What is horehound?

(Marrubium vulgare)
Flowering Horehound Generic Weed Distribution Map
  • Horehound is a weed of crops and pasture. Horehound is also a significant environmental weed of disturbed bushland.
  • Horehound is a declared weed under the Tasmanian Weed Management Act 1999. The importation, sale and distribution of horehound are prohibited in Tasmania.

How to identify horehound

  • Horehound is a branching, perennial (long-lived) plant growing to a height of about 80 cm.
  • The stems and lower surface of the leaves are covered with white woolly hairs, giving the plant a silvery appearance. The leaves have a "crinkly" appearance and the leaf margins have rounded teeth. The white flower clusters are densely packed, forming balls of flowers that surround the upper stems at each leaf node.
  • Most seed germinates after autumn rains but some germination also occurs through winter into spring. Established plants flower over several months during summer and autumn and new growth is produced each year in autumn and spring.
  • For help in identifying horehound, search the Dennis Morris Weeds and Endemic Flora Databse. If you are still in doubt about the weed you are dealing with, contact your Regional Weed Management Officer on 1300 368 550 for help.

Paddock infested with horehound
Image top: horehound in flower (Image: Tasmanian Institute of Agricultural Research)
Image above: horehound infested paddock (Image: Tasmanian Institute of Agricultural Research)

Horehound in Tasmania

  • Horehound is found throughout Tasmania, and is most troublesome in the Midlands grazing areas (see map). Infestations of horehound occur on roadsides, waste areas, stockyards, dry banks, near farm buildings and on the site of old homesteads.
  • Horehound can contaminate sheep and goat fleeces by its dry fruits (or burrs), leading to significant losses in fleece value due to matting.
  • Horehound is also an important environmental weed due to its ability to invade disturbed native vegetation.

What is the legal status of horehound in your area?

The legal responsibilities of landholders and other stakeholders in dealing with horehound are laid out in the Horehound Statutory Weed Management Plan.

Use \Table 1 (Zone A municipalities) and Table 2 (Zone B municipalities) in the Horehound Statutory Weed Management Plan to find out whether your area falls in an eradication or containment zone.

Detailed management and control guidelines for horehound can be found in the Horehound Control Guide. Refer also to Herbicides for Horehound Control. For further information see DPIPWE's Weed Links and Resources.

See also

Horehound Control Guide
Horehound - Herbicides for Control
Horehound Statutory Weed Management Plan
Weed Links and Resources

Other useful links

Pest Genie
Weeds in Australia - Weed Management Guide

    Important Disclaimer
    To the extent permitted by law, the Tasmanian Department of Primary Industries, Parks, Water and Environment (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using information or material (in part or in whole) contained on this website.

Back Home