Environmental Weeds of the

Eastern Hills Region (DRAFT)

50 weeds you should know about

Compiled for our community by

Wooroloo Brook LCDC

Environmental Weeds of the

Eastern Hills Region (DRAFT)

©2002 Wooroloo Brook Land Conservation District Committee. Copyright: No part of this publication can be copied without permission of the Wooroloo Brook LCDC. Contact: peakpot@vianet.net.au Acknowledgements: Thanks go to Zamun Mohammed from the Green Reserve program for his help in compiling the data. Disclaimer: These notes are in draft and therefore are incomplete and are compiled as a guide, from a variety of sources and are not necessarily the views of the Wooroloo Brook Land Conservation District Committee. Main references: Bush Invaders of South-East Australia Adam Muyt ©2001 published by RG and FJ Richardson Southern Weeds and their Control John Moore & Judy Wheeler ©2002 published by the Department of Agriculture WA Other Useful References Western Weeds BMJ Hussey, GJ Keigher5y, RD Cousens, J Dodd, SG Lloyd Has descriptions and photos of nearly all naturalized plants. Available from Agriculture WA and Department of Conservation and Land Management Como. Bushland Weeds – A guide to their management Kate Brown, Kris Brooks Has case studies and good control information. Available from the Environmental Weeds Action Network Or check out the following websites: www.nra.gov.au www.agric.wa.gov.au http://www.calm.wa.gov.au/science/florabase.html

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INDEX

African Lovegrass 5 Lavender 16 Arum Lily 5 Lupin 16 Bamboo 6 Melons 16 Barley Grass 6 Morning Glory 17 Blackberry (Bramble) 6 Nasturtium 17 Blue Periwinkle 7 Nightshade (Blackberry) 18 Blow Fly Grass (Quaking Grass)

7 Pampas Grass 18

Bridal Creeper 8 Patterson’s Curse 19 Brome Grass 8 Poplar 19 Broom 9 Radiata Pine 20 Bull Rush 9 Ryegrass 20 Caltrop 10 Silver Grass 21 Cape Broom 10 Storksbill 21 Cape Tulip 11 Soursob 21 Cape Weed 11 Stinkwort 22 Clover 11 Storksbill 22 Dock 12 Tagastaste (Tree Lucerne) 23 Doublegee 12 Veldt Grass 23 Evening Primrose 13 Victorian Tee Tree 24 Flatweed (Dandelion) 13 Watsonia 24 Freesia, Babinia, Ixia 13 Wattles 25 Fleabane 14 Wild Oats 25 Gladiolus 14 Wild Radish 25 Guildford Grass 15 Willow 26 Lathyrus 15

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Environmental Weed

African Lovegrass

FACTS

• Can seed 5-6 times per year • Road verges & disturbed ground • Difficult to control • Serious fire hazard • Prolific seeder • Found on disturbed sites such as road & rail reserves and sometimes invading bushland • Native to South Africa Control • Smaller plants can be dug out. To prevent regrowth ensure the crown is removed. • Larger infestations can be burnt or slashed. • Plants can be sprayed with non-selective or grass-selective herbicides • Cultivation and rotational grazing usually provides reasonable control • Control for 2-3 years

Environmental Weed

Arum Lily

FACTS

• Declared weed • Usually found in moist areas such as water courses and open rural land • Forms dense stands which crowd out pasture species & native plants • Yellow spike & white flower is poisonous • Toxic to stock & reported to cause death to children • Sap causes eczema • Impedes water flow • Spread by underground storage tubers and berries are spread by birds • Popular garden plant • Often discarded irresponsibly • Still sold in nurseries • From South Africa • Flowers mostly late winter and spring Control • Removal of plants including tubers and roots by hand or digging. • Multiple rotary hoeing over a few years provides control • Cut flowers to prevent birds spreading seed • Encourage control on a district basis to reduce re-infestation. • Herbicides provide the most effective control • In sensitive areas a blanket wiper may be used

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Environmental Weed

Bamboo

FACTS

• Introduced as an ornamental plant & now is a garden escapee • Dispersed vegetatively & by water • Smothers watercourses • Reproduces by dividing clumps, rhizomes (underground stems) or by cuttings from

stems. • Removal is often difficult because of accessibility • From southern Europe, Mediterranean area & Asia Control

