Are Your Garden Plants Going Bush? Many common garden plants can invade our bushland and recreation areas in the ACT and region. When Is A Garden Plant A Weed? Weeds are plants growing in locations where they are not desirable or wanted. Many commonly grown garden plants have already spread from the confines of our yards, ponds and aquariums into rural, natural and open space areas causing environmental damage and requiring expensive control actions. These plants are referred to as ‘garden escapes’. Garden escapes may be either natives that have been planted outside their natural range, or plants which have been introduced from overseas. Some garden escapes are already well established in natural areas, but others are in the early stages of invasion and could become widespread unless we stop them now. How Do Garden Escapes Spread? Most garden escapes invade our open space and natural areas by the spread of seed. Your garden may be a major source of garden escapes which are being spread without you realising it. Birds can spread seeds in their droppings after eating the fruit from berry-producing plants like privet and cotoneaster species. Wind and water also disperse seeds. Some garden escapes establish and reproduce from stems, bulbs or corms after being dumped as garden waste on roadsides, parkland or bushland. Weed Swap Program The Australian Native Plants Society and the ACT Government offer a free Weed Swap Program twice a year in spring and autumn. You can dig up your garden escapes and swap them for a native plant. Garden Escapes – A Serious Threat We are fortunate in the ACT and region to live close to natural areas and our visitors also admire the reserves and open spaces that make Canberra the ‘Bush Capital’. If we want to protect these natural areas and open spaces, we must be responsive to the potential harm that garden escapes can inflict on our native flora and fauna. Garden escapes may cause problems by smothering native plants, preventing natural regeneration or by changing the natural balance of resources for native animals such as birds, mammals, reptiles and invertebrates. Controlling garden escapes is an important part of managing our natural heritage and costs the community millions of dollars every year. This brochure has been produced to help you identify plants that can escape from your garden. If we act now, we can keep our natural areas intact. Every individual and corporate citizen has an important role to play. You can help by removing these plants from your garden or avoid planting them. Control Methods Most weeds included in this brochure can be controlled by hand pulling, digging out or cutting down. Registered herbicides are available for spraying leaves or painting stumps. Contact your local ‘Bush Friendly’ garden centre for information on chemical control. It is important to dispose of garden waste in a manner so as not to spread weeds further. Seed-free foliage can be safely composted or delivered to green recycle centres. Seed heads, bulbs, corms and stems that regrow should be sealed in a bag and disposed of responsibly. Alternatives for Garden Escapes An important part of preventing garden escapes from invading our bushland and recreation space is to remove those plants with the potential to escape from your garden and replace them with plants that do not pose a problem. Your local ‘Bush Friendly’ nursery can advise you on replacement plants for garden escapes suited to your situation and requirements. Not the Only Ones The garden escape species included in this brochure are not the only problem plants in the Canberra region. The following plants also have the potential to escape from your garden if left unchecked. Though these plants are not a major problem in the Canberra region at the moment it is recommended that these species be treated with caution. Gazania Gazania species South African Daisy Osteospermum species Chinese Pistachio Pistachio chinensis Butterfly Bush Oenothera species Olives Olea species WA Bluebell Creeper Billardiera heterophylla Bush Friendly Nurseries Many nurseries in the ACT and region have agreed to be ‘Bush Friendly’ and help prevent the spread of garden escapes by not selling any plants included on this brochure. Please support those nurseries that support the scheme and purchase your plants from nurseries displaying the ‘Bush Friendly’ sign. Aquatic Weeds Parrots Feather Species: Myriophyllum aquaticum Family: Maloragaceae Origin: South America Dispersal: vegetatively and from aquarium escape Invades: rivers, wetlands and lakes Cabomba Species: Cabomba caroliniana Family: Cabombaceae Origin: North America Dispersal: by vegetative parts Invades: rivers, wetlands and irrigation channels Salvinia Species: Salvinia molesta Family: Salviniaceae Origin: South America 2 Dispersal: vegetatively spread by water and aquarium escape Invades: rivers and wetlands Delta Arrowhead Species: Sagittaria platyphylla Family: Alismataceae Origin: USA Dispersal: mainly by seed Invades: lakes, reservoirs, ponds Water Hyacinth Species: Eichornia crassipes Family: Pontederiaceae Origin: South America Dispersal: by vegetative parts Invades: rivers, wetlands and irrigation channels Alligator Weed Species: Alternanthera philoxeroides Family: Amaranthaceae Origin: South America Dispersal: vegetative parts spread by water, wildlife and by people. Sometimes mistaken for the garden plant Mukunu-wenna. Invades: rivers and wetlands and irrigation chanels Creepers And Climbers English Ivy Species: Hedera helix including the Canary Island subspecies Family: Araliaceae Origin: Europe Dispersal: by birds and vegetatively from dumped garden refuse Invades: dry forest, heathland, river corridors and neighbours gardens Japanese Honeysuckle Species: Lonicera japonica Family: Caprifoliaceae Origin: Eastern Asia Dispersal: by birds and