I agree, I would check for voles. Where I work we have the same problem and if you peer at the thicker stems under the foliage you should be able to see where the bark has been chewed off. If there's no sign of chewing then one should look for another cause but definitely check that out first.
If the brown and green parts are the same juniper (or whatever it is) cultivar/species then I would expect normal winter colour change (to more brownish) would affect all the plant, unless the green part had been more protected somehow (such as by snow cover, which I assume is doubtful where KGL is located).
