Figster:
Try smearing the splits with a soft, wax. Wax rings that are used to seal toilet bowls works great. The rings are cheap, and the wax -at room temps. - is soft and pliable. You will be able to scrape off some wax and with your warm fingers, smear those cracks full of wax, which will prevent water from re-entering the crack, getting under the bark, and then, when re-freezing, cause more splitting. Before sealing the cut with the softened wax, dust the open bark-split with powdered cinnamon....then, seal with wax. Tie the affected branches to the stake, and take the downwards pressure off them. The branches will sag when they are once again loaded with leaves. As the branches get thicker and stronger, the bark splits will heal over. Alternatively, you could tie the affected branches to the central main-stem, to prevent sagging, due to weight, ice, snow wind, etc. In other words....do what it takes to stop those branches from bending downwards.
By the way, I use this 'cinnamon and sealing wax' method to coat/protect all pruning cuts, and seal off the ends of cuttings used for rooting.
(Personally, I think the bark splits are the results from freezing/thawing cycles). They will eventually heal over as new cambium rolls into the bark cracks.
************************************************************************************************
GENERAL QUESTION TO FORUM MEMBERS:
HAS ANYONE EVER USED "WILT-PRUF" TO COAT BARE BRANCHES...TO HELP PREVENT DESICCATION AND BARK-SPLITS? I read that WILT-PRUF can be brushed onto the exposed branches, and mainstems, using a foam brush.
Would a coat of "white-wash" prevent these kind of bark-splits? My trees show some of the same damage from splitting bark....I'm thinking about either trying the whitewash, or "WILT-PRUF".
I would rather not have to deal with cracking bark if it could be prevented.
Frank