Weeds around the Lake
What some people don't realise is that there are a number of plants around Bibra Lake. Many of them are quite beautiful too. In fact (confession time), we even prominently displayed one on the Gallery page before it was drawn to our attention.
Weeds can be significant at a property, local, regional, state and/or national level based on their impact or potential impact. There are a number of recognised 'lists' of weeds of national interest. The nature of the weeds, and the resulting national actions required, determine on which lists a species may appear.
DAFWA serves to protect Western Australia’s agriculture by:
- works with landholders, grower groups, community groups and biosecurity groups.
- regulates weeds under the Biosecurity and Agriculture Management Act 2007.
- provides a weed identification service.
- provides a predictive simulation tool called weed seed wizard.
- provides information on weed control, crop weeds, regulated/declared plants and herbicides.
- contributes to social science through weedwatcher.
Arum lily: declared
The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA).
Arum lily (Zantedeschia aethiopica) is a declared pest in Western Australia (WA). This article describes the nature of the plant with links to requirements land owners/occupiers must adhere to and pest control methods.
Arum lily is a robust, dark green, succulent herb, also known as calla or white arum lily. It was introduced to WA from South Africa as a garden plant and subsequently escaped to become established as a weed. It is found in creeks, irrigation ditches and areas of summer-moist land in the higher rainfall south west of WA, often forming large dense clumps.
Arum lily competes with valuable perennial pasture plants on summer land. It has been claimed to cause eczema in humans. Stock deaths have occurred from grazing arum lily.
Arum lily has fleshy roots and forms extensive tubers which store food for future use. The roots when boiled provide a starchy food for some South African tribes, however, they are poisonous when eaten raw.
Arum lily spreads vegetatively by regeneration from tuber fragments and by seeds.
Leaves: The petioles (leaf stalks) are up to 0.4m long and smooth; the leaf blades are thick and fleshy, pointed at the apex with blunt lobes at the base.
Flowers: White to greenish white and tubular flowers, becoming funnel shaped at the top with a slit down one side. Flowering takes place in spring.
Fruit: The berry is oval, yellowish, about 1cm in diameter and contains several round seeds about 3mm in diameter.
The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA). There information can be found here
Brazilian Pepper Tree
Origin: Native of Argentina, southern Brazil and eastern Paraguay.
Flowers/Seedhead: With 5 sepals and 5 petals about 2 mm long. Inflorescences in leaf axils towards the end of branches. Flowers all year round but with the main flush in autumn and a smaller flush in spring.
Description: Sprawling shrub or erect tree to 6 (rarely to 15) m high. Stems single to branched from base, bark grey with vertical cracking on older stems. Leaves 5–22 cm long, leaflets, dark green above, paler below. Fruit 1-seeded. Seeds pale brown, flattened, ovoid, 4–5 mm long
Distinguishing features: Distinguished by branchlets not hanging; leaves and fruits smell peppery when crushed; leaflets 5–17 (often 7 or 9), 1.5–5 cm long, 1–3 cm wide; male and female flowers on separate trees, petals white to cream; fruit almost globe-shaped, 5–6 mm wide, initially green, red when ripe, outer membranous layer separating from next layer at this time.
Dispersal: Spread by seed, mostly by birds and mammals, also by water.
Widely planted as an ornamental and now naturalised in subtropical areas in Australia.
Common in south eastern Queensland, increasing in north eastern NSW and common along the Swan River estuary in WA.
This species is particularly invasive in disturbed areas but will invade a number of natural environments.
Plants may dominate ecosystems preventing growth of native species. A major weed in many sub-tropical countries between 150 and 300 North and South
If you think that they aren't prolific around Bibra Lake have a look at this photo taken around the lake : There's both the Arum Lily and Brazilian Pepper Tree in this photo. We need to be observant and be careful not to do anything to spread these plants and jeopardise our native plants.