Family: Solanaceae (nightshades)

Status:

Description:
Straggly evergreen shrub or small tree to about 4m high. Large grey-green leaves, purple flowers followed by clusters of large (to 2cm) berries ripening from green to yellow. All parts of the plant are covered in velvety hairs. Crushed leaves have a strong smell of diesel fuel.

Preferred habitat and impacts:
A garden escapee. Widespread along rivers in Eurobodalla, but not yet well established further south. Tobacco bush is a coloniser of disturbed sites, and germination of soil stored seed is stimulated by fire.
Invades riverbank vegetation, and coastal scrub and forest, where it displaces and shades out native vegetation.
All parts of the plant are poisonous to humans, particularly the green berries. However, the ripe fruit may be a valuable food resource for native fruit-pigeons and other birds. If removing large infestations of wild tobacco bush, it would be preferable to replace them with fruit-bearing local natives. A fast growing but short-lived substitute is kangaroo apple (see below).

Dispersal:
Spread from seed in dumped garden waste, and by birds and other animals.

Look-alikes:
Quite distinctive in its size. There are smaller purple-flowered native nightshades (Solanum species), of which the most similar are Devil’s needles (Solanum stelligerum) and Solanum densevestitum. These also have furry grey-green leaves, but they are smaller and narrower, and the plants are usually only 1m high. Devil’s needles usually has some prickles scattered on the stems, as do most native nightshades found on the south coast, but S. densivestitum does not.

Two native shrubs or small trees, both typical of moist areas such as gullies and rainforest edges, can have large densely furry leaves, particularly on new growth. They are Clerodendrum tomentosum, whose leaves often have a purple leaf stalk, and Astrotricha latifolia, whose leaves are often held at an angle of nearly 90o to the leaf stalk. The upper leaf surface is green and glossy but the lower surface, leaf stalk and new growth is matted with clumps of soft woolly hairs.

Kangaroo apple (Solanum aviculare) and Solanum vescum are native nightshades with a similar growth habit to wild tobacco bush, and purple flowers. Their leaves are dark green, hairless, and narrow, or divided into 3 or more long narrow lobes. Fruits are orange, oval and about 1.5cm long. They are colonisers of disturbed moist sites.

The introduced shrub or small tree, tamarillo or tree tomato (Cyphomandra betacea), grown for its fruit, sometimes naturalises in moist shady sites. Birds spread its seeds. It has large oval to slightly heart-shaped green leaves, pithy stems similar to those of tobacco bush, and small pink flowers followed by large (to 7cm) egg shaped deep red fruits. The leaves of this plant also smell unpleasant when crushed.

Control:
Mature plants will re-sprout if cut down. Cut and paint or stem inject mature plants. Small plants may be hand-pulled.