Lin, I wish I could you some advice, but I haven't a clue.
Surely someone with tree expertise will see this and respond.

Thanks, Carrie. I had sent a note to our Forestry agent, and here is his reply:

"The best I can tell from the photos is that heartwood is exposed at the site of the split. In an effort to save the tree, the torn limb should be removed, cutting carefully to minimize the size of the wound. Pruning paint should be applied to completely cover all exposed wood. There is no guarantee this will work since heartwood is exposed.

"Removal of the torn portion will leave the tree misshapen but it will be easier to manage compared to trying to tie the tree in such a manner as to attempt a natural rebinding of the wood at the site of the tear. Normally, with heartwood exposure it is only a matter of time and degree of exposure before the tree succumbs due to disease or insect invasion.

"If you decide to remove the tree and replant another Forest Pansy Redbud, you may want to prune co-dominant branches to build a strong central leader."

I am certainly not an expert but have had a lot of trees suffer from storm damage and I have always duck taped them (small trees or limbs) and 8 out of 10 have healed. Good luck

Thanks, butterflies. I would try that if there was a limb broken/split. This split wasn't to a limb but actually the trunk split in two. There was no way I could tape it up and hold the split together.

Based on what my Forestry guy said, I took off the half of the tree that split. I was fearful of the heartwood showing, so I left the part of the tear in place and pulled it together as much as I could with tie wraps. I'll paint the wound tomorrow with tree trunk goop and hope for the best.

On a good note, this is the perfect time of year to take softwood cuttings from redbuds - let's hope some of them start!