Believe it or not there is no consensus concerning what to use to treat tree wounds. It is frequently decided that leaving nature take its course is best.

That "disclaimer" stated I can't resist the urge to actually use some plant safe labeled insecticide around open wounds. Having ants, termites, or anything else chewing in there hurts the tree.

In my heart I feel there must be a wood protecting/sealing agent which can be applied to open "dead" exposed wounds to keep rot out before the tree encapsulates it. Horticultural science must be near the point human medical science was in the 1700's. There is no widely accepted treatment.

Folks have all kinds of home remedies. My neighbor waits until the wood "feels dry" and applies undercoating of all things! Heck, it even seems to work for him, or at least hasn't killed his young tulip tree he ran his mower into not that I tried it.

Toronado3800-thank you for insight,suggestions. This is pretty much what I have read. Sorry this posted twice-see pic of my fav maple tree in other post "old injury..." above to see why she is so special. What color.