Females lay eggs where the bark is loose or cracked, especially on dead center canes.
Heavy infestations cause wilting, bark cracking, and branch dieback.
A better management practice is to prune out all larger center trunks. It may take a couple of seasons to do this. Pruning will have the added benefit of promoting new growth, resulting in more flowers and a more shapely plant. Ground cover junipers can become very susceptible to Phomopsis tip blight and Kabatina blight when the plants get too much shade. This was very evident last week where Junipeius horizontalis was used under a crabapple tree and the increasing shade level has caused the juniper to turn brown.