Arbor Day expert advice courtesy of Total Landscape Care.
On Arbor Day, we like to show trees some serious love and one of the greatest favors you could do for these leafy giants is stop the practice of mulch volcanoes.
In recent years, these mounds of mulch have become as prevalent as the bubonic plague in 14th century Europe. Why individuals continue to believe that eight to 12 inches of mulch piled around a tree trunk is a good idea remains unclear, but the fact of the matter is they’ve sentenced the plant to a slow death.
“These issues have been on-going, but in recent years people have started to mound mulch up around the base of the trees – the ‘mulch volcano,’” said Martha Smith, a University of Illinois Extension horticulture educator. “New problems have emerged because of this practice. Tree bark is meant to protect the trunk. It works best in the air and light. If you pile mulch onto the bark, it is now exposed to dark and moisture. Bark will begin to rot, and rotted bark cannot protect the tree from insects and diseases. In fact, diseases grow better in this type of environment.
Mulch is by no means a bad idea. It has many beneficial qualities, but like everything else in life, it should be used in moderation.
When applied correctly it protects the tree from lawn mower or string trimmer damage, while keeping the soil moist and stabilizing the temperature in summer and winter. Organic mulches also eventually decompose and improve the soil structure.