Environmental Weed

Barley Grass Barley Grass and Sea Barley Grass

FACTS

• Native to Europe • Weed of crops, roadsides, disturbed and saline areas • Flowers in spring

Control

• Prevent seed set for 1-2 years • Hand weeding • Mowing • Cultivation • Herbicides

Environmental Weed

Blackberry (Bramble)

FACTS

• Declared serious weed • Forms dense prickly scrambling thickets usually along creek lines & wetlands • Birds & other animals spread it by eating the fruit & voiding the seeds • Difficult to eradicate • Spread by seeds (birds & animals) & roots, stems and where arching canes contact the

soil. Also reproduces from cuttings, root parts and offshoots. • Smothers native flora

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• Poor stabilisation of watercourse banks • Harbour for rabbits and other vermin • Fire hazard • From Europe • Flowers in spring and summer Control • For small infestation seedlings and small plants can be dug out when soils are moist. • For larger infestations plants can be treated with selective and non-selective herbicides. • Most of the root system must be removed for effective control. • Burning is not effective apart from allowing better access • Three annual summer applications of herbicide when blackberry is actively growing. • Grazing with goats is reasonably effective • Replant native species after control • Biocontrol rust fungi have established but have had little impact

Environmental Weed

Blue Periwinkle FACTS

• Sprawling groundcover • Blue to violet flowers with a white throat • Garden escape • Sometimes found in dark shady areas • Able to cover large areas by producing roots where the stems are in contact with the

ground. • Naïve to the Mediterranean • Widely cultivated in Australia • Flowers from winter to early summer Control • Rake to lift vines off the ground then mow or cut the vines • Regrowth can be sprayed with non-selective or grass-selective herbicides. Several

applications about three months apart are required. • Spot spray or manually remove the last remnants of plants as these will be the source of

reinfestation. • Hot fires and solarisation provide some control.

Environmental Weed

Blow Fly Grass Quaking Grass

FACTS

• Widespread in granite outcrops, wastelands, wetlands & woodlands. • Seeds germinate in autumn in response to rains and plants grow over late autumn-winter,

then flower, set seed and die off in late spring or early summer.

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• Large populations can rapidly build up as most seed is viable and germinates the following year.

• Large populations can reduce ground-flora species rich-ness in grassy woodlands by over half.

• Summer die-off plants can increase the fire hazard in many grassy ecosystems. • Native of the Mediterranean Control • Plants are easy hand-pull as roots are very shallow. Material without seed can be left to dry

out on-site. • Prevent seed set for 3-5 years • Scorching with gas burner before flowering is effective • Unripe seed heads can be gathered using catcher mowers. Avoid mowing stands with

ripened heads as they shatter and disperse very easily. Infestations can also be mown at the time the first anthers emerge in spring. Cut close to ground level to prevent flowering.

• Burn semi-ripe or ripe seed heads in late spring-early summer using hand-held gas burners. • Plants can be sprayed with non-selective or grass-selective herbicides.

Environmental Weed

Bridal Creeper

FACTS

• Extremely invasive • Urgent environmental weed problem • Forms dense cover smothering everything • Commonly found on roadside verges & creek lines • Is sold in nurseries for hanging baskets. • Produces roots & stems & therefore takes root whenever it comes into contact with the soil. • Can regenerate repeatedly from underground reserves after slashing, burning and spraying • Seeds spread by birds • From South Africa as ornamental plant. Control • Seedlings and small infestations can be dug out. Mats of plant roots should be rolled up and

destroyed. Always monitoring is necessary for re growth over the next year. • Plants can be sprayed with non-selective and selective herbicide. • Biological control: (ie leaf hopper, rust fungus contact CSIRO)

Environmental Weed

Brome Grasses FACTS

• Eleven species in WA • Inhabits native bushland, road reserves and cereal crops • Widespread in disturbed areas • Native of the Mediterranean, South America & Europe

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Control Prevent seed set for 1-2 years Mowing and cultivation

Environmental Weed

Broom English & Flaxleaf

FACTS • Dense evergreen shrub. Produces numerous suckers from a taproot. • Seeds are long lived in the soil and come up after fire before native shrubs can regenerate • Grows rapidly & produces fire resistant seeds. Heavy seeder with seed being spread by

birds, vehicles or stock. • Forms dense permanent thickets. Harbours rodents. Highly in flammable. • Inhabits native bushland & road reserves

Control • Seedlings and smaller plants can be hand pulled or dug out. Tops have tendency to break

away when pulled so if roots remain they should be dug out. • Plants can be treated using the Cut-Paint method.

