Much has been written about the serious decline of our forest habitats as a result of overbrowsing by deer. An excellent overview can be found in the Proceedings of the State of the Forest Symposium http://www.njaudubon.org/Conservation/ForestSym.html held October 3, 2002 and jointly sponsored by The Nature Conservancy, New Jersey Audubon Society, and New Jersey Conservation Foundation. What needs to be added to that general overview is a sense of urgency added by the real possibility that our mature trees could be attacked by one or more of the emerging threats, Sudden Oak Death, Asian Longhorned Beetle, Emerald Ash Borer and Bacterial Leaf Scorch, to cite just a few. Under normal conditions, we might have a younger, more robust generation of trees to replace them. But, of course, we do not since the seedlings have been eliminated along with the rest of the understory by deer browse.
The Rutgers University NJ Agricultural Experiment Station web site has information about NJ specific deer matters.