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Take-All Root Rot harmful to St. Augustine
Mississippi Gardens Newspaper and Web Column - July 19, 2004

One could argue about which turf grass to use in south Mississippi lawns. Some like Bermuda, others like Zoysia, some go for centipede, but I'm partial to St. Augustine grass. The others are just fine, but for a lush looking grass that feels great under bare feet, you can't beat St. Augustine. However, in many Mississippi landscapes, my favorite turf grass has contracted a deadly disease known as Take-All Root Rot.

Take-All is the reason why many homeowners have called their local Mississippi State University Extension Service Office looking for assistance in diagnosing problems in their St. Augustine grass lawns. In many cases this summer, Take All Root Rot has been a devastating culprit. Although it may also affect Bermuda, centipede and zoysia lawns, it seems that St. Augustine grass is hit more regularly.

The first symptoms of this fungal disease usually appear in the spring and summer as a yellowing of grass blades. At first glance, these symptoms could be mistaken as chinch bug damage, nutrient deficiencies or stress from waterlogged soils.

As time passes, the grass begins to thin out resulting in irregular patches a few feet in diameter that may eventually consume the entire lawn. When attacked, the St. Augustine may die entirely leaving bare ground or, there may be a patchwork of dead, declining and healthy turf. In many cases, the worst damage may occur in sunny locations.

Identifying grass with Take All Root Rot is easier than controlling it. Ordinarily, if you try to pull a St. Augustine runner (stolon) up from the soil it hangs on tightly. In fact, the runner will usually break before much is pulled loose. If Take All has set in, the runners can easily be lifted from the soil. There are also small, blackened areas on the runners that pathologists call "lesions". These are readily seen with the naked eye. If you have a magnifying lens and a little instruction, other characteristic symptoms can also be recognized.

Plant pathologists tell us that Take All is a stress related disease. Things like excessive rainfall, applying more nitrogen than necessary, low pH, improper mowing height, etc. may stress the grass leading to disease development. Therefore, following good management practices can help alleviate the danger of contracting Take All. Fungicides are available but their effectiveness is limited.

One way to find out how to control Take-All and take care of the lawn more effectively is to get a free copy of the Extension Service guide to growing turf grass entitled P1322 Establish and Manage the Home Lawn. A printed version is also available from your local County Extension Service Office.

Take-All Root Rot shouldn't keep us from enjoying St. Augustine lawns in south Mississippi. This beautiful turf grass may have its problems but its color and texture keep St. Augustine grass at the top of my list. Happy gardening!