(Also known as Calla Lily)
Type of weed: Herbaceous weed
A clump-forming, perennial herb growing to 1.5m high with a thick underground stem (rhizome).
The large arrowhead-shaped leaf blades are glossy dark green to somewhat dull, leathery in texture, with a prominent midrib and a tip that is bent downwards or curls towards the underside of the leaf.
The arum-type flower structure has a central spike with tiny, tightly packed pale yellow to orange-yellow flowers. This is surrounded by a white to ivory (or green) funnel-like bract with a pointed, recurved tip. It flowers winter to summer.
Fruit is an oval, yellowish berry about 1cm in diameter.
Arum Lily is poisonous to stock and to children. If swallowed it causes dangerous swelling of the mucous membrane of the mouth and throat. Skin contact may cause eczema.
Arum Lily spreads by both seed and root fragments. There may be 50 – 500 seeds per flower head. The seeds germinate readily, but do not usually remain viable for more than about four months. The seeds are spread by water, birds, foxes, contaminated soil and in dumped garden waste.
Impact on bushland
Arum Lily invades native vegetation, forms thick, dense clumps and achieves dominance along watercourses and swampy habitats. The dense clumps crowd out native species affecting the biodiversity of natural areas, especially by replacing the native understorey. In wet, swampy habitats it impedes water flow.
Lower Blue Mountains. Hazelbrook, Woodford, Springwood, Winmalee, Warrimoo and across the Eastern Escarpment.
Council provides a tool, on its Mountain Landscapes website, to help you choose native alternative plantings. Choose your village, soil, vegetation community and the purpose of your planting, and the tool will give you suggestions.
Seedlings can be removed by hand. Removal of old plants is more difficult. Remove all roots and tubers (vegetative propagules).
Treat plants before they set seed and cut off the flowers to prevent spread by birds.
Follow-up treatments will be necessary.
Do not spray as this treatment is generally not effective.
For key points on these techniques:
- See Weed Control Techniques
- See Risks associated with control