"The most common mistake made in planting trees is covering the root flare ? where the trunk transitions laterally into root tissue ? with soil. If a tree trunk looks like a telephone pole stuck in the ground, the tree probably has been planted too deeply. If the flare is covered with dirt or mulch, the tree can suffer or die."

"The treatment: Remove the soil or mulch covering the flare. Many arborists use a compressed-air tool to blast away the soil without hurting the roots. This is usually an expensive undertaking, but so is replacing a large tree. You can dig yourself, but don't damage the roots."

"Uncovering the root flare ensures that the trunk's bark is not covered with any material that can keep it damp, causing rot."

"Pull up grass that covers the flare and add mulch in a
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