10 November 2011

Ragwort: what a fantastic plant for bees

Ragwort was in the news again earlier this year. I got interviewed on local radio about its value for moths (not a very rewarding experience, since the presenter seemed unable to get past his amusement at the idea of anyone actually being interested in moths). And environment minister Richard Benyon attracted a bit of attention with some ill-conceived Facebook comments about his hatred of Ragwort. Shortly after that episode, I happened upon this clump of Ragwort in full flower in the middle of one of my local SSSIs:

How many bees can you see on the flowers?


There were at least 50, which I've carefully highlighted in the second version of this photo, and they were having a fine old time necking nectar and perusing pollen:

On this occasion I didn't capture any to check the species; there were several involved, but I'm pretty sure that many of them were the solitary ground-nesting bee Lasioglossum calceatum (this one, with its long antennae, looks like a male): 

Now, Ragwort can cause problems, being toxic to grazing mammals when consumed in large quantities, and where it poses a genuine risk to these animals it needs to be controlled. But in areas where grazing animals aren't an issue, Ragwort provides a valuable resource for many, many insects, including at least 30 insects and 14 fungi that are entirely dependent on the plant, plus the huge numbers of insects that visit the flowers for pollen and nectar, as shown above.

The controversy over the rights and wrongs of ragwort has raged for years now, and the claims for its harmful effects have often been widely exaggerated. There's plenty of good information about Ragwort available nowadays, not least in DEFRA's own Code of Conduct, so there's not really any excuse for continuing to demonise the plant. Like most entomologists, I remain pleased to see Ragwort in all non-grazing-mammal contexts, and hope to see many more plants covered in the buzzing of contented bees, flies, beetles and butterflies - the sheer exuberance of the bees in the photos above were one of my year's wildlife highlights.

Good sense on Ragwort is available from:


2 comments:

Richard Jones said...

Narrow-leaved ragwort is steadily moving into East London brownfield sites. It is always abuzz with stuff.

Martin Harvey said...

John Robertson has been in touch to highlight a recent blog post of his, a thorough investigation of one of the sources often used for data on the number of horses that suffer from ragwort poisoning each year. It makes for interesting reading:
The Poison Garden

It's probably worth re-emphasising that I'm not claiming that ragwort poses no threat at all, just that the threat is often exaggerated and that it needs to be balanced against the great benefits of ragwort for supporting biodiversity.