Plants can be slashed or burnt to stimulate seed germination for follow up control. • Plants can sprayed with non-selective herbicides.

Environmental Weed

Bull Rush Broad -leaved Combungi

FACTS

• Aquatic plant • Serious threat to wetlands, rivers & damplands • Competes with the WA native Narrow-leaved Cumbungi & other natives • Spread by animals, water & wind • Chokes waterways • Needs to be accurately identified before removal. The WA native is narrower and has a

paler cinnamon brown flower spike with a narrower female part. Hybrids also exist. • Native to the Eastern States Control

• Eradication is difficult because of large seed production and hard to kill root system. • Cultivation, mowing, burning and herbicides are used for control. • In areas with reliable frosts, autumn cultivations to expose rhizomes can be useful. • Cutting the stems 150 mm below the water level at flowering, in late spring, results in

rhizome decay. • Burning helps reduce the build up of dead plant material that clogs channels and reduces

subsequent growth. • In dams, lower the water level, bulldoze or burn then flood deeply.

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• When removing by hand ensure the rhizomatous root is removed. • Use herbicide products registered for aquatic situations to reduce affects on aquatic

organisms.

Environmental Weed

Caltrop

FACTS

• Declared weed • Invasive to pasturelands, wastelands & road reserves • Has a sharp spined burr which contains seeds • The burr can be transported by car tyres, shoes and the fur of animals. • Seeds can germinate after summer rain events & growth is vigorous during this time • Control is prolonged and difficult Control • Small infestations by hand pulling. • Larger infestations with a combination of mechanical and herbicide control.

Environmental Weed

Cape Broom

FACTS

• Dense evergreen shrub • Produces numerous taproots from suckers • Seeds are long-lived in the soil and come up after fire before native shrubs can

regenerate • Grows rapidly & produces fire resistant seeds • Forms dense permanent thickets • Harbours rodents • Highly in flammable • From South Africa Control

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Environmental Weed

Cape Tulip One-leaved and Two-leaved

FACTS

• Declared weed • Spread by seeds & corms • Found in pastures, woodlands & disturbed lands • Toxic to stock • Takes many years to prevent reoccurrence • Native to South Africa Control • Plants can be dug out when soils are moist. Removal should be undertaken before

flowering. • Plants can be treated with selective or non-selective herbicide at flowering. Control

normally takes several years and follow up is essential. • Cultivation to expose the corms a few weeks after spraying may improve control.

Environmental Weed

Cape Weed

FACTS

• Annual daisy • Common weed of pastures, crops , roadsides and disturbed bushland. • Native to South Africa Control • Plants can be dug out before flowering is effective. • Mowing is only effective if repeated regularly and close to the ground. • Cultivation can be variable as Capeweed transplants readily in wet conditions. • Grazing is ineffective. • Plants can be treated with selective or non-selective herbicide at flowering.

Environmental Weed

Clover Narrowleaf, Hare’s Foot, Hop, Suckling, Cluster, Ball, Rose, White, Subterranean, Woolly

FACTS Mostly introduced as pasture plants

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Control • Hand pull odd plants in winter before flowering • Repeat annual herbicide spraying for several years. • Prevent seed set for 5 years • Exclude stock to prevent dispersal of seed and burrs • Clovers are relatively tolerant to grazing and mowing.

Environmental Weed

Dock

FACTS • Some seeds remain viable for 20 years. • Invades paddocks • Likes damper soils, creeks & disturbed wetlands • Prolific seeder having counted 40 000 seeds on one plant of curled dock • Seeds may germinate at any time during the growing season • Competes with crops, pastures and lawns for light moisture & nutrients. • Some animals have suffered stomach ailments and dermatitis after grazing docks heavily • Five species • Mature dock has deep root stock • Perennial herbs with erect flowering stems up to 1.25 m tall and large leaves at the base. • Native of Europe, Africa & Asia. Control • Seedlings and small infestations can be dug out. Seed head should be removed. Continual

cutting eventually kill dock. Where plants can not be treated immediately, removing fruit before it ripens in summer-autumn can prevent spread.

