Euphorbia hirta L.
asthma plant
Annual, usually erect or spreading. Stems moderately to densely hairy, 10-30 cm long, branched or not from base. Lvs opposite, sparsely to moderately hairy above, usually densely hairy below, shortly petiolate, serrate, ovate to elliptic, acute, asymmetric at base, (6)-10-20-(30) mm long, often with a purple spot about midvein; stipules triangular, free, c. 1 mm long, often with long linear divisions. Cyathia in small, axillary or terminal, leafless clusters along branches. Glands ovate or orbicular, entire. Capsule smooth, grooved, sparsely to moderately clothed in appressed hairs; keels sharp. Seeds rugulose, 4-angled, reddish brown, 0.7-1 mm long.
N.: collected once from Silverdale, N. Auckland; K.: confined to thermal sites on Raoul Id.
Tropical America 1910
Open disturbed sites, arable land.
Asthma plant is a widespread and troublesome weed of cropland in many tropical and subtropical regions. It has been known from K. since early this century but is apparently not spreading, and has been only recently recorded for mainland N.Z. It was first recorded as E. pilulifera.
