Travis wrote:

I wouldn't plant anything within the drip line. If the Oaks are native
they will get enough water from the sky but if you plant anything under
them you will need to water and that might be too much for the Oaks.

No one in Pennsylvania waters oak trees and everyone has something
planted underneath. Oaks are a favorite shade tree for rhododendrons
and azaleas. If people didn't plant under oaks, there would not be many
rhododendron and azalea gardens left. Most parks have grass doing quite
well under oaks. So, I think it depends upon what is planted under the
oaks.
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