This has been discussed at our university quite a bit and I think the general concensus was an acreage number (which escapes me at the moment) not a portion of the property. Deer do not recognize property boundaries or owners. What you should be dealing with is an acreage number (not percentage) that can impact the deer herd positively. Percentage numbers are misleading and do not matter. 2% of a 100 acre parcel is 2 acres. 10% of a ten acre parcel is 1 acre. So obviously 10% is not better than 2% in this case. Do your own research and come up with an acreage number that makes sense and is (hopefully) proven by research to positively impact herd condition.