Arum lily
Botanical Name
Zantedeschia aethiopica
Family
Araceae (arum)
Also known as
Death lily
Where is it originally from?
South Africa
What does it look like?
Evergreen, clump-forming tuberous herb (<1.5 m tall), with new tubers arising from shoots on the rootstock. Dark green, arrow-shaped leaves are large and leathery. Produces large white flower with a yellow spike and yellow-green berries (10 mm).
Are there any similar species?
Italian arum (Arum italicum) is similar and is also weedy, but has distinctive white veins on the tops of the leaves.
Why is it weedy?
Long-lived and persists under regenerating canopy, forming dense patches excluding other vegetation. Tolerates wet, wind, salt, hot to cold, most soil types and moderate shade, and is drought-resistant once established. Stock avoid it as it is poisonous, allowing it to gradually dominate grazed sites.
How does it spread?
Seeds drop near to parent plants, and are occasionally spread by birds and water. Clumps expand slowly by new shoots, and tubers and seed are spread by dumped vegetation and soil movement.
What damage does it do?
Smothers the ground preventing the establishment of native plant seedlings. It is unlikely to poison native fauna.
Which habitats is it likely to invade?
Swamps, open damp areas with low cover, and regenerating ex-pasture, especially downstream or adjacent to infested areas.
What can I do to get rid of it?
1. Physical removal - Hand pull or dig out entire plant - Ensure all plant material is removed from site to prevent regrowth and dispose of to a refuse transfer station. Tubers can be dried out and burnt.
2. Cut and paste - Cut the stem/trunk as close to the ground as possible and cover the entire stump with herbicide as soon as possible after cutting. Apply glyphosate + metsulfuron gel to the entire cut stem.
3. Foliar spray - Apply herbicide using a hand held sprayer/knapsack. Apply a mix of Glyphosate (360 g/L active ingredient) herbicide at 15ml/L + metsulfuron herbicide (600g/kg active ingredient) at 0.3g/L + an organo silicone penetrant such as 'pulse' or 'boost' at 1ml/L and thoroughly wet all parts of plant. Note: Overspray will kill other (desirable) broadleaf plants and has residual activity in the soil which aids in killing below ground parts. Do not use over or near water bodies or wetlands and use only as directed on label.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Mowing gives no control. Digging usually leaves root fragments and dropped tuber pieces which resprout. Small infestations may be left untreated where regeneration to dense forest is occurring, however removal of arum will increase native seedling establishment rate. Exclude all livestock from site when treating.