busy as 2 bees

Bombus lucorum
White-tailed Bumblebee on left
and
Bombus pascuorum
Common Carder Bee on right
on
Centaurea nigra
Lesser Knapweed, Common Knapweed and Black Knapweed

a brief morning walk, followed by a trip to the farmer's market and some messages in town
an afternoon of household chores and a walk around Slateford Dell
a meal with S at Kilderkin
a meet up with Dave H, Meles and Cancarrier in Tourmalet to toast a blip wedding
a nip into the Windsor Buffet to catch the Italy/England game
another in the New Town
a late taxi home

I could do with a bit of help identifying something I've seen happening to a few nettles around and about...?