• Plants can be sprayed with non-selective or selective herbicides. Broadleaf selective herbicides are better and application at late spring-early summer i.e. before fruit forms is the best. Treatment usually has to be repeated over 2-4 years.

• Dock Moth • Grazing by goats although grazing and mowing can lead to greater stands.

Environmental Weed

Doublegee

FACTS • Declared pest plant • Agricultural & wasteland weed • Three rigid spines well adapted to sticking to anything • Introduced from South Africa as a salad vegetable & unintentionally in hay • Flowers in spring • Produces seed very quickly.

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Control • Remove small populations by hand and destroy plants with seeds. Older plants tend to break

off and regrow. • Spray in winter and spring with herbicide.

Environmental Weed

Evening Primrose

FACTS

• Common invader of roadside verges • Likes disturbed sites • Night flowering • Moth pollinated • From South America Control • Seedlings and small plants can be hand-pulled or dug out. All roots and any layering stems

must be removed as the plant will regrow from these. Use a weed fork and ensure all fleshy rootstock is collected and burnt or buried more than one metre deep.

• Plants can be treated using the cut-paint method before flowering commences. • Plants can be sprayed with non-selective and selective herbicides.

Environmental Weed

Flatweed (Dandelion)

FACTS Flower much of the year Control • Remove small populations by hand using a weed fork to extract the taproot. • Cultivation provides good control but leaves the area susceptible to reinvasion. • Mowing and grazing are ineffective.

Environmental Weed

Freesia, Babiana, Ixia

FACTS

• Popular garden bulbs. Freesia is a horticultural hybrid, originally from South Africa • Seriously invading bushland, granite outcrops and woodlands • Still sold in nurseries

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• Difficult to eradicate • Leaves 8-30 cm long, 5-10 mm wide, linear, flat, tapering gradually, mid-veins prominent,

green both sides, arranged as a fan. • Flowers 2-4 cm long, 6 petals, white to cream with yellow markings, trumpet -shaped,

strongly scented, flowers Sept-Oct. Control • Plants can be dug out. Remove when soils are moist otherwise corms may dislodge. When

digging, carefully excavate around the plant ensuring all corms are moved. • Grazing and mowing provide control but don’t do this after seed or cormal formation as this

may increase spread. • If plants have already developed seeds and leaf bulbils then carefully cut and bag these

before digging out of the corms. • Plants can be treated with non-selective and selective herbicides. Treat before new corms

develop and flower stems lengthen in late winter-early spring. • Start control at the top of the Catchment.

Environmental Weed

Fleabane

FACTS

• Flowers in summer and autumn • Common to roadsides and disturbed bushland Control • Hand pulling is effective on loose soils but on heavier soils a weed fork is required to prevent

the plant breaking and regrowing from the base. • Mowing is not effective. • Grazing usually gives adequate control. • Plants can be treated with non-selective and selective herbicides.

Environmental Weed

Gladiolus Pink

FACTS

• Looks similar to Watsonia • Introduced to gardens • Pink flowers in spring • Found on road verges, bushland and wasteland • Usually scattered • From Africa & the Mediterranean Control

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• Plants can be dug out. Remove when soils are moist otherwise corms may dislodge. When digging, carefully excavate around the plant ensuring all corms are removed.

• Plants can be treated with non-selective and selective herbicides.

Environmental Weed

Guildford Grass Onion Grass

FACTS

• Produced from a corm • Roadside, garden and pasture weed also occurring in bushland • Native to South Africa • Flowers in late winter and spring • Pink, purple and yellow flowers Control • Manual control is difficult because the corms tend to break off unless the soil is very loose. • Very regular close mowing with a rotary mower and cultivation in summer and early autumn

to expose corms so they dry out and die provides some control but may also spread the infestation.

• Plants can be treated with non-selective and selective herbicides.

