Mulch can damage trees

Too much mulch applied over the root ball or resting against the trunk (see right photos) can cause problems for trees. Roots often grow up and into the mulch causing stem girdling roots which can kill trees (lower photo). In addition to causing problems, mulch can also hide decay and dead spots on the lower trunk and major roots. Decay in this portion of the tree can cause stability problems. Keep mulch about 12 to 18 inches from the trunk.

Mulch on root ball intercepts water, causes problems
Mulch close to trunk causes stem girdling root
Mulch close to trunk causes decline
Mulch close to trunk causes tree death
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