Pest control hub
What does it look like?
Scrambling or twining perennial with dense clusters of white, fleshy, tuberous roots and twisted, thin, wiry, branched green stems to 3m. Ovalish, pointed leaves (10-35 x 4-15 mm) with 7 veins, one of which appears at each node are actually cladodes (flattened leaf-like stems). Greenish-white flowers (5-6 mm) appear from July to August, followed by round red berries (6-10 mm) each containing 2-8 tiny black seeds. Large leaf-like cladodes distinguish smilax from other Asparagus species.
Has a moderate growth rate, tough, long-lived tubers resprout at will and the plentiful seeds are distributed widely. Tolerates moderate shade to full sun, low to moderate rainfall, salt and wind but prefers good drainage. Birds spread the seeds. Tubers resprout and are spread by soil and water movement. Common sources include roadsides, hedgerows and wastelands.
Why is it a problem?
Forms dense patches and smothers low growing plants and seedlings, usually in low canopy habitats. Can eliminate vulnerable native coastal species. Grows well on poor or volcanic soils, bare rock, sand, coastal and estuarine zone, bluffs, rocks, gumland, pohutukawa forest and inshore islands.
- There is an introduced rust that has been successful in reducing the vigour of this plant.
- Dig out tubers. Dispose of them at a refuse transfer station or burn them or dry and leave on site to rot down.
- Weed wipe (spring-early summer only): 333ml glyphosate (360g /L) per 1L water, no penetrant.
- Spray (spring-early summer only): 200 ml glyphosate (360g/l) + penetrant per 10L water. Do not add penetrant when spraying against tree trunks. Spray lightly, avoiding runoff.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.
What can I do to stop it coming back?
Tubers resprout after spraying and stems break at ground level so plants cannot be pulled out. Grubbing tubers can expose soil, allowing seeds to germinate. Always follow up on treated areas at least 6-monthly. Seeds are probably not long-lived. Replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.