Answer: I wouldn't recommend wrapping them with burlap, but here are a couple of ways to protect your new trees:
Winter injury can often be prevented by constructing a barrier of burlap or similar material on the south, southwest, and windward sides of evergreens. Or, surround the tree with a barrier, but leave the top open to allow for some air and light penetration.
A second way to reduce damage is to prop pine boughs or Christmas tree greens against or over evergreens to protect them from wind and sun and to catch more snow for natural protection.
I'd wait until just before a hard freeze to construct the barriers or to prop evergreen boughs.
Best wishes with your new trees.
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