Cat’s Claw Creeper (Macfadyena unguis-cati) is an exotic weed vine that threatens Brisbane’s waterways and bushland areas. In a bid to target a single species, thus focussing efforts city wide, Brisbane Catchments Network (BCN) has proposed control and eradication of Cat’s Claw everywhere it exists within Brisbane Catchment.
The first stage of the project is to map the occurrences of Cat’s claw within Brisbane Catchment, then follow up with control methods and reviews.
There was a workshop to trial a new ‘user-friendly’ weed mapping methodology on 10th of February 2007 at the Silky Oak Picnic Area, Sir Samuel Griffith Drive, Mt. Coot-tha.
Scientists at the Alan Fletcher Research Centre (AFRS) are currently investigating potential biological control agents, including the Leaf-sucking Tingid Bug, Carvalhotingis visenda (a native to Brazil and Argentina imported to Australia in 2004). C. visenda lays eggs only on cat’s claw creeper, then nymphs develop and feed only on cat’s claw creeper, causing severe leaf damage
Another possibility being studied is the leaf-tying pyralid moth, Hypocosmia pyrochroma. This moth was originally collected from Brazil and Argentina, imported from South Africa in 2005. The moth’s larvae cause severe leaf damage (only on cat’s claw creeper).
Climate matching indicated that conditions present in native range areas of northeast Argentina, south Brazil, Uruguay and Paraguay most closely matched the conditions where heavy infestations of cat’s claw creeper were found in Australia. A genetic study tested plant material from cat’s claw creeper introductions in Australia to determine where they originated in the native range, which extends from central America to Argentina. The results indicated the cat’s claw creeper found in Australia mostly originated from the southern extent of the species’ native range.
Future possibilities include the Leaf-sap feeding tingid (Carvalhotingis hollandi), Leaf-feeding jewel beetles (Brachys sp.) and the seed-feeding weevils (Curculionidae sp).
SOURCE: Alan Fletcher Research Station.
The Cat’s Claw problem
In Australia M. unguis-cati occurs in coastal and subcoastal Queensland and New South Wales. In Queensland M. unguis-cati occurs in 61 shires and in 32 shires infestation levels of the weed are on the increase. In NSW M. unguis-cati occurs in five of the subdivisions in the northern coast. Cat’s claw creeper has the potential to spread along the entire eastern coast.
Cat’s claw creeper is a serious threat to biodiversity in riparian and rainforest communities in eastern Australia. It is a high climbing woody vine, with stems to 6 cm in diameter and roots becoming elongated-tuberous with age. The plant flowers in spring and the seeds are dispersed by wind and water (Vivian-Smith & Panetta, 2004). It thrives in full sun or partial shade and in a wide variety of soils and also produces stolons and root tubers, which grow vigorously and produce dense mats on the forest floor. It climbs over standing trees in vine scrubs, gallery forests, rainforests, closed forests and open forests. Trees can be crushed by the weight of vines, allowing further light to enter the forest and promoting invasion by more light-demanding species. Furthermore, M. unguis-cati infestations may cause an inward collapse of the forest margin, as individual trees are colonised and killed.
SOURCE: Alan Fletcher Research Station