This willow tree is covered in these insects.
The leaves and the ground around the tree is shiny and sticky from all the aphids excrement.
On an apple tree
These dark 'scale insects' coat the lower limbs of a willow and their secretions seem to be attracting hornets.
Found on willow tree, many clusters, did not have hand lens at time
Aphid mummies with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummies with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummies with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummies with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummies with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummy with Pauesia nigrovaria on a Salix fragilis tree.
Aphid mummies with emerged Pauesia nigrovaria on Salix alba tree.
Aphid mummy with Pauesia nigrovaria on Salix alba tree.
Aphid mummy with Pauesia nigrovaria on a Salix alba tree.
Fresh aphid mummy with Pauesia nigrovaria on a Salix x reichardtii tree.
Aphid mummy with Pauesia nigrovaria on a Salix fragilis tree.