Botanical Name: Rumex sagittatus
Family: Polygonaceae (dock)
Where is it originally from?: South Africa
What does it look like?
Scrambling or low-climbing perennial with brown kumara or beetroot-like tubers (5-20 cm long) with yellow flesh as well as extensive long weak rhizomes. Hairless, reddish-green stems (<3-4 m long) are ribbed, zigzagging and slender. Light green arrow-shaped leaves (3-8 x 2-6 cm) have pointed basal lobes facing downwards. Clusters of small, green-pink or reddish flowers are produced at the top of the plant (Nov-Mar), followed by large masses of showy yellow-pink-crimson, flat, heart-shaped capsules (1 cm diameter) containing seeds.
Are there any similar species?
No other climber has tubers and conspicuous pink seed capsule.
Why is it weedy?
Effective dispersal mechanisms and a fast growth rate allows it to scramble quickly over most plants to 3+ m high. Tolerates damp or drought conditions (dies back to tubers), hot to cool temperatures and most soils, but intolerant of shade.
How does it spread?
Seed and tubers are spread by wind and fresh or salt water, soil movement and vegetation dumping. Common sources are wasteland, hedges, coastal land, heavily disturbed sites and roadsides.
What damage does it do?
Invades regenerating habitats, bare and open sites, replaces low canopy, and prevents the establishment of native plant seedlings. Provides support for more aggressive vines, grasses, etc.
Which habitats is it likely to invade?
Bush and shrubland margins, tussockland, fernland, bare land and dune areas.
What can I do to get rid of it?
- Dig out tubers and rhizomes, small sites only (spring-summer): Dispose of at a refuse transfer station or burn.
- Spray (summer): metsulfuron-methyl 600g/kg (5g/10L + penetrant). Best for follow up after digging out.
What can I do to stop it coming back?
Tubers usually (rhizomes occasionally) resprout after herbicide treatment. Missed fragments resprout after digging. Plant bared sites to minimise seedling invasion.