The African tulip tree is an evergreen species indigenous to western Africa. It has been introduced throughout the tropics and is threatening biodiversity in many parts of the Pacific islands. It favours moist habitats and will grow best in sheltered tropical areas. The tree invades both abandoned agricultural land and closed forest. This species loves rich soil, but puts up with just about any type of soil.

A coniferous tree growing up to 15m high, conical in shape with a short trunk when young and rounded to oblong with a crooked trunk when older. Crown open with silvery-grey bark becoming darker. Grey-green to yellow-green leaf needles in bundles of two 4-8cm long. It invades grasslands and fynbos, particularly on dry soils

Apple of Peru is an annual shrub growing to 1m tall. It has spreading branches (the plant spreads to 1m wide) and the mid-green, toothed, wavy leaves are egg-shaped with the broad end at the base (ovate). The upward-facing flowers are most commonly pale blue and white, but there are also forms with violet or white flowers. The flowers are bell-shaped and 5cm or more across. Cherry-like, green-brown berries are encased within green or black mottled calyces. The mature fruits can resemble a lantern. The plant usually germinates in late spring or early summer. 

The arsenic bush is a poisonous shrub that can grow up to 2-3m tall with yellow flowers. The leaves are arranged in pairs opposite each other, consisting of three or four pairs of ovate leaflets. The pods are cylindrical, 7-10cm long, containing shiny seeds. It is a common garden ornamental plant that also invades forest margins, savannah, riverbanks, roadsides, waste ground and plantations. It flowers from October to March.

A large, densely branched and untidy spreading small tree reaching up to 8m high. The old stems are twisted and furrowed with flaking bark. Dull greyish-green, leathery leaves with rounded tips which end in a tiny point. Solitary white flowers appear from August to October. The green fruit capsules turn yellow and then grey.