St Augustine - Chinch Bug

Oct 17 2002
Q: My sister has a problem with her St. Augustine grass. It is turning yellow for the first time in eleven years. The neighbor’s grass is turning yellow also. When pulling on the grass it seems to pull away from the roots. Can you tell us what is happening and how to save it?

A: St. Augustine grass is commonly attacked by chinch bugs, which feed at the base of the grass stems. One way to check for their presence is to mix up a gallon of water to which four tablespoons of lemon-scented dishwashing detergent has been added. Pour the mixture onto a small area at the edge of the yellow grass. Lay an old white towel over the spot and wait fifteen minutes. Chinch bugs, if present, will climb out of the grass and attach themselves to the towel in order to escape the soap. Adult chinch bugs are black with shiny white wing covers and are approximately 1/8 of an inch long. Nymphs are bright orange-red and somewhat smaller.

If you discover chinch bugs apply any insecticide containing carbaryl, permethrin or bifenthrin. Keep in mind that there could be other causes of yellow spots in St. Augustine grass. If you don't find any insects present, take a sample of the damaged grass to your local Extension office (1-800-ASKUGA-1))