Killer Weeds – Ragwort & the Groundsels
Ragwort and Groundsel are closely related both being members of the large Senecio family. More than 30 toxic factors have been identified in the Senecio species, these are mostly alkaloids with a pyrrolizidine base. Grazed in large quantities they are fatal. So, diligence is required as well as readiness with the ragwort fork. The Senecio family are also thought to cause cancer when grazed in small quantities, as they are extremely toxic to the liver.
Their attractive yellow daisy flowers identify the Senecio family, flowering in the summer months between June and October.
Common Ragwort – Senecio jacobea
A biennial attaining a height between 60 to 100cms (2ft to 3ft 6inches). Found growing in dry grassland. Known in Scotland as ‘Stinking Willy’ referring to its foetid smell.
Country women used Ragwort to induce abortions. The results were often fatal. Many a mare with a history of miscarriage on closer inspection had Ragwort growing in her field. This may seem unbelievable after all the publicity and articles about this killer weed.
Under normal conditions when grazing is plentiful horses are less likely to eat Ragwort or Groundsel, as it is unpalatable. During a dry summer or drought conditions in the early Autumn when grazing is scarce there is a real danger of Ragwort being grazed. More worrying is the fact that drying preserves the dangerous alkaloids in Ragwort & the Groundsel family. They are just as dangerous dried in hay as when eaten fresh.
Groundsel – Senecio vulgaris
An annual shorter than Ragwort lacking the foetid smell, rich in toxic alkaloids, 30 to 38cms (12 to 15inches) in height. A weed that often emerges on cultivated land, dispersing its seeds in the wind.
Symptoms of Poisoning
Horses showing signs of poisoning rarely recover. These may not appear for several weeks. Symptoms include staggering, unaccounted for outbreaks of colic, constipation with intense straining, occasionally diarrhoea, frenzied excitement and rapid pulse.
Control – Ragwort Fork or Chemical?
There is only one thing to do and that is to totally eradicate these noxious weeds from your land. In the UK there is an obligation, set out in a statutory code of practice, to prevent the spread of ragwort.
Digging and burning can be successful, but care must be taken that as the green material is burnt and the seeds not left intact to disperse. Wilted or dead plants left lying on the land to be eaten by the horses, defeats digging them out in the first place. A ragwort fork is the most effective, and environmentally friendly, way to control ragwort as long as it is ensured the plant is fully removed
There are environmentally friendly chemical sprays, specifically designed to kill ragwort. Biotech manufacture an innovate citronella based product, “Barrier H” which is fast acting and can be used at any stage of growth.