Mulch your tree twice per year. Spread mulch (undyed woodchips and/or leaves/compost) in a circle around your tree, as far out as you are willing. The bigger the circle, the better for the tree. Ensure that the mulch is not more than two to four inches deep, so that roots can still get oxygen. Keep mulch in a “doughnut” shape, leaving about six inches of space around the trunk.
Tip: Never pile mulch in a “volcano” shape around the trunk as this holds moisture and causes decay.