Environmental Weed

Lathyrus

FACTS

• Climbing herb with winged stem. • Stems 3-7 mm wide, light green or grey-green, angular, winged, hairless. Leaves

alternately divided into 3 florets, one leaflet modified to form a tendril. • Rampant perennial with purple, pink or white sweet pea like flowers. • Ripe seed may be ejected several metres away from parent plants. • Seeds can remain viable in the soil for several years. • Found on roadsides and woodlands • Creates a fire hazard when it dies back in summer • Native to Europe, western Mediterranean and the Azores. Control • Small infestations can be manually removed. All stems in contact with soil must be removed

and the roots dug out to ensure no regrowth occurs. • Larger vines can be treated using the stem-scrape or cut-paint method. • Plants can be sprayed with non-selective herbicides.

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Environmental Weed

Lavender

FACTS

• Garden escapee • Found on roadsides, wastelands, creeks and drainage lines • Spanish lavender is more common than English and French • It is typically establishes on disturbed, bare or lightly vegetated sites, growing on shallow

rocky ground, sandy soils and heavier clays. • Most growth occurs over winter, spring and early summer. • Plants take two to three years to reach sexual maturity. • From the Mediterranean Control • Plants are easily hand-pulled or dug out, particularly in moist soils. To prevent regrowth roots

should be removed properly. • Dense infestations can be burnt in autumn. This will open up infestations for follow up

control. • Plants can be treated with non-selective and selective herbicides. Treatments are best

applied in spring, right at the peak flowering period.

Environmental Weed

Lupin White, Narrowleaf, Blue, Yellow

FACT Common weed to roadsides, wastelands and sometimes bushland. Control • Remove small populations by hand, mowing, grazing, cultivation before flowering and

destroy plants with seeds. • Easy to remove by hand • Spray in winter with herbicide. • Grazing by native animals usually keeps them under control in healthy bushland.

Environmental Weed

Melons

FACTS

• Wild relative of the water melon (Afghan) • Bitter & unpalatable • The small prickly paddy melon is poisonous • Grows in paddocks, roadsides and disturbed water courses

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• Grows with smaller prickly paddy melon • Native of southern Africa Control Pull out, wipe and spot spray with appropriate herbicide when actively growing.

Environmental Weed

Morning Glory

FACTS

• Garden escapee • Invasions often commence in disturbed bush land margins and openings and expand as

the canopy as the canopy dies and light level increase. • Rampant climber often used to cover fences. • Smothers all vegetation. • Regrown from pieces of roots, shoots and seeds • Seed is dispersed by wind, in garden refuse and during removal. • From Europe & Asia

Control • Small infestations can be manually removed. All stems in contact with soil must be

removed and the roots dug out to ensure no regrowth occurs. • Vines can be severed at the base and left to dry out in the canopy. • Larger vines can be treated using the stem-scrape or cut-paint method. • Plants can be sprayed with non-selective herbicides. Sever any vines climbing through

indigenous vegetation at chest height, lay lower sections on the ground then apply a herbicide spray over them.

Environmental Weed

Nasturtium

FACTS

• Sold by nurseries • Garden escapee of hybrid origin • Large seeds which germinate on disturbed soils • It is frequently dumped irresponsibly • Occurs on wastelands & creek lines • From Peru and Ecuador • Flowers in spring Control

• Manually remove, ensuring the larger roots are also collected and burnt. • There is often a large germination of seedlings following removal of parent plants. • Can be controlled by light cultivation or by herbicides.

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Environmental Weed

Nightshade (Blackberry)

FACTS

• Common garden weed • Young fruit is toxic especially to stock & young children • Spread by birds • Found in wetlands, wastelands, waterways, disturbed woodlands, and crops • Usually hairy, and often prickly. • The flower is star shaped; some times a very pointed star and flowers much of the year. • The fruit is succulent berry. • There are 43 native species in Western Australia • Only germinates where soil has been bared. Control • Hand-pull small populations before flowering. • Spray seedlings with appropriate herbicide. • Encourage shrub species and litter build up to reduce infestation.

