Ardisia elliptica Thunb.
(Primulaceae – the primula family. Sometimes placed in Myrsinaceae, the colicwood family)
common name: Shoe-button Ardisia
This is a shade-tolerant evergreen tree whose fast growth and attractive fruit made it a popular ornamental plant in the past. It has escaped from private and public gardens to invade natural areas. Due to high reproductive output and high shade-tolerance, carpets of seedlings can form underneath adult trees. High seed viability (99%) and seed consumption by both avian and mammalian frugivores can lead to rapid spread across a landscape. In a number of countries it has formed dense monotypic stands that prevent establishment of all other species: this has occurred in Hawaii, southern Florida, Okinawa and Jamaica. It is listed as an ‘alert weed’ to be reported to Weeds Australia whenever discovered. The plant has the potential to spread right along the whole east coast of Queensland, across the top of Cape York, Arnhem Land, and the Kimberleys. It has already become naturalized in several areas of the Northern Territory in riparian vegetation within areas of dry rainforest associated with the monsoon belt.
Ardisia is from the Greek αρδις (ardis) the point of an arrow, referring to the pointed anthers; elliptica is from ελλειψις (elleipsis), a falling short, and refers to the elliptic shape of the leaves.
The tree is native to the west coast of India, Sri Lanka, Indochina, Malaysia, Indonesia and New Guinea. It is a tropical understorey shrub that can grow to about 4 m; undamaged plants in forest habitats are characterized by a single stem, producing short perpendicular branches. Its branchlets are hairless; the leathery leaves are dull, gland-dotted below, with entire margins, 6–12 cm long, 1.5–5 cm wide, with margins rolled under, on stalks 5–10 mm long. New foliage is red-tinted.
The flowers occur in umbels in the leaf axils; the corolla is pink or white with 5 lobes, and gland-dotted. The fruit is a drupe, fleshy and single-seeded, about 8 mm wide, turning red as it matures, and dark purple to black at maturity. The calyx persists at the base. If the fruit is handled, the pulp will stain the fingers a deep purple. The seed is approximately spherical, about 5 mm in diameter.
In Malaysia, a decoction of leaves is used to treat retrosternal pains, and a paste made from the leaves is used to treat herpes and measles. In Thai traditional medicine, the fruits are used to cure diarrhoea with fever; and in south-east Asia the leaves are used to treat scabies, and the fruit for intestinal worms.
Photographs © Donald Simpson, taken in Picnic Bay, 2011