Iris Cohen schreef
I don't recall if I asked this question here. The great tree authority
Shigo, based on his experiments & studies, concluded that the best way to
treat a pruning wound is to leave it open to the air.

My bonsai teacher, based on his 40 years of experience, insists that Shigo
never grew a bonsai. He says you must cover pruning cuts on a bonsai to
promote rapid healing. any of you know anything about this?
Iris

+ + +
IIRC Shigo did not say that healing cannot be accelerated, just that this
(accelerating healing) is not beneficial in the long run.

Also, it may be correct that Shigo never grew anything.
PvR