Burlap wrapping arbervites
The burlap doesn't need to be wrapped tightly, just secure enough that it doesn't sag or pull away in heavy snow or wind. Leave the top open.
Although the photos show brown inner needles, the outer needles appear to be healthy. Arborvitae shed some needles closest to the trunk in the fall so what's shown may be normal. Fall needle browning will probably be less conspicuous after the trees are well established. In any case the brown needles are dead and will not become green again.
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