Alex Hyde / Greenbottle (Lucilia caesar) feeding on Hemp agrimony (Eupatorium cannabinum) Strumpshaw Fen, Norfolk, UK, September.

Alex Hyde / Hoverfly (Helophilus pendulus) feeding on Hemp agrimony (Eupatorium cannabinum) Strumpshaw Fen, Norfolk, UK, September.

Stephen Dalton / Hoverfly (Eristalis arbustorum) on Hemp Agrimony (Eupatorium cannabinum) Sussex, UK

Stephen Dalton / Hoverfly (Eristalis arbustorum) taking off from Hemp Agrimony (Eupatorium cannabinum) Sussex, UK

Nick Upton / Hemp agrimony (Eupatorium cannabinum) with flower buds just opening, Creech Heath, Dorset, UK, July.

MYN / Marko Masterl / Hemp-agrimony (Eupatorium cannabinum) in flower, Slovenia, Europe, August. meetyourneighbours.net project

Ernie Janes / Small tortoiseshell butterfly (Aglais urticae) on Hemp agrimony (Eupatorium cannabinum) England, UK, August.

Ernie Janes / Small tortoiseshell butterflies (Aglais urticae) feeding on Hemp agrimony (Eupatorium cannabinum) England, UK, August.

Ernie Janes / Small tortoiseshell butterflies (Aglais urticae) feeding on Hemp agrimony (Eupatorium cannabinum) England, UK, August.

Nick Upton / Peacock (Aglais io) butterfly nectaring on Hemp agrimony (Eupatorium cannabinum) flowers, Strumble Head, Pembrokeshire, Wales, UK. August.

Nick Upton / Giant tachinid / Yellow-faced fly (Tachina grossa) nectaring on Hemp agrimony (Eupatorium cannabinum) flowers, Strumble Head, Pembrokeshire, Wales, UK. August.

Will Watson / Hemp agrimony (Eupatorium cannabinum) on white background, Herefordshire, England, UK. August. Focus stacked under controlled conditions.

Will Watson / Hemp agrimony (Eupatorium cannabinum) on white background, Herefordshire, England, UK. August. Focus stacked under controlled conditions.

Nick Upton / Hemp agrimony (Eupatorium cannabinum) flowering in a dense stand in a hedgerow, Dorset, UK. August.

Nick Upton / Hemp agrimony (Eupatorium cannabinum) flowering in a dense stand in a hedgerow, Dorset, UK. August.

Philippe Clement / Female Tapered drone fly / Dronefly (Eristalis pertinax) pollinating and feeding on nectar from Hemp-agrimony (Eupatorium cannabinum) flower, Belgium. August.

Philippe Clement / Male Hornet mimic hoverfly (Volucella zonaria) pollinating Hemp-agrimony (Eupatorium cannabinum) flower in summer, Belgium. August.

Philippe Clement / Rosy footman moth (Miltochrista miniata) feeding on Hemp agrimony (Eupatorium cannabinum) flower, Belgium. August.

Philippe Clement / Red admiral (Vanessa atalanta) feeding on nectar from Hemp-agrimony (Eupatorium cannabinum) flower, Belgium. August.

Philippe Clement / Red admiral (Vanessa atalanta) pollinating Hemp-agrimony (Eupatorium cannabinum) flower, Belgium. August.

Nick Upton / Hemp agrimony (Eupatorium cannabinum) flowering on a woodland edge, Bath and Northeast Somerset, UK, September.

Nick Upton / Small white butterfly (Pieris rapae) nectaring on Hemp agrimony (Eupatorium cannabinum) flowers in a woodland ride, Catcott Lows National Nature Reserve, Somerset, UK, September.

Nick Upton / Large tiger hoverfly / Sun fly (Helophilus trivittatus) nectaring on Hemp agrimony (Eupatorium cannabinum) flowers in a woodland ride, Catcott Lows National Nature Reserve, Somerset, UK, September.

Linda Pitkin / Hemp-agrimony (Eupatorium cannabinum), Basingstoke Canal, Surrey, England, July.