A customer of mine has two mature maples that shade part of her lawn with the predictable result of poor turf growth underneath. Adding to the problem is that this area is on a slope and the soil is sandy, so what little water remains on the slope is slurped up by the maples. She'd like us to correct the problem and I'm thinking of stone under the maples perhaps with some ornamental grasses or hostas. Ordinarily I'd put down landscape fabric first, but these maples have some exposed roots and I'm wondering if covering them entirely would be detrimental to their health. They're in good shape, the lawn isn't. What do you think? Fabric - yes or no?