Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) has posted a notice advising homeowners to lightly shear boxwood and cedars now to reduce populations of leafminer larvae that would normally persist into 2018.
They note that annual summer sheering of these evergreen hosts can, over time, reduce infestations of leafmining pests, and also create a more full look by supporting increased lateral bud growth.
For more information, including images of leafminer damage, visit the OMAFRA posting here.