Environmental Weed

Pampas Grass

FACTS

• Pampas grasses are aggressive colonizers, particularly of disturbed, open sites. • Individual flower heads contain up to 100 000 seeds with viability exceeding 75%. • Wind may disperse seed for several kilometers. • Roots grow to a depth of 3m with a spread of up to 4 m. • Leaves long, narrow, strap-like with a roughened, adhesive surface. • Flowering stems –6 m high, upright or nodding, emerging spring summer. Inflorescence

feathery, plume-like. • Native to South America Control • Smaller plants can be dug out. To prevent regrowth ensure the rhizomes are removed. • Where plants cannot be treated immediately spread can be limited by removing emerging

flowering stems. • Backhoes and excavators can be used to lift out large plants which can then be dried out

and burnt or buried more than one metre deep. • Where there is no risk of damage to indigenous vegetation, stock can be utilized to

control spread. • Plants can be sprayed with non-selective herbicides. • Graze infested areas if possible or replant to native shrub species.

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Environmental Weed

Patterson’s Curse (Salvation Jane)

FACTS

• Declared weed • Introduced as a possible fodder species & therefore known as Salvation Jane • 700 000 hectares of it in WA • Have purple flowers but occasionally white or pink. • Prolific seeder – more than 5000 seeds per plant. A seed bank of up to 30 000 seeds per

square metre has been reported. • Seeds can remain dormant for up to five years. • Widespread on agricultural land & roadsides and is a threat to under storey species in

reserves • Produces liver-toxic alkaloids & high intake will kill grazing animals. • Competes with other pasture plants. • Reduces soil fertility • Pollen & bristles may cause allergic reactions to humans. • Spread only through movement of seeds. I.e. through hay, wind, certified seed, animals • Can grow to the exclusion of all else • Came from the Mediterranean in the 1850s • Flowers late winter and spring and can be white or purple Control • For small invasion plants can be dug out with tap root. Seed spread can be minimized by

cutting away mature, seed-laden stems. Burn if flowering or seeding • Selective and non-selective herbicide can be sprayed for extreme invasion. Application of

herbicide should at early flowering period, other wise some seeds may ripen as plants die back.

• Cultivation controls existing plants but tends to encourage new germination • Winter grazing tends to increase infestations • Crown borer, a biological control, produces damage. • Graze heavily with wethers over spring to reduce seed production.

Environmental Weed

Poplar (White & Lombardy)

FACTS

• Reproduces from suckers & cuttings • Will continue to sucker until parent plant is killed • Planted as an ornamental • Forms dense stands • Occurs on road verges, paddocks and disturbed wetlands • Native to Europe Control

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• Suckers can be controlled by cutting off plant tops repeatedly.

Environmental Weed

Radiata Pine

FACTS • Grown commercially for timber harvest • Prolific seeder into adjacent roadsides and bushland • Affects native vegetation due to its vigorous growth & acidifying affect • Little to offer most native fauna. • Winged seeds are spread by the wind • From coastal California USA Control • Seedlings and small plants are easily hand-pulled or dug out. To prevent regrowth ensure the

main root is removed. • Plants can be cut down. Stumps do not require treating with herbicide provided cuts are

made below any branches. Plants can be treated using the Drill-Fill, Frilling or Ringbarking methods.

• Infestations can be burnt. Seedlings and saplings can be destroyed with cool burns, but larger plants usually require hot fires. Follow burns up with a control program targeting seedlings and any remaining live trees.

Environmental Weed

Ryegrass Annual

FACTS

• Introduced as a pasture species in the Wheatbelt • Infestations occur after crops are sown • Invades areas of disturbed and cultivated land and roadsides • Seed dispersal is airborne • Its pollen is a major contributor to discomfort of asthma sufferers • Seed heads can be infected with a toxicity making them toxic. • From the Mediterranean, Europe, North Africa & Asia Control

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Environmental Weed

Silver Grass

FACTS • Widespread weed of cereal crops, pastures, revegetation areas and of many other

vegetation types • Native to Europe • Flower late winter to early January Control Prevent seed set for 2-3 years by mowing, cultivation, hand weeding and herbicides.

Environmental Weed

Storksbill

FACTS • Common to pasture, wasteland, roadside • Flowers winter and spring Control • Prevent seed set for 3-5 years. • Manual removal and cultivation are effective. • Spray in winter and spring with herbicide. Hormone herbicides provide good control of young

plants.

