Tried to pick some plums yesterday. Very few about, normally I have so many I don't know what to do with them. There were very large black flies gorging on those I could reach along with some wasps. I don't normally have too much of a problem with wasps and I've never in 16 years in this garden had huge black flies feeding off them. They were as big as bluebottles but couldn't have been as I always thought bluebottles fed on dead creatures. Anyone know what the flies are and why they're here this year for the first time? Yuk, they are disgusting.