We have had a number of well established trees die this past year. After several years of drought we had an exceptionally wet winter. No hard freezing here. We have lost redwoods, poplar/cottonwoods, Italian cypress, willow, fig (black) and fig (white).All died seemingly spontaneously. The fig trees, now dead, are splitting open on the trunks and limbs.
Suddenly Dead Trees, Some Splitting Open
Certified GKH Gardening Expert
This is likely caused by the fluctuation in the environmental conditions you mention.
Wounds should not be covered; there is a technique called tracing, that is explained in the links below.
You can also check with your County Extension Office, they may have specific care to your region.
These trees are dead - past "tracing".
The cracks were not caused by freezing- as in "frost cracks" and it is the trunks, so not "bark splitting" either.