- Plant type
- Spreading shrub
- Status in NSW
- Prohibited from sale in NSW. Weed of National Significance. Must be eradicated in the Bitou Bush Biosecurity Zone, which covers inland Nambucca.
Bitou bush is a South African shrub that was planted on NSW beaches after sand mining and now covers large areas of coastal dune. Within 10 km of the coast the aim is to stop it spreading. Further inland it must be reported and removed.
How to identify it
Bitou bush is a woody shrub, usually 1 to 2 metres tall and 2 to 6 metres wide, that can also climb up to 10 metres over other plants. Look for:
- bright green, thick, slightly fleshy leaves 3 to 8 cm long, broadly oval and sometimes lightly toothed, with a cottony fuzz when young
- bright yellow daisy flowers up to 2 cm across, clustered at the ends of the branches, mostly in winter
- egg-shaped berries 6 to 8 mm long that turn from green to purplish-black
Its close relative boneseed is taller and more upright, with fewer petals and round, smooth seeds.
Where it grows
Bitou bush thrives in sandy, low-fertility soils and copes with salt, strong wind, sand blast and drought. On our coast it grows on the dunes and headlands and around estuary and lagoon edges, and it can move into coastal forest and grassland. It does poorly in wet, swampy ground.
Why it's a problem
- It smothers dune plants and can climb over native shrubs and trees up to 10 metres tall.
- In NSW it threatens 55 threatened plant species and 15 endangered ecological communities.
- It reduces food and habitat for native animals and nesting sites for shorebirds.
- Dense stands shelter feral animals and block access to beaches and walking tracks.
How to control it
Combine methods and plan for follow-up. A single plant can produce up to 48,000 seeds a year, and seed in the sand keeps germinating for years.
- Hand pull seedlings and small plants. This is easy in sand, but take the whole root.
- Spray with a registered herbicide. Winter, when it is in full flower, is the most effective time. Avoid spraying plants stressed by heat, cold, dust or salt spray.
- For larger plants, cut and paint: cut low and apply herbicide to the cut within 15 seconds.
- Slash large plants, leave the mulch on site, then spot spray the regrowth.
- Three biological control insects (a tip moth, a seed fly and a leaf-roller moth) are established on the coast and help weaken plants.
Always follow the herbicide label. If you find bitou bush more than 10 km from the coast, report it to your local council weeds officer.
Safety and disposal
- On dunes, work from existing tracks where you can. Disturbed sand blows away and encourages more seedlings.
- Pulled plants can re-root if buried. Leave them on top of the sand to dry out, or bag plants that are carrying seed.
- Wear sun protection and gloves, and follow the label safety directions for any herbicide.
Stopping it coming back
- Replant cleared dunes with local native dune plants as soon as possible, so seedlings have competition.
- Keep vehicles out of infested areas and clean vehicles, boots and equipment before leaving.
- Return to the site every few months, because seed in the sand will keep germinating.
