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weed with sticky seeds australia

Broadleaf Weeds

General Description: Bindii is a low growing weed with carrot-top like leaves, it produces a single flower at its centre, that when matures produces a prickly seed pod. The bindii prickles become easily stuck in feet.

Key Distinguishing Feature: Burr in late winter spring, Carrot top like leaves.

Key Products for Control: Bow & Arrow – 50mL/100m2

Capeweed

Common Names: Capeweed

Botanical Name: Arctotheca calendula

Family: Asteraceae

Lifecycle: Annual
Seasons of Growth: Autumn / Winter

General Description: Capeweed starts appearing from February to about April. It
forms a rosette of grey-green succulent leaves and has yellow daisy like
flowers with black centres in spring and early summer. Capeweed is similar to
many other rosette type of weeds, the key difference being the leaves have
white and quite hairy undersides.

Key Distinguishing Feature: Large bright yellow flowers with brown centre. White &
hairy undersides.

Key Products for Control: Bow & Arrow – 50mL/100m2

Cats Ear, Flatweed

Botanical Name: Hypochoeris radicata

Family: Asteraceae
Lifecycle: Perennial
Seasons of Growth: Year round

General Description: Cats Ear is a herb to 400 mm wide with yellow daisy type flowers up to 30 mm diameter borne on simple or branched, leafless stalks at any time of the year with a flush in spring to early summer. The small florets all have radiating petal-like blades. The tiny fly-away fruits are topped by a stalked ring of barbed to feathery bristles. The leaves form a flat rosette and are variable being entire to shallowly lobed, and usually somewhat bristly but can be hairless. The flower stems often have galls. It is a perennial but often acts as an annual in drier climates.

Key Distinguishing Feature: Yellow daisy like flowers.

Key Products for Control: Bow & Arrow 50mL/100m2

Chickweed

Botanical Name: Stellaria media

Family: Caryophyllaceae Lifecycle: Annual
Seasons of Growth: Winter / Spring

General Description: Chickweed is a common weed throughout Australia, as well as the world. It is a small plant with shiny leaves on multiple stems which produce a single white flower on each stem. While it is an Annual, it can mature and start re-seeding a new generation of weeds in around 6 weeks.

Key Distinguishing Feature: White flowers, shiny leaves.

Key Products for Control: Contra M – 65mL/100m2

Clover, White Clover

Botanical Name: Trifolium repens

Family: Fabaceae (Legume) Lifecycle: Perennial
Seasons of Growth: Autumn / Winter

General Description: Clover has leaves with three leaflets, and creeping stems that set roots at whatever point they touch the ground. Flowers are white or pink. Clover, with white flowers, is a member of the pea family. This means clovers can fix nitrogen from the air and therefore they favour poorly fertilised lawns.

Key Distinguishing Feature: 3 Leafed Foliage, White / Pink flowers.

Key Products for Control: Bow & Arrow – 50mL/100m2

Cotula (Carrot Weed, Funnel Weed)

Botanical Name: Cotula australis

Family: Asteraceae
Lifecycle: Annual / Perennial Seasons of Growth: Autumn / Spring

General Description: Cotula australis is a species of plant in the daisy family. Cotula grows low to the ground in a thin mat with some slightly erect, spindly stems. The leaves are finely divided. The plant flowers are only a few millimetres wide containing minuscule yellow florets surrounded by greenish brown bracts.

Key Distinguishing Feature: Finely divided leaves, Greenish coloured flowers.

Key Products for Control: Contra M – 65mL/100m2

Creeping Oxalis, Yellow Wood Sorrel

Botanical Name: Oxalis corniculata

Family: Oxalidaceae
Lifecycle: Perennial

Seasons of Growth: Spring / Summer / Autumn

General Description: Creeping oxalis is a small weed which grows from stolons and is
typically found in lawns. It doesn’t have underground bulbils, though the
stolon system is still an efficient form of vegetative reproduction for this
species. It allows creeping oxalis to spread out through turf to form quite
dense mats at times. It is helped by its tolerance of many of the commonly used
selective turf herbicides. It has little yellow flowers which help make the
plant obvious at those times of the year when it is flowering.

