Amaranthus pumilus is an annual C4 herb (Costea and Tardif 2003); monoecious, stems fleshy, branched, to 40 cm long, prostrate to reclining, reddish to pale green usually forming mats.
Leaves alternate, 1-2 cm long, in crowded rosettes toward tips of branches fleshy, pale blue-green, young leaves reddish, smooth, spoon-shaped, tip broadly rounded, often notched, base abruptly narrowed to short stalk, midrib and secondary veins deeply impressed the surface bulging and shiny between veins and sprinkled with tiny dots, margin entire.
Flowers greenish to yellow, 0.2-0.4 cm, in dense axillary clusters blooming and fruiting Aug.-Oct.
Fruit fleshy, 0.4-0.5 cm long.
Wetland status: FACW.
Frequency in NYC: Rare, (G2; Fed. status LT; NYS S1).
Habitat: Beaches above high tide line. Found well above high tide line in Piping Plover nesting area on Rockaway Beach.