Trichocereus spachianus (=Echinopsis spachiana) (Cactaceae)
A spiny, multi-stemmed succulent plant up to 1,5m high with numerous spines in groups of 8-10, amber-coloured turning grey. Central spine is longer than the radial spines. No leaves. Showy white nocturnal flowers appear from November to March. The floral tube is covered with long hairs. This cactus produces green hairy fruits with black seeds. It invades dry savanna and Karoo.
Montanoa hibiscifolia (Asteraceae)
A perennial half-shrub growing up to 6m high with dark green, large, palmately-lobed leaves which are paler beneath and softly hairy on both surfaces. The flower petals are white and the disc yellow and are borne in terminal clusters from May to October. Reddish-brown fruits borne in the rounded, papery old flowerheads. It invades forests, woodlands, bush clumps, roadsides, river banks and disturbed sites.
Tree mallow is a shrub that grows up to 3m high with a stem which is greyish white and a woody base.The leaves are velvety hairy up to 200mm long, shaped like an open palm, lobed with five to nine lobes. Flowers are bright pink or lilac with dark veins and throat 30-40mm across in clusters of 2-7 that grow out from leaf axiles.
The tree tomato is a small tree or shrub indigenous to the Andes Mountains. Significant production of the fruit occurs in New Zealand, which exports it along commercial channels. It has invaded forest margins and understoreys in KwaZulu-Natal and the Eastern Cape.
Ailanthus altissima (Simaroubaceae)
A fast growing tree from China can grow 20m or more. It has smooth stems with pale grey bark, and twigs which are light chestnut brown, especially in the dormant season. In late spring, clusters of small, yellow-green flowers appear near the tips of branches. Seeds are produced on female trees in late summer to early autumn. Fruits are papery, somewhat twisted, winged structures called samaras that are tan to pink-coloured.
Chromolaena odorata (Asteraceae)
Scrambling, sparsely hairy shrub up to 4m or higher, often forming dense thickets with wide-spreading branches. Light green leaves, often yellowish which smell strongly of turpentine or paraffin when crushed. White or pale blue cylindrical flowers appear from June to July. It produces straw-coloured, bristly fruits and this plant is poisonous.
Invades: Forest margins, savanna, plantations, wooded kloofs, water courses, roadsides
Tropical water fern
Azolla cristata tropical
Roots3--5 cm.Stems prostrate, 1--3 cm, or nearlyerect, 3--5 cm,hairs absent. Leaves with 1(--2) -celled hairs on upper surface of upperlobe.Sporocarpsin pairs. Megasporocarp megaspore with 3floats. Microsporocarp masses entirely covered with arrowlikebarbs.
Tumbleweed is an annual weed that begins life as a typical multiple branched bushes, which then takes on a spherical form. It depletes soil moisture and interferes with cultivation operations. This species invades roadsides, disturbed sites, riverbanks, riverbeds, in dry or somewhat saline areas. Flowering occurs from September-April.
Tussock paspalum is a coarse perennial grass, 2 m high, growing in large bluish-green bunches. Rhizome short, stem compact. Leaves with longitudinal prominence on the back, 15-40 cm long and 5-8 cm wide. Flowers in clusters of 40, rust coloured, 12-30 cm long. Flowers and seeds produced twice a year.
Pinus pinea (Pinaceae)
A coniferous tree 12-30m high forming an umbrella-shaped crown with dense foliage at maturity. The trunk is straight, often forking with reddish-brown bark and deeply cracked into plates. Light green leaf needles in bundles of two. Nut-brown, woody cones 10-15cm long. It invades grasslands and mountain fynbos.