Key Distinguishing Feature: Small Yellow flowers.

Key Products for Control: Bow & Arrow 50mL/100m2

Cudweed

Botanical Name: Gnaphalium spp.
Family: Asteraceae
Lifecycle: Annual / Biennial Seasons of Growth: Spring / Summer
/ Autumn
General Description: Cudweed is an annual or biennial weed with a rosette forming
growth habit. The leaves are broad and obovate in shape and possess a dull
green upper surface with a soft, white or silver hairy underside. Growth begins
as basal rosette forming stems with upward growth occurring as the plant
matures. Cudweed flowers typically form from spring throughout summer and are
purple to pink in colour.

Key Distinguishing Feature: Silver undersides of the leaves. Rosette habit, silver/white
underside leaf.

Key Products for Control: Bow & Arrow 50mL/100m2

Dandelion

Botanical Name: Taraxacum officinalis

Family: Asteraceae
Lifecycle: Perennial

Seasons of Growth: Spring / Summer

General Description: A rosette forming, biennial or perennial plant with backward pointing lobes on its leaves and single bright yellow flowers on long stalks and milky sap. Seeds germinate in autumn and to a lesser extent in spring.

Key Distinguishing Feature: Bright yellow flowers and milky sap.

Key Products for Control: Contra M – 65mL/100m2

Fleabane

Botanical Name: Conyza spp.

Family: Asteraceae

Lifecycle: Annual / Perennial

Seasons of Growth: Year round

General Description: A short-lived herbaceous plant developing a basal rosette of leaves at first. Its upright branched stems are densely hairy and usually grow up to 1 m tall. Its lower leaves (4-10 cm long) are elongated in shape with bluntly toothed to deeply lobed margins. Its small flower-heads (6-12 mm across) do not have any obvious ‘petals’ and turn whitish and fluffy as they mature.

Key Distinguishing Feature: Fluffy white flowers, basal rosette of leaves.

Key Products for Control: Contra M – 65mL/100m2

Khaki Weed

Botanical Name: Alternanthera pungens

Family: Amaranthaceae Lifecycle: Annual stems, perennial rootstock.

Seasons of Growth: Spring / Summer / Autumn.

General Description: A dense mat forming plant with annual tops, a fleshy, perennial rootstock, reddish, hairy stems and prickly burrs. Seeds germinate in spring and summer after rain and produce creeping stems and a stout rootstock over summer. Stems take root at the nodes forming a dense mat. Flowering occurs from March to April and the top growth dies in winter. New shoots emerge from the rootstock in spring.

Key Distinguishing Feature: Prickly Burrs. Reddish hairy stems. Fleshy Taproot.

Key Products for Control: Contra M – 65mL/100m2

Lambs Tongue, Plantain, Ribwort

Botanical Name: Plantago lanceolata

Family: Plantaginaceae — Lifecycle: Perennial
Seasons of Growth: Autumn / Winter

General Description: Plantain has hairy, long, slender ribbed leaves that form 1 or more rosettes from which emerge long, slender flowering stems carrying dense, brown, cylindrical seed heads that often have white anthers sticking out of them from October to March or in July.

Key Distinguishing Feature: Long Slender, hairy ribbed leaves.

Key Products for Control: Contra M – 65mL/100m2

Marshmallow, Mallow

Botanical Name: Malva parviflora

Family: Malvaceae
Lifecycle: Annual or biennial. Seasons of Growth: Spring / Summer / Autumn

General Description: Marshmallow is an exotic annual weed that is dynamic after autumn and winter rains. It is an erect, sprawling or decumbent herb growing up to 50cm high that is covered with rather stiff star-like hairs and is woody at the base. Primarily occurs in southern Australia. Germinates in spring to autumn and grows rapidly. Flowers August-December. Spring germinating plants may flower when only a few centimetres high and survive over summer to become biennial.

