pronounced: trick-oh-DEZ-muh zey-LAN-ih-kum
Trichodesma begins with the Greek word τριχος (trichos), hairy. This is a very hairy plant! The –desma probably comes from the Burmese term for poison – some claim that plants of the genus are poisonous to stock. Zeylanicum is botanical Latin for ‘from Ceylon’ (now Sri Lanka). The native range of the plant is from eastern tropical Africa to India, Sri Lanka, the Malay Peninsula, New Guinea and northern Australia. It has become naturalized in many of the Pacific Islands, particularly Fiji.
This is an erect annual or perennial herb to about 1 m or a little more in height, with a well-developed taproot. Much of the plant is covered with irritating bristles and small hairs, including the stems and the leaves. At the base of the plant the leaves are opposite, but they become alternate as one moves up the stem. They are shortly petiolate, and elliptic. The apex is usually acute, but sometimes obtuse.
The inflorescence is raceme-like, the individual flowers (1.5 – 2 cm in diameter) blue, rarely white. The sepals are narrow-ovate, 1 – 1.5 cm long, 3 – 4 mm wide, broadening in fruit. The flowers usually become nodding soon after sun-up. The fruits have four spherical-shaped chambers, each with one seed.
There are quite a few of these plants on the path leading down from the road near the Rocky Bay lookout to the back of Picnic Bay, mostly on the lower end of the path, as they like to be near sea level. Although usually regarded as a weed, the flowers of this plant are pretty.
The leaves are used in folk medicine, usually as a soothing poultice. They have sudorific properties (i.e., they promote sweating), and are used for treating chest ailments. In some places, particularly in Fiji, the leaves are used for the treatment of leucoderma (localized loss of skin pigment), and for piles. The roots are also powdered and the powder used to treat painful ulcers.
Many claim that the plant is poisonous to stock; but the only evidence I have come across is anecdotal.