Answer: It's really difficult to diagnose a plant problem without seeing it, but my experience with junipers leads me to believe that old age, combined with root rot has overtaken your plant. Before you do anything drastic, though, I'd highly recommend you snip off some of the affected plant parts, place them in a plastic baggie and take them to your local cooperative extension office. With the aid of a microscope they can either confirm or eliminate diseases such as root rot. Helpful folks there can also make suggestions as to what you can do for your juniper.
WSU Snohomish County Cooperative Extension office is located in McCollum Park at
600 128th St SE, Everett, WA 98208.
Best wishes with your juniper!
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