Chewin' The Cud:

  The Cahaba Tractor Corner 
 
        Aerating Your Lawn or Pasture
         for Maximum Moisture Benefit
                 in Times of Drought
 

As of July 2011, The National Weather Service Drought Monitor indicates that abnormally to exceptional drought conditions persist in the state of Alabama. With the looming threat of continued drought throughout the summer, there are steps you can take now to help protect your lawn or pasture.

Aeration is one of the most important procedures in maintaining a beautiful and healthy lawn. Core aeration is a mechanical process which removes small plugs of soil and thatch from the lawn. It prevents soils from becoming overly compact and helps break up excessive thatch allowing vital nutrients, water, and oxygen to penetrate the soil and access the root zone. Loose soil allows the roots to grow a deeper, healthier root system. Deep digging roots tolerate stress and drought better than shallow roots making the lawn more disease resistant. If you do not aerate your lawn's soil, the grass roots will tend to weave themselves into each other instead of growing downward into the soil.

When should lawns be aerated?
Due to the high clay content in Alabama soils, aeration should be performed at least once per year. It is best to aerate warm season turf grasses such as Zoysia and Bermuda in mid-spring to summer. Avoid aerating when warm season grasses are dormant. This may encourage cool season weed competition. In addition, avoid aerating warm season grasses during spring green up. Warm season lawns should not be aerated until they have received their first mowing in spring.

Although aeration is beneficial for lawns, it also can open up spaces for weeds such as crabgrass to invade the lawn. It is best to aerate before you apply pre-emergence herbicides, rather than after. Aerating after herbicide application can reduce the chemical barrier formed by the herbicide, thereby allowing some weeds to germinate and grow into the lawn. Follow up with a fertilizer to help the lawn compete against weeds. Be sure the lawn receives adequate moisture following aeration, particularly where drought and high temperatures are common.

What can you expect?
Immediately after aeration, the lawn will be dotted with small plugs pulled from the soil. Within a week or two, these plugs of thatch and soil break apart and disappear into the lawn.

The aerification holes will be filled with white, actively growing roots in about seven to ten days. These roots are a sign that the turf grass is responding to the additional oxygen, moisture and nutrients in the soil from the aeration process.

Compacted soils and lawns with slopes will show a marked improvement in water puddling and runoff. Manual watering time should decrease due to better soil absorption. With repeat aerations over time, the lawn will show enhanced heat and drought stress tolerance.

Don't expect miracles from a single aeration, particularly on lawns growing on extremely poor soils. Most lawns benefit from a minimum of one aeration per year. Lawns that receive this care will be healthier, more vigorous, easier to maintain and have fewer problems than lawns that are neglected.

Equipment Affects the Outcome
The type of aeration equipment can determine how effective the treatment will be. In general, turf responds best when core holes are close and deep. Equipment with hollow tines removes soil cores. Equipment with open tines divots the soil surface. Aeration equipment also varies in tine size up to 3/4 inch diameter and in depth of penetration up to 4 inches, depending on the manufacturer's specifications.

Cahaba Tractor sells several implements to help with your lawn aeration. Speak with one of our staff to help determine which implement is right for you and your lawn or pasture.

Technical credit: Dr. Robert Shearman, turfgrass professor, University of Nebraska.