Mulch volcanoes around trees kill more trees than drought

Piling mulch against a tree trunk (volcano mulching) holds moisture against the bark, causing rot, fungal infection, and root girdling. Per the ISA (International Society of Arboriculture), mulch should be 2-4 inches deep in a ring starting 3-6 inches away from the trunk. Every landscaping crew does it wrong because mounds look neat. This single practice kills more urban trees than any pest or disease.