Quick Facts

Quick facts

  • Wild Carrot (Daucus carota) is native to Europe, south-western Asia and northern Africa, and was deliberately imported to the colony of Sydney between 1786 and 1798 for food production.
  • A bi-annual or sometimes annual herb, 0.3-2 m tall, with course fern-like leaves to 280 mm long, flower heads containing 750-5000 small white or light pink flowers, 50-150 mm in diameter across, arranged in compound umbels (umbrella-shaped groups of flowers).
  • Spread only by seed, two seeds per fruit, with each fruit 2-4 mm long, covered in rows of short spines only the apical ones hooked, with single plants cable of producing 1,000-40,000 seed that are viable for a seven-years or longer.
  • Growing in cool to warm temperate climates found on roadsides, disturbed sites and agricultural areas, invading open ground.
  • Competes with native plants, sown pastures, crops and commercial carrot crops for resources, and also harbours pests that will attack commercial carrot crops, and can also taint milk if dairy cows consume large quantities.
  • To control Wild Carrot, seed production should be prevented and the soil seed bank exhausted. A combination of machine, manual and grazing treatments can be used to prevent seed set and exhaust the soil seed bank, and plants are also susceptible to herbicide treatment.

What Does It Look Like?

What is it?

Wild Carrot (Daucus carota) is an erect biennial herb that grows 0.3 to 1.5 -2 m high. The roots of wild carrot are usually white, unlike cultivated edible carrots that are commonly orange. Wild carrot roots are also smaller than the cultivated edible carrot roots. Its stems are ridged lengthwise and normally covered with many short rigid hairs, about 1-2 mm long, but sometime can be hairless. The leaves are up to 280 mm long, mostly growing in a basal rosette (circular arrangement at base), with a few alternately arranged up the stem. Leaves are deeply divided, giving a fern-like appearance. The leaf stalk is 15-45 mm long and sheathes the stem at its base. When crushed, the plant produces a characteristic carroty odour.

The flowers are arranged in tightly held compound normally flat-topped to slightly rounded umbels (umbrella-shaped groups of flowers), with each compound umbel 50-150 mm in diameter across, held at the top of the main flowering stem (a peduncle). Each peduncle gives rise to 30-60 but sometimes up to 100, individual secondary flowering stems (called secondary peduncles or rays), ranging from 10-100 mm in length. At the top of the main flowering stem, below the secondary stems, arise many long (up to 50 mm) thinly branched bracts (leaf like structures). At the top of each secondary flowering stem, arise individual umbels (also known as umbellets). At the base of the umbellets a second set of similar but smaller thinly branched bracts arise. Each umbellet is about 10-30 mm in diameter across, with about 25-50 small flowers, but sometimes up to 100 or more on larger plants, with each flower on an individual pedicel (individual flowering stalk) ranging from 2-15 mm long. The flowers have five petals that are unequal in size. Flowers range from 1.5-4 mm in diameter, with some larger petals up to 2.5 mm long.  Flowers are white, yellowish or pink. The inner flowers at the very centre of the compound umbel are normally sterile and are commonly black or dark purple to purple. After fertilisation, the flower head folds up and has a “birds nest” appearance.

The small fruits each contain two seeds. These fruit (2-4 mm long) are covered in rows of short spines, with only the apical ones barbellate, primary ribs with a row of short hairs and the whole inflorescence (flowering structure) folds inward as the fruit ripen (Western Australian Herbarium 1998-; Walsh & Entwisle 1999; Navie 2004; Harden 2007).

Recognition: This species can normally be recognised by the combination of the following characters; a small or large herb; growing in seasonally damp fertile areas; first year rosette foliage growth is very similar to the garden carrots with a carroty smell when crushed; green ribbed stem normally with many short hair 1-2 mm long (sometimes hairless but always ribbed); fern like stem leaves to 280 mm long, also with a carroty smell when crushed; flat umbels of white, yellow or pink flowers, sometimes with the inner flowers at the very centre of the compound umbel being black or dark purple to purple. For further information and assistance with identification of Wild Carrot, contact the herbarium in your state or territory.

Flower colour

Yellow or White or Pink.

Growth form (weed type/habit)

Herb

Where it currently grows? Preferred habitat

Wild Carrot prefers full sun in fertile moist soils in areas with some disturbance, normally around populated areas (Navie 2004). It is a weed of disturbed sites such as crops, pastures, gardens, roadsides, waste areas, and known to occur in disturbed natural vegetation (Western Australian Herbarium 1998-; Navie 2004).

Are there similar species?

Wild Carrot differs from the native Daucus glochidiatus in having a large flat-topped inflorescence with numerous many-flowered umbrella-shaped flower clusters and fruit with short hairs and spines, whereas the native species has an inflorescence of a few small clusters, each with a few flowers, and fruit with hooked bristles (Western Australian Herbarium 2007).

Wild Carrot differs from Poison Hemlock (Conium maculatum) in having leaves with carroty smell when crushed; ribbed stem, normally with many short hairs 1-2 mm long, and just green in colour; umbels with dark flowers in the centre (normally), whereas Poison Hemlock has; unpleasant-smelling foliage; stem without ribs, hairless, and green with purple blotches; and flowers all one colour.

Fennel (Foeniculum vulgare) has a similar habit but narrower leaf segments than Wild Carrot, and foliage that smells of aniseed when crushed, and yellow flowers, not white or cream to light yellow like Wild Carrot.

