Flora of the Hawaiian Islands
Dicotyledon Literature for Euphorbia hirta
Wagner et al., 1990, 1999; Lorence & Wagner, 2020.
   Euphorbiaceae -- The Spurge Family Bibliography
      Euphorbia hirta

Common name(s): spurge, garden spurge, hairy spurge, koko kahiki
General Information
DistributionNative from southern United States to Argentina, the West Indies, and the Paleotropics.In the Hawaiian Islands, naturalized on Kure, Midway, French Frigate Shoals, Ni`ihau, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Kaho`olawe, Hawai`i.

Annual herb; stems 2–60 cm, decumbent, tomentose with short, curly hairs interspersed with longer, spreading, yellow hairs.
Leaves distichous, slightly unequal; blade green, sometimes tinged red, often with red spots, membranous, ovate to rhombic-ovate or lanceolate, 5–50 mm long, 3–18 mm wide, appressed pilose, margin serrate, apex acute, base acute, rounded, or subcordate; petiole 1–2 mm long; stipules linear lanceolate, 1–2 mm long, ciliate.
Cyathia in congested, lateral, short pedunculate, few flowered cymes; involucre 0.5–0.8 mm high, densely strigose to glabrate, glands 5, orbicular, 0.1–0.3 mm long, appendages white, glabrous, margin entire, often absent. Staminate flowers 2–8 per cyathium.
Fruit broadly ovoid, 3-angled, 0.8–1 mm long, 1–1.2 mm in diameter, strigose.
Seeds pale brown, ovoid, falcate, 4-angled, 0.5–0.7 mm long, faces wrinkled.
2n = 12, 16, 18, 20.
Nancy Khan