Good question Ms. Boekholder!
UNZ means Unzoned. Most of the available land in the Mat-Su Borough is Unzoned or Unrestricted. But, there are many smaller pieces, and some larger, that have protective Covenants, Codes and Restrictions. Sometimes, but not often, there are restrictions on the deeds. It really depends upon the specific piece of land you are considering.
So, if the description says, UNZ or Unrestricted and doesn't say CCR's, you can do just about anything you want with it. (Unless it is one of those rare pieces with Deed Restrictions.)
I would hope that the person who has listed the property can tell you more!