I reseeded a ring-shaped dead spot (the result of a glyphosate test last fall). The left side was tilled up by hand to a depth of about one inch. The right side had no soil preparation, but was seeded with triple the usual amount of seed. I Used Earth Services Shady Supreme. The site had light shade and was not irrigated. The test began on July 28--when rain was predicted. Rain was almost zero and was followed by 3 weeks of dryness. After 28 days which finally included a good rain, the tilled area had thin new grass. The heavy (triple) seed area had fair new grass result. Perhaps extra seed can compensate for limited or no soil preparation.