The following weed profiles are for some of the most invasive environmental weeds in the shire. Thank you to the WA Wildflower Society South West Capes Branch for providing the reference material that much of this information is based.
Unless otherwise stated, photos have been kindly provided by the WA Wildflower Society South West Capes Branch and Friends of Barrett Street Reserve.
Vinca major is a low creeping rambler with large deep blue flowers, growing up to 0.5m tall and spreading up to 10m or more. It is a widely distributed serious weed and pest plant of wetlands, bushland, rivers and gardens throughout Australia and many other countries. It is especially tenacious in WA in moist riparian or wetland habitats.
It spreads vegetatively by rhizomes, stolons and stem fragments to form thick impenetrable mats both above and below ground, that are very difficult to eradicate. It is important where possible to control small infestations quickly as they are so difficulty to eliminate once established. Large swathes are to be seen along the banks of the Margaret River.
Hand pull small infestations, paying attention to removing every fragment of stem and root. Spray larger areas with 2% glyphosate + penetrant (penetrant is essential due to waxy coating on the leaves). Repeat applications will be required every time new growth is visible, this may take years for large infestations.
Note: When using chemicals, always read the label instructions and use only as directed. If required, seek manufacturer advice or refer to the Safety Data Sheet (SDS) for detailed information about the safe use of chemicals.
Patersonia occidentalis, Pimelea ferruginea, Orthrosanthus polystachyus
Pittosporum undulatum is a tall, bushy, dense large shrub or small tree up to 8m tall. It has large green glossy oval leaves, strongly perfumed attractive creamy flowers in spring, followed by bright orange sticky fleshy fruits highly attractive to birds. This is one of our most invasive and widespread weeds.
It’s a highly shade tolerant species which out-competes native plants in the bush, forming exclusive thickets. It’s allelopathic (exudes chemicals toxic to roots of other plants) and is usually unsightly, being infested with a variety of thrips, psyllids etc. It is also Dioecius, with different male and female plants.
Hand pull or dig out seedlings. If too big, cut to the base and paint with herbicide. In large infestations, prioritise removal of fruiting trees.
Note: When using chemicals, always read the label instructions and use only as directed. If required, seek manufacturer advice or refer to the Safety Data Sheet (SDS) for detailed information about the safe use of chemicals.
Hakea lasianthoides, Hovea elliptica, Melaleuca huegelii, Agonis flexuosa, Acacia myrtifolia.
There are several species of weedy Pandora Vine. Introduced as a garden plant, where it can also be a pest, this very vigorous Australian wet or dry rainforest woody vine is emerging as a very serious environmental weed in our area. When established it can smother large areas of native bush and climb to the tops of the tall karris. Seeds are spread via wind or water and seedlings come up as thickly as grass over a large area, totally excluding indigenous species. Stems will also make roots where they touch the ground (layer), making a dense mat of vegetation that excludes all light and moisture, totally eliminating other vegetation.
Pandorea vines are evergreen, vigorous climbers with bright green foliage. One of the more common species, Pandorea pandorana (Wonga Vine) has cream to white or occasionally yellow, narrow bell shaped flowers, often flecked with red or dark brown inside, in late winter/spring. Another common species, Pandorea jasminoides (Bower Vine) has large, tubular flowers that are usually pale pink with a deep pink throat between spring and late summer.
A long lived plant, Pandorea sp. are tolerant of temperature extremes and drought and thrive when summer temperatures are higher.
Spray with herbicide plus surfactant all year round, or cut and paint. Will resprout, so repeat control is necessary. Remove all growth from the site or burn, as it will take root and regrow.
Note: When using chemicals, always read the label instructions and use only as directed. If required, seek manufacturer advice or refer to the Safety Data Sheet (SDS) for detailed information about the safe use of chemicals.
Hardenbergia comptoniana, Kennedia prostrata, Clematis pubescens
Asparagus scandens is a creeping or climbing vine with delicate, feathery leaves giving a fern-like appearance. It is a tuberous perennial with a thornless, wiry stem that grows vigorously over winter and resprouts from tubers.
This is a significant environmental weed in the Margaret River Region, and poses the greatest risk to our river riparian zones. Its tuberous root system forms a dense mat that prevents native seedlings from germinating, and its climbing stems can smother small understorey plants. It is related to another serious environmental weed, bridal creeper (Asparagus asparagoides).
Remove isolated seedlings by hand, ensuring underground parts are destroyed. May be killed by crowning i.e. cut and scoop out centre of plant. Weed wipe glyphosate at 50%, repeat in 6 months, or spray at 100ml +1g metsulfuron methyl+25ml Pulse® in 10L water.
Note: When using chemicals, always read the label instructions and use only as directed. If required, seek manufacturer advice or refer to the Safety Data Sheet (SDS) for detailed information about the safe use of chemicals.
Centella asiatica, Dampiera decurrens.
This is an evergreen shrub or small tree up to 6m tall, with young stems exuding a whitish, irritant sap. Leaves are ovate to heart shaped, often reddish as they age or in cool weather, smooth or may be slightly hairy, underneath greyish. It flowers in spring/summer and bears fleshy fruits from December-March.
A shade tolerant pioneer species, this is becoming widespread around townsites, degraded sites and in bush adjacent to the Margaret and Blackwood Rivers. Birds spread seeds into good condition bush. The plant contains latex which can be a skin and eye irritant, and leaves are toxic to many mammals.
Hand pull young plants and seedlings, wear gloves and protective clothing. Cut and paint stump of larger plants immediately with 50% glyphosate.
Note: When using chemicals, always read the label instructions and use only as directed. If required, seek manufacturer advice or refer to the Safety Data Sheet (SDS) for detailed information about the safe use of chemicals.
Thomasia triphylla, Templetonia retusa, Chorilaena quercifolia, Beaufortia sparsa
