A full Andrena fulva sunbathing near the tree.
Outside the blooming season, which lasts a few weeks from April to May, the tree growing buds are covered on black aphids that in june produce a sweet sap, loved by bumblebees, especially Bombus terrestris and Bombus hypnorum. I have also seen Bombus pratorum feeding on the nectaries at the end of the leave stalks. Aphids also attract scores of ladybirds. The cherries themselves are prized by wasps - and birds.