By MINDY POEHL | Central Texas Edition

Dr. Jim McAfee, Extension turf specialist, speaks about turfgrass management and different varieties of grass at a Sport Field/Turf Management Seminar in Waco. — Photo by Mindy Poehl

May 4, 2006 - Seventy percent of turfgrass in Texas is used in home landscapes. And, properly taking care of the grass and protecting it from parasites is important to maintaining a healthy lawn.

Turfgrass variety selection and maintenance was discussed at the Sports Field/Turf Management Seminar held in Waco on April 27. Dr. Jim McAfee, Extension turf specialist, said St. Augustine and bermudagrasses are found extensively throughout the state of Texas. St. Augustine is limited to warmer areas because it does not survive winter temperatures as well as bermudagrass, with its Northern area of adaptation stopping around the Fort Worth area. 

“Bermudagrass is the best warm season grass for shade problem areas,” McAfee said.   

Zoysiagrass is also planted in Texas. Buffalograss is found in the dryer areas where rainfall is limited to less than 20 inches annually. Centipede is adapted for use in Central and South Eastern areas of Texas, especially on sandy, well drained soils. Tall fescues are used in the Dallas/Fort Worth area and northern Texas, but generally will require irrigation to survive heat and drought, explained McAfee.  

Rolled turgrass awaits to be rolled onto lawns with a tractor. — Courtesy photo

Weeds are constant problem causers in grasses.

“Weeds take away from the overall balance of a turf and add to its maintenance requirements,” said McAfee. “Since weeds are aggressive and reproduce quickly, they are able to invade weak spots where turfgrasses are not growing.”

For fertilizing, McAfee stated, “Only apply what is needed.”

He suggested having a buffer zone of 16 feet from waterways and do not put any fertilizer on the grass if you know it will rain soon. The chemicals will leach into waterways.

“Make the first application of fertilizer after the turf begins to turn green in the spring,” McAfee said. “Make a second application approximately six weeks later. And use a balanced fertilizer with a slow release form of nitrogen.”

Do not apply fertilizer during the hot summer months. This will make the grass susceptible to drought stress and cause the plant to require additional watering. 

When watering, McAfee said to notice the environmental conditions around the turf. 

“Shaded areas do not require as much water as non-shaded areas,” McAfee said. “The roots of mature trees and shrubs need water, so you may have to water more in mature landscapes where the roots of many plants compete for water.”

If the soil is mainly clay, apply 1 to 1 1/2 inches of water to moisten the root zone to a 6-inch depth. Most sports fields are built out of sand, and sandy soil can be moistened to 6 inches by as little as 1/2 inch. 

 When mowing grasses, lower the mowing height by 1/3 the recommended mowing height in the spring. This will remove any excess thatch build up. 

“Continue using this mowing height throughout the spring. This practice will enhance the growth of dense turf,” McAfee said. “As the day time temperatures increase, the mowing height should be increased by 1/3 the recommended height. This will help to insulate the turf from the heat of summer as well as the cold of winter.”

During periods of active growth you should monitor your turf regularly for any signs of disease or insect problems. These can be simple problems to solve if detected early. 

Take-all root rot, a disease affecting St. Augustine lawns, can be controlled, although it's an expensive process, said Dr. Karl Steddom, Extension plant pathologist.

"But if they (homeowners) have root rot now, they have to treat it now –

right now – or wait until this fall," said Steddom.

With severe infestations, take-all symptoms include large areas of yellowing and dying leaves, dead roots and the loss of a large percentage of the stolons, or runners. Take-all is also known as bermudagrass decline.

During certain times of the year, the disease may be confused with the symptoms of chinch bug infestations or brown patch, explained Steddom.

“But brown patch only kills the leaves – not the roots and stolons – and chinch bugs don't become active until hot weather,” Steddom said. "So if homeowners have large yellowing or bare spots in their St. Augustine lawns now (late April), the chances are very good that it's take-all.”

Pull up some of the yellowing grass, and if the roots are dying, it's probably take-all, Steddom said. Dead grass roots will be dark brown or black. Heathy roots will be white.

First, forget using the prepackaged treatments for take-all found in home improvement stores and gardening centers, Steddom said. Only two of these "boxed" treatments are labeled for take-all and both contain the active ingredient myclobutanil. If applied when temperatures are above 80 F, the chemical can stunt lawns.

It is possible to buy effective treatments for late spring applications from agricultural chemical distributors. Neither product requires a pesticide applicator's license to purchase or use. One product is Heritage; the other, Bayleton.

Because they are packaged for professional applicators, it won't be possible to buy a small amount of either, he said. Cost of the products will range from about $100 to nearly $400. 

"The products need to get to the roots to work, so they should be applied with enough water to penetrate the soil 1-2 inches," Steddom said. "A garden hose sprayer or a small pump-up tank are not going to work."