A Bluebird aerator is seen here at an outdoor power equipment rental company. This type of walk-behind aerator is unwieldy at slow speeds and will operate with less ?EUR??,,????'??kick?EUR??,,????'?? at a higher power setting. This aerator can be used by a single operator to handle small and medium – sized turf sites.

Cultivation has a different meaning in the turf industry that in traditional agriculture. In agriculture, the term refers to the tilling of the soil; a practice that is not possible on mature turf.

In the turf industry, cultivation refers to a number of mechanical processes that are used to loosen the soil and reduce compaction, to reduce thatch, or to groom the surface.

These soil plugs show healthy turf without an excessive layer of thatch build-up. Superintendents should check aeration cores from all corners of a turfgrass area to compare thatch buildup and soil profiles.

Core Aerification

This is one of the most effective cultivation practices in reducing thatch and compaction. Hollow metal tines or open spoons are used to remove a core of soil from the turf. Hollow tines are generally operated in a vertical manner, or they are mounted on a rolling drum. The vertical tine method is more effective than using open spoons and is often used on high-maintenance areas such as golf courses and lawns.

Tractor-drawn, spoon-type aerifiers are capable of covering large areas quickly and are most often used on fairways, sports fields and other large turf areas. Removing the core helps to loosen the soil in the vicinity of the core and improve root growth of the grass plant. It is common to find that core holes have filled in with roots in the weeks following aerification.

Thatch Control

Excessive thatch can cause a multitude of problems. It can keep the crowns of the grass from the soil, leaving it more vulnerable to damage caused by rapid changes in air temperature that would otherwise be buffered by the near constant temperature of the soil. Elevated crowns can also lead to scalping if excess tissue is removed during mowing.

Aeration is an effective way to reduce thatch. Core aeration opens the thatch layer and allows moisture and oxygen to penetrate the ground, which increases microbial activity that helps break down the thatch.

Aerating machines like this model by John Deere remove plugs of soil or simply open holes in the turf without removing soil, which aids in turf rooting and thatch breakdown. Aerating also helps loosen bare spots in the soil to prepare for seeding.

Aerate With Care

Although it can be very helpful in maintaining a healthy lawn, there are some precautions to take in order to avoid causing problems through aeration. The time of year that aerating is done is important. Core aerification during the spring can bring up weed seeds. Avoid times that encourage weed establishment. High-temperature during the summer increases stress, so avoid aerating during midsummer. Fall is a good time to aerate. The soil is moist and the cores will be removed intact and can be left on the lawn where they will gradually disintegrate. Make sure to keep the turf watered following aerification as it is more susceptible to drying.

Tines

• Solid tines?EUR??,,????'??+ These tines penetrate the soil and open a hole, but do not remove a soil plug. They are less disruptive to the turf surface, allowing it to recover faster. However, they are not as effective at loosening the soil as core aerification. Standard tines are between .25 to 1-inch in diameter and penetrate to a depth of approximately 3 inches.
• Hollow tines?EUR??,,????'??+ These tines remove a soil plug from the turf and are effective in reducing soil compaction and allowing for maximum penetration of multiple topdressing layers. However, they can cause damage in turf that is not well-rooted as they may actually pull up the sod.

Source: Fundamentals of Turfgrass Management, second edition, Nick Christians