Last year I planted a little Garfield Plantation sour cherry tree a little too close to the road. It probably would have been just fine in any other winter but there was too much snow in 2011, plowed up and over our driveway, down the hill and over the little tree.
I’ve been researching possible repairs since the snow melted enough to expose the break. Finally I came across a reference book at a local library (crumbling tissue paper pages smeared with dirty fingerprints, the spine folded almost in half) with instructions for splinting a young tree. As long as there is still a strip of green cambium (the inner, living layer of bark that transmits nutrients and water up the trunk), this should work.
First, splint the trunk with a thin, flexible piece of wood or metal. I happened to have a scrap piece of ebony down cellar that would do. Thanks John and Ruth! Place the splint on the opposite side of the trunk from the intact layer and tie it in place at the top and bottom. Form a layer of clean melted beeswax around the break. (I melted about an oz of beeswax in a piece of foi, over a double boiler. It hardened into a paste on the way out to the tree – perfect.) Dip a strip of muslin in the wax and wrap the trunk, avoiding buds.