Elephant grass is a robust perennial grass widely naturalised in tropical and subtropical regions of the world. It has low water and nutrient requirements and therefore can thrive in otherwise uncultivated lands. It is an aggressive grass that grows rapidly, colonising new areas and forming dense thickets. It grows in summer.
English ivy is an evergreen climbing vine. It is an aggressive invader that threatens all vegetation levels of forested and open areas, growing along the ground as well as into the forest canopy. It is widely used as a fast-growing, low maintenance, evergreen groundcover and climber but, once established at a site, it can be expected to move beyond its intended borders by vegetative means or by seed dispersal.
Annual herb growing up to 1,5m high with an erect, longitudinally grooved, hairy stem and deep tap root. It has pale green, hairy leaves and small white flowers in compact heads, appearing from September to May. The whole plant is a skin and respiratory irritant. It invades roadsides, rail sides, water courses, cultivated fields and overgrazed land.
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A sparsely branching, perennial grass which is open and creeping with feathery, spike-like inflorescences. The bristles are long and detach with the spikelets. Leaves are up to 40cm long and are not rigid or ending with sharp points. Inflorescence 40-70mm long and is white or light brown. This grass invades roadsides and disturbed sites and has a preference for colder areas.
The Formosa firethorn is an evergreen shrub with spiny branches and glossy green leaves. White flowers appear in spring, followed by bright red berries. It can form dense thickets, which compete with indigenous vegetation and impede the movement of animals and people.