Leschenault Biosecurity Group

MyWeedWatcher App

The Department of Agriculture and Food WA have developed a smartphone and tablet App to assist the community to identify, survey and report weeds, and to view the results online.

The free App can be downloaded by clicking on the image below.


Pest Identification

Apple of Sodom

Native of South Africa and the Mediterranean area. In Western Australia it has mainly been found on coastal limestone soils from Yanchep to Mandurah and around Busselton and Augusta. It is also occasionally seen further inland.

Apple of Sodom is an erect branching woody shrub. It usually grows about 1-2m high, but occasionally reaches 5m. The plant forms dense thickets which provide cover for rabbits and shade out pasture plants. The thickets also restrict the movement of farm animals and machinery.

  • Stems: green-purple to brown with 1cm long curved straw coloured spines.

  • Leaves: long leaves with deep irregular lobes. They are up to 15cm long with long curved spines on both surfaces of the leaf. These are arranged along the veins and leaf stalk. Both stems and leaves are covered with minute star-shaped hairs.

  • Flowers: appear in spring and summer. They are about 2cm across and their colour is purple-white with a yellow centre. Flowers contain five petals joined to form a star and curved inwards like a bell.

  • Fruits: round, tomato-like fruit, green and white at first, turning yellow, then brown and black as it ripens. The fruit is about 30mm in diameter. It contains numerous round flattened light brown seeds each about 3mm across.

  • Seeds: most of the seed germinates in spring and late summer. Some seed may remain dormant in the soil for several years. Germination is greatly increased when the adult plant is removed.

Arum Lily

Arum lily is a robust, dark green, succulent herb, also known as calla or white arum lily. It was introduced to Western Australia from South Africa as a garden plant and subsequently escaped to become established as a weed. It is found in creeks, irrigation ditches and areas of summer-moist land in the higher rainfall south west of WA, often forming large dense clumps.

It competes with valuable perennial pasture plants on summer land. It has been claimed to cause eczema in humans. Stock deaths have occurred from grazing arum lily.

Arum lily has fleshy roots and forms extensive tubers which store food for future use. The roots when boiled provide a starchy food for some South African tribes, however, they are poisonous when eaten raw. Arum lily spreads vegetatively by regeneration from tuber fragments and by seeds.

  • Leaves: the petioles (leaf stalks) are up to 0.4m long and smooth; the leaf blades are thick and fleshy, pointed at the apex with blunt lobes at the base.

  • Flowers: white to greenish white and tubular flowers, becoming funnel shaped at the top with a slit down one side. Flowering takes place in spring.

  • Fruit: the berry is oval, yellowish, about 1cm in diameter and contains several round seeds about 3mm in diameter.


Semi-deciduous scramblers to 2m high with canes up to 7m long. Native to Europe and adjacent areas. Spread by seed, rooting of cane tips, and by suckers from lateral roots. The latter two means of spread result in large clumps over time. Fruit is eaten by birds and mammals (especially foxes) that may transport seeds some distance. Blackberry is a Weed of National Significance.

  • Stems: mostly arching, green, reddish or purple, ribbed lengthwise, with or without hairs. Plant covered with numerous prickles straight or curved, 3-12mm long.

  • Leaves: usually comprise three or five leaflets with toothed margins, dark green on the upper surface and with many to no hairs underneath.

  • Flowers: to 3cm wide with five white or pink petals. Flowers late spring to summer.

  • Fruit: globe-shaped, 1-3cm across, initially green ripening through red to black, composed of numerous small juicy segments.

  • Seeds: pitted to 3mm long.

Cape Tulip (one-leaf)

One-leaf Cape Tulip (Moraea flaccida) is a native of South Africa. Perennial herb to 70 centimetres high, distinguished by fibrous-sheathed corm at the base of the plant, orange to salmon pink flowers that are yellow in the centre; single leaves and presence of seeds in capsules. Corms one to four centimetres wide, developing new corms each year. Spread by seed and movement of corms. Often found in hay cut from infested paddocks.

Originally introduced as a garden plant in the 19th century. Seeds germinate in autumn and plants regrow from corms at the same time. Poisonous to stock but generally avoided by them. Young stock may be affected if there is no alternative grazing available. One –leaf Cape tulip is a serious pasture weed in Western Australia, South Australia and Victoria.

  • Leaves: leaf folded. Ribbed, linear, to one metre long, extended and drooping above the flowers.

  • Flowers: borne on branched stems, orange to salmon-pink, occasionally yellow. Flowers with six petals, each 2-4 cm long, not joined to each other. Flowers in spring when two or three years old.

  • Seeds: angular red brown seeds, about 2mm long, in narrow-cylindrical capsules 2-5cm long, splitting from the apex into three parts.

Cape Tulip (two leaf)

Two leaf Cape Tulip (Moraea miniata) is a perennial herb to 60cm high, native to South Africa. It can be confused with one-leaf Cape tulip (Moreae flaccida), which produces seeds and has a single basal leaf. The two species can be distinguished by the covering (tunic) around the corm at the base of the plant.