vegetatively from dumped garden refuse Invades: moist sites in forests, woodlands, gullies and neighbours gardens Wandering Jew Species: Tradescantia albiflora Family: Commelinaceae Origin: South America Dispersal: vegetatively from dumped garden refuse Invades: wet forests, gullies and neighbours gardens Blue Periwinkle Species: Vinca major Family: Apocynaceae Origin: Mediterranean Dispersal: vegetatively from dumped garden refuse Invades: moist forest gullies and neighbours gardens 3 Herbs And Grasses Common Horsetail Species: Equisetum arvense Family: Equisetaceae Origin: northern hemisphere Dispersal: from spores and rhizomes Invades: wetlands, low-lying wet areas and grasslands Pampas Grass Species: Cortaderia selloana Family: Poaceae Origin: South America Dispersal: seed, underground roots and vegetatively from dumped garden refuse Invades: dry forests, woodlands, grassland and heathlands Bamboo Species: Phyllostachys aurea Family: Graminae Origin: South-east China Dispersal: vegetatively from dumped garden refuse, running rhizomes Invades: wide variety of plant communities and neighbours gardens Mexican Feather Grass Species: Nassella tenuissima Family: Poaceae Origin: South America Dispersal: seed Invades: dry and wet forests, woodlands, grassland and heathlands Shrubs And Trees Cootamundra Wattle Species: Acacia baileyana Family: Mimosaceae Origin: limited localities in New South Wales Dispersal: seed spread by birds, ants and water Invades: dry forest and roadsides, particularly disturbed sites or after bushfire English Broom Species: Cytisus scoparius Family: Fabaceae Origin: Europe Dispersal: seed spread by machinery, water, animals and people Invades: river corridors, dry forests, woodlands Cape Broom Species: Genista monspessulana Family: Fabaceae Origin: Europe Dispersal: seed spread by machinery, water, animals and people Invades: dry forest and woodland 4 Lombardy Poplar Species: Populus nigra ‘Italica’ Family: Salicaceae Origin: Italy Dispersal: by suckers and vegetative parts moved by water Invades: river corridors, gullies and moist sites White Poplar or Cottonwood Species: Populus alba Family: Salicaceae Origin: Europe, Western Asia, North Africa Dispersal: by seed, suckers and vegetatively Invades: rivers, wetlands, moist sites and neighbours' gardens Tree of Heaven Species: Ailanthus altissima Family: Simaroubaceae Origin: China Dispersal: by suckering and seed Invades: dry forest and woodland False Acacia Species: Robinia pseudoacacia Family: Fabaceae Origin: Eastern North America Dispersal: by water and vehicles and suckers Invades: native grasslands, dry forests and neigbours gardens Nettle Tree Species: Celtis australis Family: Ulmaceae Origin: Mediterranean to South-western Asia Dispersal: by birds Invades: dry forest and woodland Common or Black Alder Species: Alnus glutinosa Family: Betulaceae. Origin: Europe and Asia Dispersal: seed spread by wind and water Invades: cold damp sites around lakes and river corridors Privet Species: Ligustrum lucidum and Ligustrum sinense Family: Oleaceae Origin: China Dispersal: by birds Invades: moist sites and river corridors Radiata or Monterey Pine Species: Pinus radiata Family: Pinaceae Origin: South-western North America Dispersal: seeds spread by wind Invades: wide variety of plant communities 5 Willows Species: Salix species Except S. babylonica, S. x calodendron and S. x reichardtii Family: Salicaceae Origin: Western Asia, Europe, North and South America Dispersal: seed and vegetatively Invades: river corridors and wetlands Firethorns Species: Pyracantha species Family: Rosaceae Origin: South-western China to Eurasia Dispersal: by birds Invades: forests, woodlands and parklands Gorse or Furze Species: Ulex europeus Family: Fabaceae Origin: Europe Dispersal: spread by vehicles, ants and water Invades: wide variety of plant communities Box Elder Species: Acer negundo Family: Aceaceae Origin: North America Dispersal: seed spread by wind Invades: river corridors and woodlands Hawthorn Species: Crataegus monogyna Family: Rosaceae Origin: Europe Dispersal: by birds Invades: forests, woodlands and creek corridors Spanish Broom Species: Spartium species Family: Fabaceae Origin: Mediterranean and Canary Islands Dispersal: spread by ants, water, machinery, vehicles and soil Invades: dry forests Cotoneasters Species: Cotoneaster species Family: Rosaceae Origin: Eurasia Dispersal: by birds Invades: forests, woodlands and parklands Service Tree Species: Sorbus aucuparia and Sorbus domestica Family: Rosaceae Origin: Western Asia, Eastern and Southern Europe, North Africa Dispersal: by birds and suckers Invades: woodlands and river corridors 6 Spanish Heath Species: Erica lusitanica Family: Ericaceae Origin: Mediterranean Dispersal: by seed Invades: forests and damper sites in woodlands. Looks very similar to a native heath plant Garden Escapes In The Australian Capital Territory And Region What you can do Make your garden ‘Bush Friendly’ by removing from your garden, any plants named in this brochure. Encourage friends and neighbours to do likewise. Avoid planting potential garden escapes. Choose plants from your local ‘Bush Friendly’ nursery which has agreed not to sell these plants. Look for the ‘Bush Friendly’ sign. Join your local ParkCare or Landcare group to assist in a united effort to control garden escapes in your local area. Do not dump garden prunings or refuse on roadsides, open spaces or in parkland areas. Take care not to spread plants via seeds in compost or mulch. Never dump aquarium or pond plants in waterways or wash down drains. Further Information Canberra Connect: 13 22 81 ACT Parks and Conservation Service Territory and Municipal Services Website: www.tams.act.gov.au Australian Native Plants Society website: www.nativeplants-canberra.asn.au PO Box 217 Civic Square ACT 2608 www.weeds.org.au 7