I have never been able to hunt on private land. At the same time, in 10 years working with the Forest Service I have to say that a lot of the private land issues with people disrespecting the land and property also apply on public lands that are owned by all of us. I've seen allotment fences cut so someone could drive their atv offroad, which meant that cattle were allowed to destroy wet meadows and recovering aspen stands. I've seen piles of trash. I've seen where people have cut firewood inside riparian areas, daylighting slow pools (which can raise water temperatures and harm trout) and eliminating nesting habitats, when there was plenty of wood to be cut elsewhere that wouldn't have damaged the habitat. I often talk with ranchers, hunters, campers, loggers, and managers; even if they don't always agree on the how, they tend to want a balance between maintaining the habitat and still using the land, especially the oldtimers who have spent much of their lives on the land. Having talked to hydrologists, biologists, soil scientists, timber specialists, etc, it seems like the most sure fire way to have recreation shut down in an area is when people don't respect it, and it only takes a few idiots to ruin it for everyone. I've seen the frustration when years were spent restoring a meadow so that the aspen on the edges had enough water only to have it all ruined when someone drove their truck right through the middle of it, causing the water to drain away before it could water the aspen stand.
I can also say that the people working to manage those lands really appreciate any help they can get, though they are still stuck with the bureaucratic hoops they have to jump through. Groups that take the time to partner with them on restoration projects can and do make a big difference. I often hear good things about RMEF, Duck Unlimited, Trout Unlimited, etc. If we as hunters and outdoorsmen want to keep these lands open for our kids and grandkids to enjoy, these groups are a great place to start. We also need to do a better job educating the other groups out there about the value that these lands hold, especially the values that aren't as "obvious" as timber harvest and energy exploration. To that end we may need to cultivate relationships with groups of other users, like hikers, mountain bikers, and the like, find ways to educate them, and then advocate for public land access and habitat conservation as a combined group. I get the feeling that most people these days do not understand the value that habitat and wildlife really has, or how that value affects them even if they don't use our public lands.