
Green hulls the size of tennis balls drop from height between September and November, dent car hoods, roll underfoot on drives and walks, and rot into black slime on concrete. The hulls stain concrete, decking, and hands more or less permanently, and squirrels cache them across the entire property, which is why homeowners describe the mess as bigger than the tree.
Roughly 50 to 75 ft tall with a 30 to 50 ft spread at maturity, making it a large tree but rarely the tallest on a lot, and generally a mid-to-upper cost bracket removal. Straight-stemmed yard walnuts can carry real sawlog value, so it is worth asking whether the homeowner wants the log sold or milled before the trunk gets bucked into 16-inch rounds.