  • Leaves: two or three leaves, folded, ribbed, linear, to 80cm long.

  • Flowers: pink-salmon coloured flowers with a green dotted yellow centre on branched stems. Flowers with six petals, segments 1-3cm long, not joined together. Flowers late winter and spring when two or three years old. Does not produce seeds, but does form a capsule to 1.5cm long, which splits from the tips into three parts.

  • Corms: corms 1-2.5cm wide, developing new corms each year. Plants produce clusters of cormils in the swollen leaf axils and many small corms (cormils) around the parent corm. Grows from corms and cormils in autumn. The corm and cormils have a hard black covering (tunic).

Narrow-leaf Cottonbush

An erect slender shrub 1-2m high with narrow, opposite leaves, and bladder-like fruit. All parts of the plant exude a milky white sap when damaged. It reproduces by seed and suckers.

  • Stems: pale green, 60-180cm covered with short whitish downy hairs when young.

  • Leaves: dull green, occasionally with shiny upper surface. They are 5-12cm long, 6-18mm wide, tapering to a point and are opposite each other in pairs.

  • Flowers: white or creamy with five fringed waxy lobes turned sharply outwards. They are formed in a loose drooping cluster of three to ten flowers in the leaf axils.

  • Fruit: distinctive seed pods that are puffy, swan-shaped structures up to 6cm long and 2.5cm wide and covered in soft spines up to 1cm long.

  • Seeds: contained within a thin walled sack that is separated from the outer wall by an air space. Brown coloured, flattened and egg shaped about 6mm long and 3mm wide with a tuft of silky hairs about 3cm long at one end.


Hairless annual, usually prostrate but can grow taller among other plants. Native of South Africa.

  • Stems: mostly prostrate, to 50cm long, several arising from the crown, hairless, ribbed, fleshy and purple at the base and nodes.

  • Leaves: triangular to oval, hairless, each leaf stalk surrounded by membranous sheath at the base.

  • Flowers: male and female flowers are separate and inconspicuous. The male flowers are in clusters on small stalks, while the female flowers are almost without a stalk and form in the leaf axils.

  • Fruit: woody and hard, 7-11mm long and triangular in longitudinal cross section, each angle extending to rigid sharp spine. There are four pits on each face. Changes from green to brown when mature.

  • Seed: triangular and one per fruit.

Paterson’s Curse

An erect annual (occasionally biennial) herb to 1.5m high, commonly 30-60cm, reproducing by seed. Native to southern Europe. Widespread throughout the south-west of WA, and the eastern Goldfields.

  • Stems: one to several stems arise from base, much branched and covered with stiff white hairs.

  • Leaves: alternate, bristly. Rosette leaves to 25cm long, oval to oblong, stalked and with distinct lateral veins. Stem leaves are smaller and narrower, not stalked and almost clasping the stem.

  • Flowers: purple, rarely pink or white, crowded along one side of a curved spike. Five petals joined in a curved trumpet shape, 2-3cm long. Five stamens, two of which are longer than the others and extended beyond the petals.

  • Fruit: a group of four nylets surrounded by a stiffly bristled calyx.

  • Seeds: brown to grey, 2-3mm long, three sided strongly wrinkled and pitted.

Variegated Thistle

Variegated thistle is native to southern Europe and the Mediterranean. It was probably introduced as a medicinal plant or a contaminant of grain before its weed potential in WA was recognised. In WA it has become an important weed of the high and medium rainfall districts of the south west of the state. When established it competes with more useful pasture plants for light, moisture and nutrients.

Under certain conditions, variegated thistle is poisonous. It can kill cattle and occasionally sheep, especially when hungry animals consume large quantities in the absence of alternative feed. It becomes more palatable to stock – and more toxic – when it has wilted after cutting. It has numerous spines which may cause injury to animals, including domestic dogs. Variegated thistle is also an important contaminant of wool and the plant provides excellent cover for rabbits.

Variegated thistle is usually an annual plant but occasionally does not flower until the second year. A large plant may cover an area of one metre in diameter. It reproduces only from seed.

  • Leaves: Variegated thistle forms a broad rosette of shiny dark green leaves variegated by a network of white veins and patches. The leaves are deeply lobed with a long spine at the point of each lobe.

  • Flowers: in spring a branched flowering stem, without prickles, grows up to 2m high. Flowering starts in October and continues until early summer. One large purple flower head is produced at the end of each branch. Each head is enclosed by numerous overlapping bracts, each bract having a large stiff spine at the tip and shorter spines along the edge.

  • Seeds: The seeds are black or brown, about 5mm long, somewhat flattened with a smooth seed coat. They are equipped with a parachute-like pappus of pale, barbed hairs about 2cm long. Seed set takes place in summer. The seeds are too heavy to be blown far by wind in spite of the pappus, therefore most seeds fall onto the bare ground near the base of the parent plant. Variegated thistle seed may remain dormant in the soil for up to nine years. As little as 50% of the surviving seed may germinate in any one year.