The best way to get the most out of both treatments at the same time is to combine core aeration and overseeding. Overseeding a lawn after it has been aerated produces an open channel for seed to penetrate the soil and promotes optimal seed and soil connection. Since the removed cores helped to reduce soil compaction and thatch development, the new seed may emerge and develop itself much faster. The capacity to absorb oxygen and water is also enhanced, allowing for the development of new, strong roots and nutrient-rich soil. With a combined aeration and overseeding treatment, you'll get optimum results from both treatments by emphasizing seed-to-soil contact, providing your grass the best chance of becoming lush, robust, and healthy before the winter season.