, splitting across the tip at maturity into 3 more or less truncate lobes, persistent at fruiting, mostly enclosing the fruit, not winged. Stamens 2. Ovary superior. Styles 2, short, fused toward base, the stigmas 1 per style, linear. Fruits 1.0–1.5 mm long, broadly elliptic in cross-section, ovate in outline, slightly flattened laterally, indehiscent or irregularly dehiscent, the wall thin and papery to membranous. Seed adhering loosely to the fruit wall, positioned vertically, 1.0–1.5 mm long, ovate to oblong in outline, somewhat flattened, the surface with scattered minute, curved hairs, greenish brown to brown, not shiny, the coiled embryo usually not apparent. 2n=36. July–September.

Introduced, known from a single historical collection from St. Louis County (coastal areas of North America, Europe, Asia, Africa; introduced sporadically farther inland). Open, disturbed areas, in sandy soil.

This distinctive species frequently grows in coastal salt marshes and other places with saline soils. In the Midwest it is an uncommon introduced species known from few populations, most of which probably did not persist for very long. The specimen collected in Valley Park in 1927 was overlooked by Steyermark (1963).

Salicornia europaea is treated here in the broad sense to comprise a circumboreal polyploid complex. The North American plants belong to a tetraploid (2n=36) variant that has sometimes been treated as a separate species, S. virginica L., with the name S. europaea then restricted to a diploid (2n=18) taxon restricted to Europe. Further studies are needed to resolve the subtle patterns of morphological variation in the group and to assess the relationships of the polyploid taxa to the diploids (Clemants, 1992; Judd and Ferguson, 1999).