Aerators were originally designed for improving the air/soil interface of lawns and golf courses. In other countries they developed heavier units to aerate pastures that were compacted from grazing. They have had sporadic use here in the Northeast. There are two basic similar designs with differences in how the blade is designed and enters the soil. Most units have replaced the solid iron holding the shaft (picture at
right) with a heavy āCā shaped spring, to cushion the impacts with rocks.