weed identification

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Weed identification

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Weed identification

Bindweed Description:

Summer growing, deep rooted perennial with creeping roots. Slender twining stems with runners up to 1m long. Arrow shaped leaves on slender stalks rising from runners. Flowers are pink or white, trumpet-like.

Problem Competes for moisture and

nutrients in crops pastures and gardens.

Grows rapidly over cereal crops making harvest difficult.

Caltrop Description:

A prostrate, hairy summer annual. The stems are thin, wiry, up to 1 metre long from a central taproot. The leaves are in opposite pairs, divided into 4-7 pairs of leaflets. Flowers have 5 yellow petals. The fruit is a cluster of 5 burrs, straw coloured when ripe. Each burr is wedge shaped, 6-9mm long with 2 long sharp spines and 2 shorter ones.

Problem:- Burrs injure feet of humans and stock, cause internal injuries if swallowed, damage tyres, contribute to vegetable fault in wool.- Spreads readily in urban and horticultural situations. - Unpalatable. If grazed by sheep can cause nitrite poisoning and photo-sensitisation.

Mintweed Description

an annual grey, green herb with 4-sided stems. Leaves narrow oblong with blunt tip. Produces a strong minty odour when crushed. Flowers pale blue, tubular, in opposite pairs or groups of 3 or 4.

Problems- a weed of roadsides, crops and pastures- caused nitrate poisoning in sheep and cattle

Pigweed Description

a succulent prostrate annual with stems often reddish brown. Leaves shiny, oblong to wedge shaped 1-2 cm long. Flowers in leaf axis, yellow, solitary or clustered.

Problem- common weed of cultivation in high rainfall areas- Suspected of causing nitrate and oxalate poisoning

Bathurst Burr Description:

An erect, summer growing annual. The stems are branched and straw coloured. It has leaves that are dark green with white or pale green veins; three lance-like lobes with the centre lobe longer. The flowers are minute and in the joint of the stem and leaves. The burrs are ovoid, about 1cm long, covered with hooked prickles; contains two seeds (one may be dormant for years). Stems have many groups of 3-pronged, stiff yellowish spines at base of each leaf or branch

Problem:- Burrs contaminate wool.- Spines are obnoxious.

Bathurst Burr

Noogoora Burr

Noogoora Burr Description:

Summer annuals to 2 metres in height.Leaves grape-vine like, hairy on both sides. Deep tap root. Stems - dark flecks/spots.Flowers - inconspicuous, near stem tipsBurrs - 2 to 3cm long, covered by hooked spines, beaked

Problem:- Seedlings poisonous.

- Burrs irritate stock, downgrade wool.

- Burrs spread by stock, produce, machinery.

-  Burrs invade riverbanks, swamps, flooded areas.

-  Noogoora burr capable of spreading in dry areas.

Galvanised Burr Description:

One of the native copperburrs or bassias, forming a densely branched shrub to 1m high. Stems numerous wiry, tangled, densely wooly with fine white hairs. Leaves oval, blunt, greyish, woolly with fine hairs. Burrs woolly, persistent along the branches, each bearing three spines 8 to 15mm long and two very short spines.

Problem:- Unpalatable to sheep.

- Burrs can cause vegetable fault in wool.

- Reduces the value of pastures.

Variegated thistle Description:

Annual plant 1-4m high. Leaves shiny, large, deeply cut, light to dark green. White vein network gives variegated appearance. Tipped with strong spines. Flowers large, purple, to 120mm diameter. Seeds numerous, with large pappus (parachute)

Problem- Smothers pastures.- Can be poisonous to livestock.

Variegated thistle

Sowthistle Description

an erect annual herb with hollow stems, exuding latex if damaged. Thin, soft dark green leaves with irregularly-toothed margins, ending in small soft spines. Flower heads yellow.

Problemswidespread throughout Australia

Sowthistle

Prickly Pear Description:

A succulent perennial up to 7 metres. The stems are fleshy, jointed into pads, generally flat, some cylindrical. (Stems contain chlorophyll and act as leaves.) The leaves are mostly reduced to spines surrounded by fine hairs in clumps on the pad surface. It has large, brightly coloured flowers on the pad margins. The fruit is usually fleshy, edible, ruby red to yellow.

Problem:- Propagates by seed or pads in contact

with the ground.- Survives and spreads under arid

conditions.- Obnoxious spines.- Forms dense thickets to the exclusion

of livestock and desirable species.- When eaten by livestock, fine bristles

may cause severe irritations in the animal's mouth.

Mother-of-millions Description

A smooth, succulent, erect perennial herb with pinkish to grey stems. Leaves almost cylindrical with purple markings and a slight groove in the upper surface. Flowers yellow to salmon red, occurring in clusters at end of stems.

