Rust fungus on smilax.
Source: Environment BOP Biocontrol agent:
Smilax – also known as bridal creeper or bridal veil creeper
What does rust fungus look like?
Rust fungus is thought to have been self-introduced to New Zealand from Australia. Infection by the rust results in yellow circular blotches on the leaves and leads to leaf dieback.
Where is it established?
Rust fungus has recently been discovered in Northland in the Whatitiri area, west of Whangarei (Norris Rd off Whatitiri Rd).
When and how is it harvested for redistribution?
The smilax rust is currently designated as a new organism under the HSNO Act, so is not available for redistribution until this has been changed.
About the target weed pest:
Smilax is a scrambling or climbing perennial vine with twisted, wiry stems and white, fleshy tuberous (tubers are underground stems) roots in clusters. The leaves are almond- shaped with one at each node on the stem where a leaf or bud grows out. Small, greenish-white flowers occur where ‘leaves’ join the stem, and can be present from July to August. The flowers are followed by round, red berries containing two to eight tiny black seeds.
Smilax smothers low growing plants and seedlings, forming dense patches and can eliminate coastal native species. It is tolerant of sun, shade and low rainfall and prefers to grow in low, disturbed forests and forest margins, in waste places, hedgerows, on roadside banks and in coastal places. Smilax produces a lot of seed which is dispersed by birds. The tubers are tough, long-lived and will re-sprout if moved elsewhere.