The insistence of the landscape industry to over mulch trees boggles my mind. Mulch volcanoes run rampant in wealthy, NJ towns. Mounding mulch against the trunk of a tree, no matter how old or young the tree may be, will KILL the tree. Mulch in a doughnut shape around the tree, 3″ thick, keeping the mulch away from the base of the tree.
Want to learn more? Purchase a Volcanoes Killing Trees in NJ pamphlet from the NJ Shade Tree Federation.
Make copies and give it to your neighbors!