Environmental Weed

Soursob Wood Sorrel, 4 O’clock, Oxalis spp

FACTS

• Declared plant • Invades pastures, crops, gardens and roadsides • From South Africa as a garden ornamental or in contaminated soil • Can be poisonous to stock in certain quantities • Competes with crops and annual pasture plants • Grows rapidly from food reserves in the bulb & quickly outgrows and shades most other

seedlings • Propagated by bulbs and tubers • Cut sections above the parent bulb are capable of forming new plants Control

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• Occasional plants can be carefully dug out but is difficult. Never hand-pull plants as bulbils will inevitably dislodge.

• Carefully excavate around the plant to ensure every bulbil is removed. Monitor for signs of regrowth in following years.

• Plants can be sprayed with non-selective herbicides. Repeat applications over 2-5 years are commonly required.

• Mowing and grazing are ineffective.

Environmental Weed

Stinkwort

FACTS

• Can cause stock losses and cause dermatitis • From the Mediterranean • Common to pasture, roadsides and wasteland Control • Plants can be manually removed. Plants in flower must be burnt as seed will develop from the

reserves of stems left on the ground. • Heavy grazing (with old wethers) provides some control of young plants. • Cultivation of larger plants is only effective if done before flowering. • Mowing reduces seeding but only when cut close to the ground. • Plants can be treated with non-selective and selective herbicides.

Environmental Weed

Storksbills

FACTS • Pasture, wasteland and roadside weed. • Native to Europe and the Mediterranean • Flowers in winter and spring • The distinctive fruit is long and beaklike and splits into five fruitlets which, when mature,

separate and twist so that each seed is attached to a spirally-twisted corkscrew like awn. Control • Remove small populations by hand and destroy plants with seeds. Older plants tend to break

off and regrow. • Spray in winter and spring with herbicide.

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Environmental Weed

Tagasaste (Tree Lucerne)

FACTS

• Spread from farms to road reserves & occasionally enters native bushland displacing other plants

• Reproduced by seeds. • Seed is dispersed by birds, ants, slashing, machinery, in soil and garden refuse. • Used as supplementary stock fodder • Hardy & prolific seeder • Seeds may remain in soil for more than ten years • Seedlings rarely establish in dense shade • Readily forms large thickets & displaces native vegetation • Originally introduced as a hedge plant & fodder crop and has since become weedy on

road verges, sometimes invading bushland • From the Canary Islands • Flowers in winter and early spring Control • Small seedlings and smaller plants can be hand pulled or dug out. • Plants can be treated using cut-paint method. • Stands can be slashed or burnt to stimulate seed germination for follow up control. • Bulldoze trees, burn. Then spray regrowth and seedlings. • Grazing can provide control by ring barking the trees and consuming the seedlings. • Plants can be sprayed with non-selective and selective herbicides. • Replant to native plants at least 12 months after the last spray

Environmental Weed

Veldt Grass Annual Veldt Grass

FACTS • Perennial species • Can seed 5-6 times per year. • Highly opportunistic grass capable of overwhelming road verges and bushland. • Competes with natives • Seeds prolifically & is spread by wind or on the fur of animals • Prefers sandy soils • Serious fire hazard • Native to South Africa Control • Plants are easy to hand-pull, as roots are very shallow. • Flowering plants can be gathered with catcher mowers around the time of peak spring

flowering to minimise seed production. • Manual removal by slashing and grazing of infestations before seed set is important.

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• Plants can be sprayed with non-selective or grass-selective herbicides over autumn-winter before flowering stems emerge.

• Prevent seed set for 2-3 years • Graze heavily and continually

Environmental Weed

Victorian Tea Tree

FACTS • Has become a serious roadside weed and is invading bushland down south • Likes sandy & lateritic soils • Serious fire hazard • Forms dense colonies • Still sold in nurseries • From the Eastern States • Roots produce chemicals that reduce the growth of companion plants. Control • Hand-pull seedlings. Older seedlings tend to break off and regrow. • Small bushes tend to regrow when cut but older bushes tend to die. • Grazing will control seedlings. • Spot spray small plants • Bulldoze thickets, then burn when dry.

Environmental Weed

Watsonia

FACTS • Garden escapees • Stiff upright leaves • Very serious weed in wetter areas especially roadsides, water courses, railway lines &

open woodland. • Chokes native vegetation • Serious fire hazard • Spreads & multiplies quickly from stem bulbils and underground bulbs (corms), birds &

water • Five species in the group • Introduced as a garden flower • Still sold in some garden catalogues • From South Africa • Flowers spring and early summer.

