Question
To solve a drainage issue, and add a pleasant country cottage sort of feature to the yard, I am planning a dry creek bed terminating in a rain garden.  Both features will be dry most of the time, primarily getting some standing water after especially heavy rains (about once or twice per year).  Next to the site of the proposed rain garden is a large red maple tree which is surrounded by an old dilapidated raised bed.  I plan to remove the old wooden walls but leave the soil levels as is.  Of course the tree's roots extend well beyond the raised bed so I am a little concerned about having part-time standing water over the roots.  The rain garden will cover about 1/4 the circumference of the tree's roots.  It will be about 4 to 5 feet wide starting 6 feet from the trunk.  Could this harm the tree?

Answer
If its really a red maple, I seriously doubt if this would harm the tree. Red Maples are naturally found in woods along creek banks and often seek wet locations. As long as it is not covered in water for long periods of time..like weeks not days or hours.
Good Luck
Sean J Murphy, LA,ISA, LEED AP
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