Key Products for Control: Contra M – 65mL/100m2

Medic, Burr Medic, Black Medic

Botanical Name: Medicago polymorpha

Family: Fabaceae

Lifecycle: Annual

Seasons of Growth: Autumn / Winter / Early Spring

General Description: Burr Medic is a low-growing, almost hairless, sprawling herb with leaves divided into 3 heart-shaped leaflets each 4-25 mm long. The terminal leaflet is on a longer stalk than the two side leaflets. It has clusters of 2-7, small, yellow, pea-type flowers with petals that are only 3-5 mm long. The fruit is a small, greenish-brown burr with 1-6 tight coils that are often spiny. Native to the Mediterranean region, Burr Medic is a common weed of gardens, pastures and roadsides and flowers in winter and spring.

Key Distinguishing Feature: Yellow flowers, black marks on centre of leaves.

Key Products for Control: Contra M – 65mL/100m2

Pearlwort

Botanical Name: Sagina procumbens

Family: Caryophyllaceae Lifecycle: Perennial
Seasons of Growth: Spring / Summer / Autumn

General Description: Pearlwort is a dense low growing dicot weed with smooth slender stems rooting at the nodes with oppositely arranged, thin grassy like leaves up to 14mm long. The heavily branched stems form a mat-like growth habit that forms thick ground cover. Small flowers appear in spring, summer and autumn and are a small, inconspicuous flower with green sepals and tiny white petals. Flowers remain closed in bud and bloom briefly. Pearlwort is propagated mainly through seed but can also grow from vegetative parts.

Key Distinguishing Feature: Tiny white flowers.

Key Products for Control: Contra M – 65mL/100m2

Pennywort, Pennyweed

Botanical Name: Hydrocotyle tripartita

Family: Apiaceae
Lifecycle: Perennial

Seasons of Growth: Late Winter / Spring

General Description: A small long-lived herbaceous plant with creeping stems. Its slender stems are hairy and take root at the joints. Its small leaves (1.2-3 cm across) are borne on stalks 1-10 cm long and have three to seven toothed lobes. Its tiny flowers are densely arranged in small clusters that are borne on stalks about 1.5 cm long its small rounded fruit are about 1 mm across and split in two when mature.

Key Distinguishing Feature: Small leaves and creeping stems.

Key Products for Control: Contra M – 65mL/100m2

Thistles, Sow Thistle

Botanical Name: Sochus spp

Family: Asteraceae
Lifecycle: Annual
Seasons of Growth: Autumn / Spring

General Description: An erect, hairless, branched plant with sprays of yellow, thistle type flowers at the ends of branches and large, soft, lobed leaves. Common Sowthistle is an erect, hairless, annual or biennial herb about 1 m tall with hollow stems which have a milky sap. Basal leaves are up to 30 cm long, form a rosette and are soft and lobed or toothed. The yellow flower heads are clustered, each about 2 cm in diameter. The tiny fruits are short and flattened. It flowers for much of the year but mainly in spring and early summer.

Key Distinguishing Feature: Yellow flowers that flower most of the year.

How to Control Sticky Weed

If you have this in the garden you will know why it is called ‘Sticky weed’. The whole plant becomes sticky and it attaches itself to other plants, fences and just about anything else. Even as you touch it it likes to attach itself to your skin or gloves. It will smother other plants if left and will spread all over the yard in time..

It mainly spreads from seed, however the flowers themselves are fairly small and you may not notice them. As it is an annual you can control it with a little effort over a few years.

Tar vine

Please note: This content may be out of date and is currently under review.

Tar vine (Boerhavia coccinea) is found throughout Australia, with the exception of Tasmania. It is a common summer weed species, and like most summer weeds it depletes soil moisture and nutrients, reducing the yield potential of the subsequent crop. Tar vine also acts as a green bridge for crop pests and disease. It can be a beneficial and highly palatable pasture species. However, tar vine has sticky seeds, which may contaminate wool. This weed is difficult to control, as the stressed, dusty plants are poorly responsive to herbicides.

Tar vine seedling.JPG

Mature tar vine plant at Mullewa.JPG

Tar vine flower.JPG

Tar vine at Wongan Hills.JPG

Tar vine seeds.JPG

Identification and attributes

Tar vine is also known as tah vine, scarlet spiderling, common spiderling, giotcho, red Boerhavia or hogweed. It is an annual or perennial species, which usually grows as a summer weed in Australia.

