Ragwort and Horse - A Poisonous Plant Toxic to Horses

Ragwort and Horses. A Poisonous Combination

Ragwort is a common weed that grows throughout the British Isles. Ragwort and horses has always been a problem for horse owners.

Ragwort thrives on wasteland, road verges and railway land and it easily spreads to grazing land and pasture.

Recently though, it has become apparent that ragwort may be getting out of control and posing a real threat to the horse population.

Poor quality & poorly managed horse pasture is prone to ragwort infestation.

Closely growing grass sward prevents ragwort growth but when the grass becomes thinned out, due to poaching or over grazing, the seeds are able to germinate in the exposed soil.

Most animals will avoid eating ragwort as long as they have an alternative source of good food.

This can be a problem on sparse, overgrazed pastures where ragwort can thrive.

There are reports that horses can acquire a taste for ragwort, especially if there is little else to eat.

Ragwort - Plants Toxic to Horses

Dried Ragwort and Horses; The Danger Zone

When cut or wilted (ie; when making hay or haylage) ragwort loses its bitter taste and becomes palatable to horses.

Drying does not destroy the toxins and dried grass, hay and haylage are common sources of ragwort poisoning.

Ingestion of the pyrrolizidine alkaloid toxin contained in ragwort usially results in the delayed onset of chronic, progressive liver failure.


Ragwort the Facts …
  • Ragwort kills livestock and horses by causing irreversible liver damage.
  • The horse has to ingest enough to cause the damage, and quantities required can vary.
  • All UK landowners have a duty to control ragwort.
Ragwort is normally biennial.

It produces small rosettes in the spring and flowers from July onwards, in its second year.

Effects of ragwort poisoning

Ragwort toxins are cumulative and it is common for ragwort poisoning to occur following consumption of small quantities of the plant over a long period of time.

Development of the disease can be delayed from four weeks to six months after eating the plant.

Different types and sizes of horses have different levels of susceptibility to the toxin.

Symptoms of ragwort poisoning :

  • weight loss
  • poor and staring coat
  • staggering gait
  • impaired vision
  • inability to swallow
  • paralysis
If long stems of ragwort are cut, the plant behaves like a perennial, (flowering every year)

Each ragwort plant produces 150,000 seeds that remain viable for years. It is easily spread by air turbulence created by passing traffic.


DEFRA & UK Law. The Weeds Act and The Ragwort Control Act

Ragwort is one of five injurious weeds covered by the provisions of The Weeds Act 1959.

Ragwort and horses is a poisonous combination but so to is ragwort and ponies, donkeys and other livestock.

Ragwort causes liver damage, which can have potentially fatal consequences.

Under the Weeds Act 1959 the Secretary of State may serve an enforcement notice on the occupier of land on which injurious weeds are growing.

This will require the occupier to take action to prevent the spread of injurious weeds.

The 1959 Weeds Act specifies five injurious weeds:

  • Common Ragwort
  • Spear Thistle
  • Creeping of Field Thistle
  • Broad leaved Dock
  • and Curled Dock.

In 2003 the British Horse Society sponsored a Private Member’s Bill to amend the Weeds Act

BHS hoped to provide for a code of practice to prevent the spread of ragwort. The UK Government supported the Bill and the Ragwort Control Act came into force in February 2004.

Defra worked with the British Horse Society and other stakeholders, including English Nature, Wildlife Trust and ADAS to produce the code of practice, which was launched at the Royal Show in July 2004.


Who to contact if you are concerned about ragwort spreading onto your pasture

The occupier or landowner of land where ragwort is found growing is responsible for controlling this poisonous plant.

Horse owners are often concerned about ragwort spreading from nearby fields or roadside verges onto their horse’s grazing, Defra advise that the horse owner initially approach the land owner/occupier to request that they take steps to prevent the weeds from spreading.

If this approach is unsuccessful, the problem should be reported to Defra using the complaint form on the DEFRA website:

  • Weeds Act 1959 – Complaint Form (WEED2/WEED2A).
  • The completed form should be sent to: Natural England, Injurious Weeds, Customer Services, PO Box 2423, Reading, RG1 6WY.
  • alternatively they can be contacted by email using: iss.reading@naturalengland.org.uk or by telephone on: 0300 060 1112.

High priority is given to complaints where ragwort is encroaching upon land used for: grazing or keeping horses.

Contact details for reporting ragwort problems on roads or railways:
Railway land and embankments
Network Rail
40 Melton Street, London, NW1 2EE
Tel: 08457 114141
Motorways and trunk roads
Highways Agency, Federated House
London Road, Dorking, Surrey, Rh3 1SZ
Tel: 0300 123 5000