Dandelion

Scientific name: Taraxacum officinale

Dandelion flower

Dandelion in flower

Dandelion

Dandelion

Dandelion in pasture

Dandelion seed head

Dandelion

  • Key characteristics
  • Biology
  • Impacts
  • Control
  • Further information

  • Common perennial weed, recognised by the single, large yellow flower borne on top of a leafless, unbranched hollow stem
  • Stem rises from a flat rosette of basal leaves
  • All parts of dandelion contain a milky sap
  • Leaves are thin and smooth, growing from the crown with teeth pointing towards the base. Midribs are hollow towards the stem
  • Young plants have broad leaves with several points. Deep lobes do not appear until several leaves have grown
  • Seedlings have dark green, shiny, hairless leaves.

Origin

  • Native to Eurasia
  • Introduced to many other parts of the world, including Australia and North America.

Life cycle

  • Dandelion is a perennial weed which can flower from early spring into autumn, but flowering peaks in October
  • Seeds are dispersed by the wind. The seedhead is a characteristic ball of fluffy seeds – children tell the time by the number of puffs to blow them all off!

Benefits

  • Beneficial in droughts due to its deep root system which also brings nitrogen and other nutrients to the soil surface
  • Eaten as a vegetable in many parts of the world
  • Dandelion can be used for medicinal purposes – its constituents have antioxidant and anti-inflammatory activities
  • Roots have been used as a substitute for coffee.

Occurrence

  • Common in pastures, lawns and waste ground. Occasionally found in arable crops but is common in perennial crops such as lucerne
  • Most plentiful in Canterbury, where it often invades lucerne crops.

Impact on pasture

  • Thrives in dairy pastures
  • Dandelion reduces yields of agriculture crops, slows the drying of hay and acts as a host to pests and diseases.

  • Dandelion is difficult to control because pieces of leftover root from as deep as 20 cm can grow into new plants
  • Control is easier to achieve at the vegetative stage than at flowering stage.

Grazing management

  • Can be kept in check by sheep.

Chemical control

  • Chemical control measures are seldom warranted in pastures as dandelion is outcompeted in vigorous swards
  • MCPA or 2,4-D would provide sufficient  control, but clover suppression probably results in more loss of production than the presence of dandelion
  • Young seedlings may be more susceptible to MCPA than 2,4-D
  • Hexazinone can provide a varying degree of control in established lucerne but grazing the lucerne before treating with herbicide reduces the amount of lucerne leaf exposed to herbicide and thus reduces crop damage
  • Many of the selective pre-emergence and post-emergence herbicides used in field and horticultural crops help prevent seedling establishment or provide a varying degree of control of existing plants.

  • Popay I, Champion P, James T 2010. An illustrated guide to common weeds of New Zealand. New Zealand Plant Protection Society, Christchurch, New Zealand. 416 p.
  • Young S 2013. New Zealand Novachem agrichemical manual. Agrimedia Ltd, Christchurch, New Zealand. 767 p.