Tar vine is a low-lying, sprawling plant with stems that can exceed a meter in length. The plants can be 2m across and 1m high, but are usually prostrate and about 10cm high (growing as a vine). Stems may be prostrate or bend upwards near the end. The stems are usually densely branched, hairy and covered in glands that make the plant sticky. As a result, it is common to have sand grains sticking to the leaves, stems and seeds. The leaves are oval-shaped (ranging from egg-shaped to lance-shaped), held on short stems. They can be wavy along the edges and may have reddish margins. The leaves are in opposite pairs, one smaller than the other. The inflorescence may have three or many tiny, frilly flowers, each just a few millimetres long. The flowers can be white, pink, red, purple or yellow. The non-fleshy fruits are pear shaped and about 3mm long. Each fruit contains one seed. The plants develop a stout taproot with a well-developed root system.

Biology

The optimal temperature for germination is 25°C. Tar vine is generally considered a spring/summer plant, but germination may occur throughout the year, depending on location.

Tar vine seed has initial dormancy. Seed buried at a depth of 2cm have initial germination of about 10%, and seeds on the soil surface have an initial germination of 1%. Following removal of dormancy, about 70% of the seed germinate. An experiment at Merredin and Northam, Western Australia, demonstrated that tar vine seed germination is highly variable. Seed from the same population was placed on the soil surface in November 2014, after it was harvested from tar vine that matured in the spring of 2014. In Merredin, low levels of germination occurred over a period of 1.5 years, in different seasons. In Northam, all germination occurred in the spring of the following year. Therefore, seed may remain dormant for over a year, or germinate in the year following seed production, depending on environmental conditions. Germination may have been more rapid in this experiment if the seed was buried.

Following germination, the plants can grow as annuals or perennials. If plants germinate after summer rainfall and run out of moisture, they can produce flowers and set seed 2-3 weeks after emergence. If sufficient moisture is available, plants grow vigorously over spring and summer, but die back to the base in response to cold autumn/winter conditions.

Tar vine grows in a wide variety of habitats, and is found in tropical, subtropical, semi-arid and temperature regions of Australia. However, it is most prolific in disturbed sites. This species disperses via seed movement. As the seeds are frequently sticky, they can attach to livestock or clothing and machinery.

Why is it a weed?

The origin of this species is unknown, but it may be native to the Kimberley, Pilbara and desert regions of Western Australia. There are twelve species of Boerhavia in Australia, but B. coccinea is the most common in disturbed areas like agricultural fields or roadsides. It is a common summer weed species and like most summer weeds it depletes soil moisture and nutrients, reducing the yield potential of the subsequent crop. This weed also acts as a green bridge for crop pests and disease, including scab disease, melon viruses, Xylella fastidiosa disease of grapes and plague locusts. It can be a beneficial and highly palatable pasture species. Some species of Boerhavia are consumed by people, but B. coccinea should not be harvested for human consumption. Leave it for the stock to eat. While tar vine contains oxalates, the levels are unlikely to be high enough to be toxic to livestock. However, livestock should be removed if toxicity is suspected. Tar vine has sticky seeds, which may contaminate wool. This weed is difficult to control, as the stressed, dusty plants are poorly responsive to herbicides.

Herbicide resistance

Tar vine is not herbicide resistant, but glyphosate is commonly overused for management over the summer fallow, so resistance may develop.

Tactics for integrated weed management

Knockdown control

Tar vine is difficult to control over summer. A single application of non-selective herbicide is ineffective when used against mature, stressed plants. Glyphosate alone or as tank mix with phenoxy herbicides, followed by SpraySeed®, effectively controls this weed. Alternatively, glyphosate followed by ParaTrooper® gives good control.

Grazing

Graze infested areas heavily and continuously during spring, summer and autumn. It is unlikely that the oxalate levels in tar vine could cause toxicity, but it may be an issue if stock are in poor condition when introduced to the field. Remove stock if toxicity is suspected.

Burning residue

Tar vine seeds can be destroyed by burning, but sufficient crop residues are needed to achieve a uniform burn.

Cultivation

Strategic cultivation (for example, mouldboard ploughing) to bury seed is effective. However, buried seed may remain dormant, so it is important to ensure buried seeds are not immediately returned to the surface in subsequent years.