August 02, 2017 (0:00AM)

Ragwort is a frequent cause of plant poisoning of livestock in Britain.  It is one of the injurious weeds specified in the Weeds Act 1959, which gives the Minister of Agriculture, Fisheries & Food power to require landowners to take action within a specified time to prevent the weed from spreading to agricultural land. 

Ragwort seeds can be dormant in the soil for up to 20 years and each plant can produce up to 150000 seeds with a 70% germination rate.  Ragwort tastes bitter and livestock tend to avoid it on good pasture, but when grass is scarce the weed is eaten.  When cut, dried or wilted it loses its bitter taste but the poisons are not destroyed, consequently hay and silage are common sources of ragwort poisoning

Ponies and cattle, particularly young animals, are more susceptible than other livestock.  Ragwort acts as a cumulative poison and can eventually destroy the liver; a small intake over a long period is as damaging as a single large intake.  Chronic symptoms are loss of condition, poor appetite, constipation, sunburn and jaundice.   Nervous signs can develop such as restlessness and uncoordinated movement, the appearance of blindness, pressing heads against solid objects, abnormal gait.  Death can follow between a week and several months.

Ongoing control of Ragwort is essential to prevent ragwort poisoning.  It typically flourishes on open patches in poor grassland and will not easily establish in dense vigorous pasture with controlled grazing.  If you have a small infestation, a short term method of control is by digging or pulling (poisonous so always wear gloves).  To prevent seed dispersal this needs to be done before flowering has completed, and is easier in the spring after heavy rainfall when the ground is soft and the plant immature.  Ragwort can regenerate from root fragments and digging out the entire plant is more effective.  Simply cutting at early flowering stage reduces seed production but encourages more vigorous regrowth.

If you have a large infestation, and/or to provide a more long term solution, two applications of weedkiller are required.  The first application can be either in late April or May, or in October before frosts damage the foliage.  The second application should be made in late April the following year.  In all cases removal of dead plants is essential and all paddocks should be sprayed at the same time to avoid re-infestation.  Spot treatment with a systemic weedkiller using a knapsack sprayer, brush or weed wiper brush is effective and less damaging to the environment.  Please remember to follow product instructions regarding spraying weather conditions and exclusion of livestock from the treated area for the specified period.

If you believe an area of unchecked ragwort is causing a threat, you should first ask the occupier of the land to remove it.  If this is unsuccessful write to:

England                      the nearest Ministry of Agriculture Fisheries & Food Regional Service Centre
Wales                         the nearest Welsh Office Agriculture Dept
Roadside verges        Local Authorities will usually take action