Canberra Sand and Gravel near the end of Southern Cross Drive, West Belconnen or Corkhill Bros at the Mugga Lane Tip.
We now know some plants widely used in Canberra gardens decades ago have a tendency to invade surrounding gardens and bushland.
When birds eat the berries from some of these plants they spread the seed. These seedlings grow quickly and compete with native plants, threatening our ‘bush capital’ and the garden city image for which the ACT is famous.
What can be done?
Weed Swap is a joint initiative of the Australian Native Plants Society and the ACT Parks and Conservation Service to encourage ACT residents to remove environmental weeds from their garden, safely dispose of them and then select a free Australian native plant as an appropriate alternative.
Local Australian native plants grow and flower reliably in the ACT and withstand the extremes of Canberra’s winter frosts and hot, dry summers. Once established, their water requirements are low. Many will attract native birds but they will not invade the bushlands in and around Canberra.
What do I look for in my garden?
The target plants are the environmental weeds including Cotoneaster, Privet, Firethorn, Hawthorn, Broom, Cootamundra Wattle and Honeysuckle. Seedlings can often be found growing along garden fence lines, under powerlines and near other trees and shrubs. They grow vigorously and will spread their branches up and through existing plants, using precious water.
The brochure ‘Are Your Garden Plants Going Bush?’ lists and illustrates the environmental weeds that do the most damage in Canberra’s bush and open spaces. It is available from ACT Parks and Conservation Service depots at 66-68 Grimwade Street, Mitchell and Athllon Drive, Farrer. It is available online: www.tams.act.gov.au and on the Australian Native Plants Society’s (ANPS) website. You can also call the ANPS WEED SWAP co-ordinator on 6258 4724 for assistance in identifying weeds.
Some environmental weeds
The following plants are all ‘Declared Pest Plants’ in the ACT and are no longer sold by ‘Bush Friendly’ nurseries.
Large, prickly evergreen shrub with clusters of small white flowers along spurs of branches in spring. Bright orange berries.
Firethorn berries are spread by birds such as Currawongs, Silvereyes, Blackbirds, Starlings and Indian Mynas. Firethorn is a major thicket-forming weed in woodlands of the Canberra area. These thickets tend to shade out native species.
Evergreen shrub to small tree.
Privet berries (and other berry species) support artificially high Currawong populations during winter. As a result, there is a high spring and summer predation pressure on the hatchlings of other bird species, many of which are in known decline. Some people also suffer from hay fever and other allergies due to the pollen. mall, creamy-white flowers in summer, followed by black berries
Frost-hardy shrub to tree with small white flowers and red berries. Soft green leaves, woolly and grey on the underside.
Cotoneaster berries are spread by parrots and Currawongs. Their numerous leaves made them popular as hedge or screen plants.
Cootamundra Wattle Acacia baileyana
Australian native large shrub to small tree with grey bipinnate foliage and masses of golden ball flowers in winter. Naturally occurring in Cootamundra area.
This wattle is usually spread initially by illegal dumping of garden waste but many have been planted in gardens, parks and reserves. When established trees are burnt there is a rapid increase in wattles to the exclusion of indigenous plants.
Shrub with masses of pea-flowers in spring and summer. Flat, silvery pods turning brown. Some with blue-green leaves.
Mature broom pods twist so the seeds explode away from the plant. Follow-up weeding of seedlings is essential to prevent new infestations.
How do I participate?
You can actively contribute to Weed Swap by removing environmental weeds from your garden (following the advice below). Bring the remains of your environmental weeds to the green waste recycling centre at either Canberra Sand and Gravel near the end of Southern Cross Drive, Belconnen or Corkhill Bros near the Mugga Lane Tip. Then visit the Weed Swap
stall at these locations and select from a range of free local Australian native plant alternatives (complete with advice and instructions).
What free replacement plants will be available?
A range of Australian plants will be available as replacement plants at the WEED SWAP sites including Acacia species (wattles), Callistemon species (bottlebrushes), Correa ‘Dusky Bells’, Grevillea species and Myoporum (boobialla). Other ground covers, climbing plants, small, medium and large shrubs and trees may be included.
How do I remove environmental weeds?
If the plant is small, dig out the entire plant, roots and all. If it is larger, cut it off close to the ground and paint the stump as soon as possible with 360g/L glyphosate herbicide mixed at 1:1 ensuring the chemical is applied to the cambium. It is a common misconception that you have to cut grooves into the stumpcentre (heartwood). There is no live tissue found here, the cambium is where the plant has living tissue.
Always read the chemical label before spraying and wear personal protective equipment.
Firethorn Pyracantha, Cotoneaster, Broom Cytisus and Genista sp., Gorse Ulex europaeus and Privet Ligustrum sp.
Cut down to ground level and immediately dab glyphosate/water at a ratio of 1:1 on cut surface. Some regrowth may occur—be vigilant on regrowth and re-treat if necessary.
Hawthorn Crataegus sp.
Cut down to ground level and immediately dab glyphosate 1:1 on cut surface.
Periwinkle Vinca sp. and Honeysuckle Lonicera sp.
Spray with glyphosate at 10ml/L with a few drops of dishwashing liquid to help the chemical ‘stick’ to the stems and leaves. Spray any regrowth with the same mixture.
Grasses: Serrated Tussock Nassella trichotoma, Chilean Needle Grass Nassella neesiana, African Lovegrass Eragrostis curvula
Foliar spray with glyphosate at 10ml/L when plants are highly identifiable. Do not spray plants if frosty. Ensure follow up treatment occurs on a yearly basis until seed bank in soil is exhausted.
Please note: the glyphosate referred to is the commonly available 360g/L product.
Call Canberra Connect on 13 22 81 of visit www.tams.act.gov.au
Australian Native Plants Society visit www.nativeplants-canberra.asn.au