Special note: Self-introduced biocontrol rust is present in the Whangrei Heads area. Most obvious signs of impact usually in July August.
How to Control:
- Dig out tubers. Dispose of them at a refuse transfer station or burn them. Leave foliage on site to rot down.
- Weed wipe spring-early summer (300ml glyphosate/1L water).
- Spray in spring-early summer: cut vines 60cm above ground, spray lightly, avoiding runoff, with (200ml glyphosate + 20ml penetrant/10L water). Do not add penetrant when spraying against tree trunks.
Stems break at ground level so plants cannot be pulled out.Tubers can resprout after spraying. Spray regrowth after 2 months. Follow up every year until seed bank exhausted (seeds probably not long-lived). Grubbing tubers can expose soil, allowing seeds to germinate.
Replant treated areas where possible when control is achieved after 2-3 treatments to establish dense ground cover and minimise reinvasion. Grubbing tubers can expose soil, allowing seeds to germinate.