Grafting a forest

I'm a farmer in west Michigan 5b.
Our biggest product is woodland pastured pork.

I'd like to increase the percentage of food they get from the forest. Observing has led me to conclude that my forest grows oaks well; and the pigs eat the acorns, preferring them over my grain mixes. So now I see improved acorn bearing oak types. If I can go into an oak sapling in the wood edge (already above the damage line from pigs) and graft from one of these, and get a 5 year headstart on the process, that would be cool. Same for improved sugar maples some of the pippins on the farm.

Does this work, to go into the woods and graft onto existing trees?

Any local people with experience?

Thanks,
Luke

I'm not local, and don't know a thing about grafting oaks, but if a species will accept grafting, there's not any broadly applicable reason you couldn't do graft onto an existing tree in the forest. Methods may vary compared to a nursery situation where you are better able to match scion/rootstock sizes, but this isn't a factor for all types of grafting...

Since you're talking about grafting above the pig damage line, there will be a significant amount of trunk below the graft; in fruit trees, this could be a problem as it might send up alternate trunks that wouldn't have the desired characteristics. On the other hand, maybe the pigs would chomp any such problems in the bud for you...

I found this little .pdf discussing hardwood grafting of several species, including some oaks, as part of the Tennessee Valley Authority's hardwood forest tree improvement program: http://www.rngr.net/publications/tpn/17-2/pdf.2005-05-11.3026582706/