
This is a removal-first species and one of the few on this list that genuinely earns it. A mature black locust in a yard is usually hollow or getting there — locust borer larvae tunnel the trunk and open it to Phellinus robiniae heart rot, so the crown stays green while the stem quietly loses the section holding it up.
Medium tree · On the hazard list · $250–$1,400 typical
Also searched as locust, yellow locust, false acacia, common locust.