Have you ever noticed that the grass is always greener - no, not over the septic tank - around a mole hill that has been knocked down? A mole is, in a way, a giant aerator, which is simply a device that pokes holes in your lawn.  Aeration benefits your lawn in several ways:

• It allows oxygen, water, and nutrients to penetrate farther into the soil, encouraging deeper root growth.
• It reduces soil compaction.
• If a coring aerator is used, it helps reduce thatch by bringing soil to the surface which then lays on top of the thatch, breaking it down naturally.
• All of these effects will contribute to a healthier and more vigorous lawn. A power aerator is the fastest and most efficient way to aerate your lawn. Slightly overlap each pass until the entire lawn has been aerated.
• Hollow tining lifts out small cores of grass and soil. This creates large air pockets in the lawn. Top dressing may be applied after hollow tining to improve soil structure and help further in thatch control.
• After you finish aerating your lawn, any cores left lying on the grass can be taken care of easily. Drag a piece of chain-link fencing around your lawn behind a mower or by hand. The fencing will break up the cores into very small pieces. Another approach is to simply set the blade on your mower a little lower than normal, then mow over the cores.