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Control • Small infestations can be removed by hand pulling when soil moist and burn the corms and

bulbs. Thick infestations are difficult to control manually. • Seasonal bulbil formation can be prevented by slashing when the stems first emerge. • Where removal is not immediately possible spread can be limited by cutting the bulbil laden

stems away. • Grazing provides effective control. • Cultivation to 100 mm provides good control if done after the old corm is exhausted and

before new corms form or before the flower stem emerges. A follow up cultivation is usually needed.

• Mowing and slashing are usually ineffective unless repeated very regularly. • Start control at the top of the Catchment. • Eradication of an area can usually be achieved in 2-3 years.

Environmental Weed

Wattles Acacia baileyana (Cootamundra Wattle),

Acacia iteaphylla (Flinder’s Range Wattle) Acacia decurrens (Black Wattle)

Acacia elata (Mountain Cedar Wattle) Acacia longifolia (Sydney Golden Wattle)

Acacia podalyriaefolia (Queensland Silver Wattle) Acacia pycnantha (Golden Wattle)

Acacia dealbata (Silver Wattle) Acacia melanoxylon (Blackwood)

FACTS

• Eastern State’s varieties • Planted in gardens, farm windbreaks or early rehabilitation work. • Some are particularly invasive • Most species listed above, live for twenty years or longer • Popular garden and public open space plant due to its easy cultivation • At least seven species which are seriously colonizing roadsides & bushland • Prolific seeders with seed able to survive many years. • Competes with native vegetation Control • Seedlings and small plants are easily hand-pulled or dug out. To prevent regrowth ensure the

roots are removed. • Younger plants can be treated using the cut-paint or drill-fill methods. • Fire destroys plants and stimulates seed germination for herbicide treatments or manual

removal. • Seedlings will need to be controlled for several years. • Avoid burning infestations unless there are sufficient resources for follow up work. • Seedlings and small plants can be sprayed with non-selective or selective herbicides. A

follow-up treatment on emerging plants is essential. Repeat treatment every 2-3 years. • If hand pulling, ensure roots are removed with the seedling by using a weeding fork. • Don’t buy or plant these species

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Environmental Weed

Wild Oats Bearded Oat, Wild Oat, Ludo Wild Oat

FACTS • Most serious weed found in cereal crops around the world • Opportunistic grass species • Increasing problem on disturbed land • Seed dispersal is airborne • From the Mediterranean region • Most serious weed found in cereal crops around the world Control Manual removal, regular mowing, grazing or spraying particularly in spring when seeds are produced. Prevent seed set for 3-5 years

Environmental Weed

Wild Radish And Mediterranean Turnip, Turnip Weed, Hedge Mustard,

Indian Hedge Mustard, Wall Rocket, Sand Rocket (Lincoln Weed) FACTS

• Persistent roadside & paddock weed and flourish in under grazed situations. • Common horticultural & agricultural weed • Economically one of the most important weeds of cropping • Seeds viable for a long time • Flowers are white, yellow or pink to mauve • Native to Europe and Asia • Common to roadsides and disturbed areas near cultivation but not often invading bush. • Flower from Autumn to Spring • Mature and set seed quickly • Once pods are formed, seeds will often mature even if the plant has been uprooted Control

• Manual removal effective but must be done at least 8-10 weeks. • Many are unpalatable so grazing only offers partial control. • Isolated plants should be removed manually and burnt if flowering and seeding. • Plants can be sprayed with non-selective and selective herbicides.

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Environmental Weed

Willow FACTS

• Weeds of national significance • Compete vigorously for space, water and nutrients eliminating all indigenous vegetation with

an infestation. • Broadly grouped into tree or shrub forms. • Leaves variable in colour and shape. Seed minute. Roots woody. • Reproduce by seed and vegetatively. • Seed is dispersed by wind and water. Control • Seedlings and small plants can be dug out. Tops are very likely to break away when pulled so

if root remain they should be dug out. • Plant less than 10 cm in diameter can be treated using the cut-paint method. • Seedlings, saplings and regrowth from failed cut-paint treatments, can be sprayed with non-

selective herbicides. Follow up treatments may be required as plants sometimes re-shoot.