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Holtspur Bottom Butterfly Reserve


cinnabar moth caterpillar on ragwort flower

Cinnabar moth caterpillar on Ragwort flower.

We have two kinds of ragwort on the reserve at Holtspur Bottom, Common Ragwort (Jacobaea vulgaris or Senecio jacobaea) and Hoary Ragwort (Senecio erucifolius).

Common Ragwort is the foodplant of at least 77 species of insects: 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.

Why then does part of our management of the reserve involve reducing the numbers of this valuable plant? Simple. Common Ragwort is deadly to horses, and may be injurious to other grazing animals. Our immediate neighbours have horses and both they and other local livestock owners are concerned that our ragwort could seed onto their land and poison their stock. Although Hoary Ragwort isn't poisonous in the same way, from a distance the two species are indistinguishable, and we feel our neighbours will be reassured if they see fewer "ragwort" plants of any kind on our reserve. Similarly, if our hay were free of ragwort we could sell it and significantly offset the costs of mowing our meadows. At present, we have to pay to have the hay removed.cinnabar moth

Ragwort also tends to crowd out other plants if not controlled, meaning our meadows are less useful to butterflies and moths. Ragwort has been a problem ever since we took over management of the reserve. We normally organise work parties of volunteers during the summer to pull the plants out before they have chance to set seed, and occasionally, we try to remove some plants earlier in the year by digging them out. If you would like to join us in this back-breaking, but vital task, see the Information Boards on the reserve, or check the Holtspur Valley Events page for current dates. We can guarantee a warm welcome!

You may also be interested in

pdf iconPlantlife's Position statement on Ragwort

pdf iconBuglife: Ragwort: Noxious weed or precious wildflower?

pdf iconBuglife: Ragwort: Insect fauna in detail

pdf iconDEFRA: Code of Practice on Ragwort

pdf iconEnglish Nature: Information note on Common Ragwort


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