xeriscaping with mature trees

We're in zone 6a, and I want to convert our suburban front and back lawns to xeriscape. We have a large ash tree in the front (gets treatment for emerald ash borer) and four trees line the back. The back trees are against the fence, and we have a shallow yard, maybe 15 feet from the patio to the fence. Are there solutions that match the watering needs of the trees? (Ash, maple, sterile apple, crabapple.) I wanted meadow plants, but their water needs are less frequent. What plants take less frequent, deep watering?