
Light dormant pruning in late winter is all it wants, mostly thinning suckers if the customer wants a single-stem tree instead of a thicket. The trap is the opposite of what people expect: pawpaw is a shade-adapted understory species, so the damaging move is not pruning the pawpaw — it is opening the canopy above it, because a patch suddenly thrown into full sun after an overstory removal will scorch and sulk.
Individual stems dying back inside an established patch is normal turnover, not a dying tree — the colony keeps producing new suckers as older stems fade. Genuine decline is a whole patch thinning at once, and in central Indiana that almost always traces to something that changed the site: the overstory was cleared, the ground was graded, or the low wet ground the patch depended on got drained or filled.