Family: Asclepidiaceae

Status:

Description:
A tall slightly woody herb 1-2m high. Leaves are narrow, opposite and dark green. Flowers are white, shortly tubular, about 1 cm across, and carried in drooping clusters in the leaf axils. Fruit is a papery green pod with a covering of long bristles. Seeds are large and black, with a parachute of fine white hairs. The plant exudes a milky sap when damaged.

Preferred habitat and impacts:
Grows in a wide range of open sunny habitats, usually forest margins or grassy remnant native vegetation of farming areas. Seldom becomes abundant on the south coast. Narrow-leaf cotton bush was originally introduced from South Africa as a garden plant, although it is seldom seen in gardens these days.

The plant is poisonous and has caused deaths in cattle, sheep and poultry. It is seldom consumed fresh, but may be dangerous if included in cut fodder or chaff. The main symptom of poisoning is gastro-enteritis. The bladder-like pods may be attractive to children as playthings.

This plant is the main food plant of the caterpillars of the wanderer butterfly (Danaus plexippus), a migratory American species which is now common in Australia, where it apparently arrived unassisted by human intervention.

Dispersal:
Wind-spread seed and suckering from the roots to a limited extent. Seed may also be spread in mud on vehicles and machinery or in contaminated grain or hay.

Look-alikes:
Flowers and fruits are distinctive, and the combination of narrow opposite leaves and milky sap is not shared by any native plants of the south coast.

Control:
Dig or hand pull small infestations, removing as many roots as possible to minimise suckering. Spot spraying will also be effective.