Answer: The mushrooms are growing in an area that contains decomposing organic matter. This could be from potting soil, bark mulch, or even dead tree roots. The mushrooms themselves won't hurt your crape myrtle. You can simply pick them one by one or rake them out and dispose of them. New mushrooms may grow again - until the decomposing organic matter is either removed or it completely decomposes. As long as your crape myrtle looks healthy, there's nothing to worry about.
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