eddiee,
50 acres is small, yet enough to make a difference. You are not going to be able to let individual bucks walk for 3 or 4 years with realistic expectations of harvesting them as mature deer, unless... you border a protected area, or have a co-op formed with other land owners.
If you do not have these things going for you, you need to take a realistic assessment of your goals. We have 160 acres, and we consider it too small for serious management. Our goals are to harvest 2-1/2 yr old bucks and the ocassional 3-1/2 yr old. Our long term goal is to get cooperation from our neighbors - then up the bar, and although slow going, some of them are coming around. Leading by example has been our best course of persuation. Remember that a co-op does not neccessarily have to be of tracts of land that are continuous. In fact, a patchwork of QDM properties can "lift up" the quality of the entire area's entire herd. Smart neighbors notice the changes and may well sign on.
With 50 acres, you can attract the better bucks and does from the surrounding properties. A 10 acre sanctuary is helpful, but will not gaurantee success. When we started seriously, 5 years ago, our goal was to make our property "the best possible habitat and food source in the area" and we are seeing the results now. With that kind of goal, and reasonable expectations, you will not be discouraged, hunting should be fun, not frustrating - keep that in mind.
PS - I'm sure you are aware of the changes in NY's hunting seasons and harvest goals this year. If not, check out my post on the NORTHEAST section. I still think that this is the beginning of major changes in NY over the next 10 years, similar to what PA and other states are doing now. If landowners like yourself, start to make the transition now towards QDM like strategies, you will be ahead of the game, and so will your neighbors when these changes become law down the road. - Just my 2 cents.