Bob Weinberger wrote:

"kate" wrote in message ...

The problem from Black Walnut is not from the roots, but from the alliopathic compound (Juglans
IIRC) that is contained in the leaves and the hulls of the nuts. This compound leaches out into the
soil and prevents other plants from germinating or from growing well (or at all). Any other plants
that are much beyond the drip line of the Black Walnut trees should have no problem.

Thanks - Juglone was the culprit mentioned, but the first mention was
the roots, as well as the leaves and hulls.Is it safe to assume that the
roots wouldn't extend further than the drip line?

Kate