Flora of North America species comparison

prostrate or decumbent, 1–30 cm, freely rooting at nodes, forming mats.

decumbent, freely branching or simple, 1–10 cm, often rooting at nodes, forming small, loose mats.

opposite, sessile;

blade oblanceolate to rhombic, 2–20 × 0.5–10 mm.

alternate, not distinctly petiolate, with clasping leaf sheaths;

blade linear, 5–25 × 1–2 mm.

leafy.

axillary, 1-bracteate;

bract minute, scarious.

1–8, slightly bilateral;

sepals 1–1.5 mm;

petals 5, connate proximally, white, unequal, 1–2 mm;

stamens 3, anther pink or yellow.

2–8;

sepals 1–2 mm;

petals 2–5, often absent, white, 0.7–1.5 mm;

stamens (2–)3(–5), anther pink.

0.7–1.2 mm, tuberculate;

elaiosome present.

0.5–1 mm, tuberculate;

elaiosome minute, shorter than 0.5 mm.

= 20, 40.