FACT SHEET Weed Wa les
Sydney golden wa le tree (Acacia longifolia) Acacia longifolia – cylindrical flower spikes Wa le trees can make a beau ful tree in a garden or along a wind break on a rural property par cularly when in flower, but if they are not na ve to the area they can become a serious weed in your local bushland. Many wa les are good at colonising new areas of land, especially following a disturbance such as fire. They grow quickly and can produce a large quan ty of seed which is spread by birds, insects and water to other areas. Once established they compete aggressively with other na ve plants for water, light and nutrients and can, under op mum condi ons, create dense, almost impenetrable thickets of trees effec vely wiping out all other na ve plants and habitat for na ve animals. Established thickets of trees can be very labour intensive and costly to remove. There are several wa le species which are problema c in the greater Bunbury region, of these the Sydney golden wa le (Acacia longifolia) presents, perhaps, the worst weed risk. Sydney golden wa le is na ve to the east coast of Australia and is most likely to have been introduced to the south west of Western Australia as an ornamental shade tree or soil stabiliser. It has similarly been introduced to South Africa and areas in Europe were it also presents a major weed problem. Management authori es in South Africa use a biocontrol agent to manage the weed. It may be confused with the local na ve wa le Golden wreath wa le (Acacia saligna), but is easily dis nguished by its prominent parallel leaf veins and long cylindrical flowering spikes. Other wa les of concern in the Bunbury region are the Flinders Range wa le (A. iteaphylla), Cootamundra wa le (A. baileyana), silver wa le (A. dealbata), Queensland silver wa le (A. podalyriifolia) and golden wa le (A. pycnantha) all of which are commonly planted ornamental trees. Many land managers including local and state government bodies, not‐for‐profit natural resource management groups and private en es are working hard to control these weeds on their lands.
Golden wreath wa le (Acacia saligna) flower and leaf A. saligna leaf – angled veins. A. longifolia leaf – parallel veins
P: 08 9792 7000 E : [email protected] A: 4 Stephen Street, Bunbury WA 6230, PO Box 21 Bunbury WA 6231 www.bunbury.wa.gov.au FACT SHEET
PLANNINGWeed Wa lesFOCUS
Flinders Range wa le ( A. iteaphylla) Queensland silver wa le (A. podalyriifolia) Silver wa le (A.dealbata) Control Methods Wa les are best controlled as seedlings when they are easy to lever and hand‐pull or over‐spray with a 10% solu on of glyphosate. Mature, larger plants are controlled by felling the tree and then pain ng the freshly cut stump with a solu on of 50% glyphosate to prevent suckering and regrowth of the plant. Alterna vely trees can be poisoned and killed without felling by injec ng them with a 50% glyphosate solu on, or by pain ng the bark around the base of the tree with a 250 ml mix of Access® in 15 L of diesel. Trees are most effec vely controlled using herbicides between March and August. It is im‐ portant that felled trees and branches are removed as they can reproduce vegeta vely by developing adven ous roots where the plant meets the soil. The removed trees can be chipped and used as mulch or the smaller trees and branches can be used as brush to stabilise sand dunes. How can you help? You can help by replacing poten al weed wa les growing on your property with na ve trees or with other species that have less poten al to become weeds in na ve bushland. A list of alterna ve, rela vely hardy, smaller tree species with colourful flowers or leaves is provided in the table below. Please inves gate these for suitability on your property. Other suitable spe‐ cies may be found on the Water Corpora on website at h ps://www.watercorpora on.com.au/save‐water/waterwise‐ Table 1. Alterna ve replacement trees to consider plan ng Common Name Scien fic Name Comments Common Name Scien fic Name Comments
Golden wreath Acacia saligna Na ve SW WA, yellow fl, 5 m. Emu tree1 Hakea francisiana Na ve WA Wheatbelt, pink‐ wa le1 red fl, 3‐8m. 1,2 Bo le brushes Callistemon cul vars Red and pink fl, 4‐8 m. Pin cushion hakea1 Hakea laurina Na ve to south coast WA red fl, 2‐6 m. Red flowering gum1 Corymbia ficifolia Na ve lower SW WA, red fl, 8m. Red co onwood2 Hibiscus liaceus Na ve to Qld & Pacific Eucalyptus summer Cul vars of Corymbia Pink fl (SB) and red fl (SR), 5 m. rubra coasts, yellow fl, 8‐10 m. beauty (SB) & Sum‐ ficifolia Na ve frangipani2 Hymenosporum Na ve to Qld, yellow & red mer red (SR)1 flavum fl, 10m. 1 Silver princess Eucalyptus caesia Na ve WA Wheatbelt, pink ‐ red Crepe myrtle3 Lagerstroemia indica Na ve to eastern Asia decid‐ fl, 2‐ 8 m. uous, pink,red fl, 6‐8m. Coral gum1 Eucalyptus torquata Na ve WA Goldfields, coral fl, 5‐ 3 10 m. Ornamental plums Prunus species Deciduous, na ve Europe & Asia, white – pink fl,8‐10m. Bell fruited mallee1 Eucalyptus preissiana Na ve south coast WA yellow fl, sprawling mallee, 3‐5m. Ornamental pears3 Pyrus species Deciduous, na ve Europe & Ilyarrie2 Eucalyptus eryth‐ Na ve n & s of Geraldton, yellow Asia, white – pink fl, 8‐10m rocorys fl,3‐8m. Chinese tallow3 Triadica sebiferum Deciduous, na ve Eastern Claret ash3 Fraxinus angus folia Deciduous, na ve Europe & Asia, Asia, 8‐12m ‘Raywood’ 8‐10m. 1.WA na ve, 2. Australian na ve, 3. exo c to Australia
supported by Royalties for Regions