Man. Thats a heck of a problem over 20-30 years. Few grand every winter. Probably could have built one heck of a deer fence with those funds. I know I dont let recurring problems drain my wallet on an annual basis. You fix them. At one crazy time I believe GNF even cost shared....crazy!
Not every year for sure, only a couple of years that they ruined much hay. (and now that we have net wrap it is not so much of a problem)
Trees, now those are hard to get growing with 400 deer wandering thru browsing. We do replace quite a few trees each year. And the fence, doesn;t really cost much to fix but the insurance company doesn;t like the bill when your cows get out in the neighbors field cause a moose ran thru the fence instead of jumping it.
But since you bring up hay yards, I will ask you the same question I asked the geniuses from the G&F. If you get a puncture wound that pokes a hole in your liver, do you go get the problem fixed or just put a bandaid over the small hole to stop the bleeding on the outside?
Stick with me here ND, so I put up a hay fence like you and the G&F suggest , you do know I have to take the hay out of that fence to feed it to my cattle right? One year we put straw bales all around all our good alfalfa hay so the deer could not get at it in the stacks. That year we had a lot of snow and over 500 deer in the yard. When we took out those bales to feed them to the cattle, the deer would stand there waiting for the tractor to move and then eat while we fed the bales before we could get the straw bales moved back in place.
But here is the interesting part, remember how the genius fellas behind the baiting band were all in an up roar over "nose to nose" contact spreading disease? When we would feed these alfalfa bales and corn silage to the cattle, the deer would comingle and eat right across from the cows out of the same bunks. That year I found 3 sheds right in the feed bunks.
The G&F fellas really didn;t have an answer for that one, I wonder, do you Mr longshot?