Flush Cuts
As you can see, in this oak sample, the bad sample had the cut made flush with the trunk. The good one left the branch collar without leaving a stub.
Note below the flush cut. The dying bark is the result of a flush cut and not so-called sun scold.
In this Black Walnut we see the results of a flush cut.
Note below the flush cut on the trunk.
Here in these dissections, you can see the internal response to flush cuts.