RAGWORT appears to be an increasing problem in grassland throughout the west of Scotland. This tall, yellow weed (senecio jacobaea) is highly poisonous to all grazing stock but cattle and horses are particularly susceptible. Sheep and goats are more tolerant.

Stock does not usually consume ragwort when there is adequate grass available, but when pastures are very bare animals can be forced to do so.

Dead and dying ragwort is more attractive to stock, and remains poisonous. Ensiled ragwort is highly dangerous and can contaminate a whole silage clamp.

Ragwort poisoning occurs due to the presence of alkaloids which attack an animal's liver. Poisoning may be acute where a large quantity is eaten in a short period but is more commonly chronic and cumulative.

As for controlling ragwort, low populations can be hand-pulled, and pulling machines have been developed for higher infestations. Cutting is not recommended as it can promote perennialisation which results in vigorous growth the following year.

The best time to treat ragwort with herbicides is from late April to late May when second year and older plants are still at the rosette stage and new seedlings have emerged. This is not practical on pasture scheduled for cutting for hay or silage production. The best time to treat these fields is now.

Herbicide treatment at any time from mid-September to mid-November can give good results provided the weather is mild.