Dirt to restore the grade away from the foundation was the right answer. A foundation wrap or spray would cause them to dig and restore the grade. The problem would be solved, what a coincidence!
Your place sounds like mine with the big trees and in-law basement, although I'm much closer to Dave's town.
I've been cleaning up a year's worth of leaves and cutting back the overgrown plants. It'll all be worth it when you look back after a year.