My Sky Rocket junipers are declining. To me it looks like mite damage accompanied by winter damage. The top of the plant is still healthy looking. There are spider mites present. It does not resemble phomopsis, but could be phytophthora. Please let me know what you think.
I checked Diseases of Trees & Shrubs by Sinclair, Lyon and Johnson and Juniper virginiana does not get phytophthora (or at lease this good authority does not list that disease.) It does list a number of other diseases including blight, canker, phomopsis, among many others.
The HortSense website of WSU Cooperative Extension mentions Juniper webworm, which creates heavy webbing, which could resemble mite webbing.
Of course it could be winter damage, like you guess or nitrogen deficiency if the Ph is high (near a lot of concrete?), or salt damage (from melting ice in past winters?).
You should take a sample in to a Master Gardener clinic. If they do not know the cause, you can ask that they “submit it to the diagnostic center at the Center for Urban Horticulture.”
Locate a Master Gardener Clinic within King County at this website.