Spider gum

Eucalyptus conferruminata

Spider gum is a small tree with smooth, whitish grey bark. Yellow-green flowers appear from late winter to late spring. It is an attractive, medium-sized shade or screen tree. It is usually multi-trunked with light green, fragrant foliage. It prefers coastal conditions, where it tolerates dry winds and salt spray.

Spiked water milfoil

Myriophyllum spicatum

Spiked water milfoil is a submerged aquatic plant that can rapidly take over a pond, lake or area of slow-moving water. It creates dense mats of vegetation that shade out other indigenous aquatic plants, diminish habitat and food resources valuable for fish and birds, and decrease oxygen levels in the water when the plant decays.

Spiny cocklebur

Xanthium spinosum (Asteraceae)

A many branched annual growing up to 1,2m high. Yellowish or brownish-grey, downy stems. Green leaves which are densely white-woolly beneath and sparsely downy above. Each leaf base is armed with a yellow, three-pronged spine up to 2cm long. Pale yellowish burrs covered with spines.

Sponge-fruit saltbush

Atriplex inflata

Low softy woody shrublet 0.2- 0.4(-0.7) m high creamy - white branches. Leaves are grey to bluish-green, scaly, about 2x longer than broad, margins smooth or slightly wavy and toothed. Flowers: cream to yellow, minute, in tight axillary cluster at the ends of leafy stem. Fruits are utricles, grey-green turning pink or straw- coloured, spongy and inflated, sub-globose, upper surface flattened, up to 10 mm long and wide. 

Spreading century plant

Agave Americana

Succulent shrub with a basal rosette of thick, heavy leaves up to 2 m high; suckers from the base; flowering pole 5-9 m tall. Leaves light grey, with toothed margins and terminal spine; leaves reflexed (as opposed to unreflexed in variety expansa); variegated forms have grey to dark green leaves with yellow or white margins and a central stripe.

St. John's wort

Hypericum perforatum (Hypericaceae)

Erect, softly woody perennial distinguished from indigenous Hypericum spp. by its creeping underground stems. It produces many slender, erect stems up to 1m high in summer and spreading, prostrate stems in winter. Light green leaves with translucent oil glands. Bright yellow flowers with black oil glands on the margins of the petals from October to January. This plant is poisonous.


Limonium sinuatum

Statice is a perennial herb reaching 400mm high with densley hairly stems and leaves. The leaves are in a basal rosette up to 100mm long and 30mm wide. The flowers are pink or violet to purple, or even white or yellow.

Stink bean

Paraserianthes lophantha (Fabaceae)

A fine bi-pinnate leaved evergreen shrub or tree growing 4-6m high, somewhat resembling the large-leafed black wattle (Acacia mearnsii). The dark green leaves are paler below, up to 300 mm or longer and golden-hairy. Cream-coloured flowers appear in dense, bottlebrush-like heads from June-August followed by brown compressed seed pods with raised edges. The seeds emit a nauseating odour when crushed and this tree is poisonous. It invades forest margins, river banks, moist slopes in fynbos and wooded kloofs.

Stinking weed

Senna occidentalis

A smallish shrub or erect herb growing 50cm-2m high. The vivid green leaves occur as leaflets usually in 4-5 opposite pairs, which are lance-shaped to elliptical and 40-100mm long. Pale yellow flowers in 2-4 flowered axillary racemes during the summer months. It is competitive and poisonous and competes against indigenous species. Crushed parts have an unpleasant smell lending it the common name of stinking weed.

Strangler prickly apple

Harrisia balansae

A very rare cactus with menacing looking but beautifully symmetrical spines. By summer it produces large white flowers reaching about 25 cm in diameter. The flowers are whiter then fall off to produce bright red edible fruits.Strangler prickly apple has been recorded only in two provinces of South Africa, North West and Limpopo.