Family: Ranunculaceae

Status:

Description:
A spreading groundcover, which can form extensive mats in wet areas. Leaves are divided into three toothed or lobed segments, often with pale markings towards the base of the segments, usually on a long leaf stalk (up to 35cm). Flowering stems are often branched and leafy. The flowers are bright yellow and about 1.5 to 3 cm across, with 5 glossy, almost plastic-like petals. Fruits consist of a cluster of small disc-like achenes attached to a central column. However, seed is seldom produced and most spread is from stolons (above ground runners, like those of a strawberry).

Preferred habitat and impacts:
Moist situations are preferred, in anything from full sun to dense shade . Tolerates occasional flooding and waterlogging. Often found in ditches and small creeks with little flow.

Creeping buttercup will form dense mats which smother all native groundcover vegetation and could prevent regeneration of trees and shrubs. Many members of the Ranunculus family are poisonous and all Ranunculus should be regarded as suspect in this regard.

Dispersal:
Broken off sections of plant could take root. Seed or plant fragments spread down waterways by floods, and into other moist areas by dumping of garden waste.

Look-alikes:
There are many native buttercups (Ranunculus species), but none are as robust as creeping buttercup, though many have flowers which are virtually identical. Those associated closely with water are usually quite small with leaves deeply dissected and only 2-3cm across and the flowers with widely separated petals. Ranunculus amphitrichus and Ranunculus inundatus are the most common of these. Other species are found in grass in woodland or forest, and these are more similar to creeping buttercup in leaf and flower shape, but are generally not closely associated with water, and are single erect plants, not clump forming.

An unrelated native herb, Geum urbanum, in the rose family, has very similar lobed leaves, though often with more than three segments. The flowers are 5-petalled, yellow and quite similar to those of buttercups. The fruits are distinctive, consisting of a spherical cluster of achenes attached to a central column, but with each tiny achene bearing a hooked hair-like style up to 10mm long. The whole fruiting structure is a burr, with the structure breaking up and achenes attaching to clothing with their hooked styles. Ranunculus do not do this, although there is usually a tiny hook attached to one end of the flattened, disc-like achene. Geum occurs in wet sites on the tablelands, but is uncommon on the coast.

Control:
Do not plant this species, or if it is already present on your property, do not dump unwanted material where it could re-grow.

Small infestations can be dug out, but fragments of stem can potentially re-grow so removal needs to be very thorough. This could cause erosion in streambank situations. In sunny situations, covering the plant with plastic sheeting for 6 weeks in the warmer months will weaken the plant. After removing the plastic any regrowth can be dug or sprayed. This method will not work in full shade. No herbicides are registered for creeping buttercup.

If treating riverbank infestations, it may be necessary to plant native vegetation after treatment, to prevent erosion. Consult with the Department of Land and Water Conservation before commencing any removal of vegetation on river banks. Remember that there are restrictions on the use of herbicides in watercourses.