ProblemIts toxic and has caused

cattle deaths. Apparently toxic to

humans

Blackberry Description:

Scrambling, thorny perennial bushes. Compound leaves of 3-5 oval leaflets. Sharp, curved spines on lower surface veins. Flowers white/pink with 5 petals. Fruit is black. Spread by suckers, layered stems and seeds

Problem:- Invades agricultural land

and native vegetation.- Hinders access.- Harbours vermin.

St Johns Wort

St Johns Wort Description

a hairless, rhizomatous perennial herb or small shrub. Leaves have oil glands which appear to be preformations when held up to the light. Stems reddish bearing near the top yellow flowers with 5 petals.

ProblemsWeed of pastures. It can cause photosensitisation in stock as well as nervous disorders and, in humans, contact dermatitis.

Nutgrass Description

a perennial sedge with unjointed stems triangular in cross-section. Bright green leaves emerge at ground level, tapering to a point. Underground purple, spherical tubers are found on rhizomes. ‘Nuts’ give rise to new shoots and new rhizomes.

Problem- weed in more than 90

countries- Weed of cultivation,

vineyards, lawns, orchards and market gardens

Nutgrass

Serrated tussock

Description:a densely-tussocky perennial grass. Leaves tighly rolled, rough to touch. In winter the species has a characteristic yellow colour.

Problem:Has no grazing value to sheep

and is a major problem of grazing land

Salvinia

Salvinia Description:

Free floating aquatic fern. Leaves are oval. As the leaves multiply they become closely folded, giving the plant a characteristic appearance. Upper surface of leaves covered with white waxy hairs. Has no true roots. Fine leaves that look like roots hang into the water and absorb nutrients.

Problem:- Capable of reproducing

very quickly.- Blocks lakes, dams, drains

and irrigation channels.- Decaying debris pollutes

water.

Patterson’s Curse Description

Annual herb. Hairy, dark green, broadly oval rosette leaves to 30cm long; the several seeding stems grow to 120cm in height and develop branches with age. Flowers develop in clusters; they are purple, tubular, and 2-3 cm long with 5 petals. It has a fleshy taproot with smaller laterals.

Patterson’s Curse

Thornapple or castor oil Description: Annual to perennial herb to

1 m high and 2 m wide. Leaves ovate and 6–20 cm long. Capsule globe-shaped, 3–5 cm long.

Distinguishing features: Distinguished by dense, erect glandular hairs on stems; flowers white with green veins, 12–19 cm long, stigma well above anthers; capsule with numerous slender spines, all nearly the same length (to 1 cm long), capsule stalk bent sharply downwards; seeds brown, 4–5 mm long.

Notes: Widely distributed weed of disturbed land. A weed of summer crops. All parts of the plant, particularly seeds, are toxic to livestock and humans. Rank smell and bitter taste usually deters stock from grazing plants.

Bladder Ketmia Wide leaf bladder ketmia is

an erect annual plant, five to 150 cm tall with waxy, green leaves that are around 90 to 100 mm long and 70 to 80 mm wide. There are two types of wide leaf bladder ketmia. Both have cream or yellow petalled hibiscus-like flowers, but are differentiated by the colour found at the centre of the flower.

One type of wide leaf bladder ketmia has flowers with a yellow centre The other type of wide leaf bladder ketmia has flowers with crimson/red centres

Cobblers Pegs or farmers friend

Cobblers Pegs or farmers friend

Description: Native to Europe,

Cobblers Peg is a herb up to 2m high. Mainly seen shorter in coastal areas. Found in disturbed areas exposed to full sun..

Yellow sometimes white flowers, flowering all year.

Black seeds 1cm long with forked tip.

Khaki weed Description:

A prostrate, creeping herb. The stems are branched, reddish purple, and covered with short soft hairs. The tap root is enlarged and perennial. It has green leaves up to 5 cm long, oval shaped, pointed tips, in unequal opposite pairs. The flowers are in axils of leaves and are surrounded by fine sharply pointed burrs. The burrs are straw-coloured and prickly.

Problem:- Suspected poisoning in sheep

and pigs, skin ailments in cattle.- Obnoxious burrs in horticultural

and urban areas over summer.- Burrs infest wool, fodder.- Plants spread by creeping stems.- Seed prolific and viable for years.

Parthenium weed Description:

An annual herb with a deep tap root and an erect stem, which becomes woody with age. Leaves are deeply lobed, alternate, pale green, covered with soft fine hair. Flowers are creamy white.

Problem:- Can establish in over-grazed

pastures.- Can cause dermatitis to man.- Direct contact between skin

and plant should be avoided.- Allergic skin reactions in

livestock have been reported.