By his calculations, you’d need to walk across your lawn roughly 125 times to get the aeration you’d need to reduce soil compaction effectively. A University of Arkansas professor did the math and found that if you use aerator shoes and take 40 steps per 10-foot-by-10-foot square of lawn, you’d only be aerating 0.04% of your lawn. Turf specialists recommend aerating 5% of your lawn to reduce compaction. If you’re looking to reduce compaction, the answer is, probably not. The bigger question is, are aerator shoes effective at aerating your lawn? That depends on what you mean by “work.” Aerator shoes will definitely make hundreds of tiny holes in your lawn, providing more nooks and crannies for grass seeds to sprout in if you’re planting or overseeding a lawn. A little air near the surface of the soil can also jump-start the microorganisms that break down thatch, the mass of old dead grass and organic matter that can build up on top of the soil. Roots can break through into new places, and more rain can find its way down into the soil. When you increase the amount of air in the soil, you increase the oxygen, water, and nutrients available to the grass. Without oxygen, your grass can’t absorb the water and nutrients your lawn needs for maximum growth extremely compacted soil can even form a solid barrier to grass roots. When the particles in your soil are compacted, and smushed too close together, there isn’t enough room around your grasses’ roots for air. There are two reasons people use aerator shoes: to reduce lawn compaction, and to make holes to help re-seeding. (If your soil is especially wet or sticky, you may strip off the top layer of soil when you lift your foot, too.) Your body weight drives the spikes into the lawn, creating little holes in the lawn when you lift your foot. To use aerator shoes, strap the soles onto your shoe, spikes down, and then walk around on your lawn.