Why Is It A Weed?

What are its impacts?

Wild Carrot (Daucus carota) is primarily a weed of roadsides, disturbed sites and agricultural areas, invading open ground.

Agriculture: Wild Carrot may harbour pests that will attack commercial carrot crops. Wild Carrot can also taint milk if dairy cows consume large quantities (Dale 1974), and can dominate pastures competing with and replacing desired plants. Hybridisation with the commercial plant can result in poor seed production (Dale 1974). In Japan, Umehara et al. (2005) made hybrids between wild and cultivated carrots and showed that they can produce vigorous hybrid offspring.

NOTE: Wild Carrot is the same species as the commercially grown plant. However, wild and cultivated carrot are labelled as different subspecies.

Wild carrot is: Daucus carota spp. carota.

Cultivated carrot is: Daucus carota spp. sativa.

Native ecosystems:  Wild Carrot poses a threat to recovering grasslands, competes with native grasses and herbs for resources as it matures faster and grows larger than many native herbs or grasses. It can also spreads into disturbed natural communities and can also occasionally invade less disturbed native vegetation. In the US it has been observed to germinate readily after fires and can be particularly persistent in soils with high clay content (Eckardt 1987 in Washington State Noxious Weed Control Board 2007).

Urban areas:  Can grow on disturbed areas on urban fringes and roadsides.

How does it spread?

Wild Carrot disperses by seed only, and not by vegetative structures such as rhizomes or perennial roots. Each plant produces thousands of seeds from 1,000-40,000 seeds.

Seeds can be spread by natural means over short distances by wind and water and the hooked seeds attach to and are dispersed by wild animals. Seeds also spread by people, sometimes long distances, on clothing, or via mowing/slashing, vehicle movements, (Tanner 2007), in contaminated soil, attaching to domestic animals, or as a contaminant of farm produce.

What is its history in Australia?

Wild Carrot is known to have been deliberately imported to the colony of Sydney as seed for food production between 1786 and 1798 by Sir Joseph Banks (Frost 1993). It was recorded in Robert Brown's 1802-4 list of introduced plants for the Port Jackson area (Groves 2002).

How To Manage It?

Best practice management

The biology of Wild Carrot is a critical consideration in preventing or controlling wild carrot infestations. The ultimate goal of controlling wild carrot, regardless of the method, should be to prevent seed production because seeds are the only means of reproduction, and they are relatively short-lived in the soil (Stolarczyk 2007). However, healthy wild carrot plants can produce as many as 1,000-40,000 seeds per plant, and seeds can live and germinate over a seven-year period or longer.

Herbicide application (chemical control) is not normally the best option for established wild carrot on farms. Grazing management and mechanical clipping plants before they set seed is likely to be more effective and economical. Viable seed will remain in the soil profile and be viable for a seven-year period or longer, so control options requires long term commitment.

Chemical control: Wild Carrot can be controlled by herbicides at three stages of growth: plants germinated before winter can be controlled with early pre-plant, pre-emergence or post-emergence herbicide applications; established plants with autumn herbicide applications; and seedlings with pre-emergence or post-emergence herbicide applications. Established plants are generally more difficult to control than seedlings (Stolarczyk 2007).

Non-chemical control: Physical control: Hand-pulling or mowing during the first year, when the plants are 18 to 26 cm tall, can be effective (Eckardt 1987 in Washington State Noxious Weed Control Board 2007).

Competition and management: Mowing or clipping at late flowering stage reduces wild carrot size and seed production. Plowing and planting a cultivated crop for two years may decrease infestations. Frequent cultivation promotes seed germination, which depletes the soil seed bank and destroys seedlings before they can mature and reproduce (Muenscher 1980). Grazing – sheep, horses and cattle will graze wild carrot.

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au 

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Wild Carrot is most commonly a biennial herb, requiring two years to complete its life cycle. During the first year of growth, the plant will germinate normally in spring  producing only rosette leaves that die back over winter, with the taproot storing the food needed to begin growth in the next season. During the second year of growth a stem will emerge and the plant will flower any time from spring to autumn but more commonly in summer, and then set seed. However, some plants can flower and set seed during the first year of growth. Once the plant has set seed, it will die and no longer be a problem itself, but the many seeds produced (up to 40,000) germinate and form new plants and possible problems in the future. The seeds usually germinate within two years of dispersal, but may persist in the soil for up to seven years or longer (Stolarczyk 2007). Flowering may occur within six weeks of germination (Dale 1974).

Where Is It Found?

Which states and territories is it found?

NSW, QLD, SA, TAS, VIC, WA.

What areas within states and territories is it found?

In New South Wales it occurs in all coastal, tableland and western slope regions (Harden 2007). In Queensland it occurs in the south-east corner (AVH 2007). In South Australia it occurs near the coast in the south-east corner of the state (eFlora of South Australia 2007). In Tasmania, it occurs in the Hobart area and along the north coast (AVH 2007). In Victoria it occurs along the south coast, in the eastern highlands and midlands and in the Riverina (Walsh & Entwisle 1999). It has been recorded in the south-west of Western Australia, particularly in the Albany area (Western Australian Herbarium 1998-).

Where does it originate?

Wild Carrot is native to Europe, south-western Asia and northern Africa (Navie 2004).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

Not declared in any state or territory.

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Daucus carota

Other scientific names (synonyms)?

 

Does it have other known common name(s)?

Common Carrot, Queen Anne's Lace

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