Invasive Alien Species

Species Name: Waltheria Americana

Family Name:
Sterculiaceae
Synonym:
Waltheria indica L.
Origin:
Probably Tropical America
Description:
An erect sub-shrub, often woody at the base, 30-150 cm tall. Petiole 2 cm long, leaves broadly ovate-oblong, the base rounded, or sub-cordate,  1.5-7 x 1-6 cm , the terminal one much reduced, grayish tomentose beneath, finely dentate. Inforescence glomerated in leaf axils, sessile or shortly stalked, 5 mm long; bracts and sepals pale green, corolla somewhat exserted .Fruit capsules small, membranous, enclosed by persistent calyx, hairy toward the top. Seeds trigonous, smooth, reddish brown, 2 mm long.
Invaded Habitat:
Dry, sunny grassy fields, arable lands, dams, dunes, rubber plantations in West Java, oil palm plantations in Bangka island.
Distribution:
Java, Sumatra.
Ecology:
Flowers throughout the year, in Java found at 5-125 m alt.
References:
  1. Backer, C.A. and R.C. Backhuizen van den Brink. 1963. Flora of Java.  Vol. I., N.V. Noordhoff-Groningen, The  Netherlands
  2. Pancho, J.V. and S.R. Obien. 1983. Manual of Weeds of Tobacco Farms in the Philippines. Philippine Tobacco Research and Training Center, Mariano Marcos State University, Batac, Ilocos Norte, The Philippines.