Ragwort (Focus - July)

A distinctive and common flower of rough grassland at this time of year is ragwort. It has a fine head made up of bright yellow daisy-like flowers, held on a tall stem with deep green, much divided leaves. Where it grows, it is often numerous and can create impressive seas of yellow in a field.

Ragwort attracts numerous insects to its flowers: 200 different species have been recorded. Gatekeeper butterflies are often seen nectaring on the flowerheads. Ragwort is a foodplant for the distinctive black and yellow striped caterpillars, or larvae, of black and red cinnabar moths. Often, the larvae are present in such numbers that they soon strip the plant of all leaves and have to troop off to an adjacent plant to keep feeding. The leaves have an unpleasant taste which transfers to the feeding larvae. The distinctive markings in them warn potential predators that they are unpalatable and, although some birds do take them, the larvae make no effort to hide as they feed.

The unpalatability of the plant is due to a number of alkaloids in its tissues, making it poisonous to some animals, notably horses and cattle, although proven poisoning cases are rare. Because of the unpleasant taste, animals will avoid eating the live plant, but a problem arises if ragwort gets mown and picked up in hay, which is subsequently fed to stock.

This is why, each July, members of the Tisbury and District Natural History Society (and others) get together to remove ragwort from the Community Meadow before seed sets and the hay is cut. Leaving the ragwort in the hay would make it worthless and only fit for disposal. We pull the whole plant up by the roots which, as it is a biennial, are relatively shallow. The technique is to get good grip with gloves, low down on the stem, and then lean back to extract the plant. Many hands make light work, and it does seem as if there are fewer plants to pull each year.

As the annual mowing and removal of hay depletes the fertility of the soil, so the floristic diversity of the meadow increases, giving more flowers for us to enjoy. This in turn can reduce the amount of bare earth between the plants in the sward, which restricts the opportunities for ragwort seed to germinate and grow next season. Hopefully, this is a virtuous cycle which will make life easier each year, but ragwort will always be there to provide colour for us to enjoy and flowers for insects to feed on for several weeks before removal.

​Andrew Graham