Juniper gall midges.
This is the most informative article on juniper midge galls that I have seen yet.
http://coo.fieldofscience.com/2016/01/juniper-gall-midges.html
This is the most informative article on juniper midge galls that I have seen yet.
http://coo.fieldofscience.com/2016/01/juniper-gall-midges.html