Chenopodium ambrosioides
Content
Description
Annual or perennial, taprooted herb. Stem 0.3-1.0(-1.5) m tall, strongly scented of mustard, ribbed, often somewhat woody, much-branched. Petiole 1-2 cm long; blade lanceolate, oblanceolate, oblong-elliptic, rhombic-elliptic or ovate, 0.6-12.5 x 1-5.5 cm, entire to shallowly dentate or sinuately pinnatifid, apex acute to obtuse, sometimes apiculate, base cuneate, sessile glandular resin dots, especially on lower surface, glabrous or sparsely puberulent above, or puberulent beneath especially on veins, yellowish-green. Inflorescence a single cyme or spikes of cymes; flowers in glomerules of 4-6, along major axes, in groups of 1-3 on apical, minor axes; glomerules 1-bracteate, bract linear to (sub)foliaceous, to ca. 2.5 cm long; flowers sessile or subsessile. Tepals (3-)5, greenish, narrowly ovate, 0.7-1.3 mm long, glabrous or puberulent and usually gland-dotted, fused ca. half-way, cucullate and folded over fruit; stamens (3-)5; filaments about as long as tepals, anthers orbicular, 0.5 mm long; stigmas sessile or subsessile, spreading. Pericarp not adherent to seed, thin and decaying; seeds lenticular-cochleate to ovoid, 0.6-0.8 mm in diam., horizontally or vertically oriented, smooth, lustrous, reddish-brown.
Distribution
Guianas present, Northern America, Southern America
Possibly native to Mexico and Central America, now a cosmopolitan weed in warm regions; 21 collections examined, all from the Guianas (GU: 6; SU: 1; FG: 14).
Common Name
Boni (French Guiana): woron-wiwiri; Creole (French Guiana): poudre aux vers, zerb' a vers; Creole (Suriname): woron-menti; English (French Guiana): aapoa, semen contra; English (Guyana): mastruz, matouosh, metroshi; English (Suriname): tingi-menti
Uses
Generally found as a weed, sometimes cultivated as a medicinal plant for the leaves, which are used as an anthelmintic (vermifuge) in the Guianas (Cook 250; Ostendorf (1962); and Moretti 913). The French Guianans use an infusion of six leaves mixed with salt in a cup, which is reportedly very beneficial for the liver, and as a children's vermifuge (Oldeman B.3909). According to Henkel 3467, the plant is used as a malaria treatment by Wapishiana Amerindians of Guyana.