I found an old printed reference to a 1700 observation* that sometimes stem girdling would result in a swelling on the stem just above where the phloem was removed. In some cases, roots could then be grown from the swollen regions.

I am going to try this on a small limb of a maple tree that is going to be removed anyway. My thought is to girdle the limb and if it swells cut it off and treat it as a woody cutting. What is not clear from the old article is how much phloem to remove. All of it down to the xylem? All of it completely around the limb?

* Perhaps one Damuel du Monceau to whom I can find no online reference.