In reply to Chris the Tall:
>
> You don't tend to get midges on limestone - not sure if its due to the acidty in the soil, the bracken, or just that they don't like the polish
They're not strong enough for limestone. I can confirm that I spent a cracking evening bouldering at Raven Tor yesterday. Clear skies, a cool breeze, perfect conditions and not a midge (or fellow boulderer) in sight. Lovely.