What potential negative impact can high densities of sap well drilling have on vulnerable or young sap-producing trees?

The drilling can cause significant dieback in branches or even girdle the tree, leading to its death

While light tapping on a mature, healthy tree is usually negligible, intense foraging by sapsuckers presents a real danger to weaker or younger trees. When drilling activity is concentrated heavily on a single tree, the cumulative effect of numerous sap wells can become overwhelming. This consistent removal of vascular tissue beneath the bark can severely interrupt the flow of nutrients and water, leading to localized branch death (dieback). In severe cases, if the drilling completely encircles the trunk or branch, it effectively girdles the tree, cutting off vital circulation pathways and potentially resulting in the tree's death.