Ragwort management

July 2023

What is ragwort?

Ragwort (Senecio jacobaea) is native biennial which is a food source for a wide range of insects. Ragwort is a tall erect plant to 90cm (3ft) bearing large flat-topped clusters of yellow daisy-like flowers from July to October. It has finely divided leaves with a basal rosette of deeply-cut, toothed leaves.  The plant is usually a biennial (living only two years and flowering in its second year) but damage to the base of the plant can make the plant behave like a perennial (living indefinitely), as new rosettes are formed.

Is it dangerous/poisonous?

Ragwort is poisonous to some types of livestock, especially horses and the toxicity remains in the plant after it’s been pulled. In a grazing situation you often see fields with grazing animals and ragwort present because animals seem to recognise the yellow flower and positively avoid it. However, once the ragwort is cut and dried it resembles the rest of the hay and animals find it hard to differentiate. Therefore we believe that sensible management of the site is the approach we will take to ragwort.

Biodiversity value

It is an important food plant for common broomrape Orobanche minor, 14 species of fungi and a range of invertebrates, 177 invertebrate species have been recorded feeding on ragwort nectar. An information note produced by English Nature suggests that ‘it is the food of at least 77 species of insect herbivore [including five ‘red data book’ and eight ‘nationally scarce’ species]: 27 species of moth, 22 species of thrip, 13 species of bug, nine species of flies and six, species of beetle. The most famous is the cinnabar moth whose yellow and black banded larva can defoliate entire plants’.  So it’s biodiversity value shouldn’t be underestimated!

Our approach

The long term approach of rewilding the site will reduce the ability for the ragwort to establish because the grass sward will close over and when the woodland matures it further limit the ability of the ragwort to exist. We have no livestock on site however cattle and sheep do graze in neighboring fields and we have an arable crop field directly adjacent to the main concentration of ragwort.

In the short term we have pulled ragwort from various areas of the site to minimise its spread over the short term. Next year when the presently dormant seeds grow and flower will will have a better handle on it and will allow it to grow and be a food plant for the insects on site.