Not (always) so serious...
Among the most commonly found, easily identifiable, and least devastating diseases you will find Grey Leaf Spot. This fungus creates small circular grey legions on the leaf blades. It usually does not kill the plant, but it can hurt the aesthetics of your lawn. Once the disease has been controlled or has abated naturally, the turf typically rebounds in short order. The leaf tissue that has been damaged only needs to grow out long enough to be mowed off, and then the turf looks anew. Some instances of this pathogen are so mild that they may not even require a fungicide treatment. The plant will simply maintain its aesthetics adequately enough that no one will notice it, or the disease will simply run its course.
Figure 2. Grey Leaf Spot legions on a St. Augustine grass shoot. Photo courtesy of University of Florida IFAS Extension1
Grey Leaf Spot on Zoysia grass.
Serious, very serious...
Pathogens that affect (St. Augustine or Zoysia) grass root-systems can be both difficult to recognize and diagnose. Often the symptoms are blamed on another cause, and the symptoms are therefore neglected, resulting in loss of turf. In order to confirm a diagnosis with soil dwelling pathogens one would need lab work to verify the suspicion. The problem is that soil dwelling diseases of St. Augustine (and Zoysia grass) can be brutally devastating, and they can do so quickly. If you are not certain, the best thing you can do is to call a professional, preferably one with a formal education in turfgrass management.
We get lots of questions about mushrooms in St. Augustine grass lawns in Tampa. Suffice to say that in all instances but one they do not negatively impact turfgrass. Other fungi that dwell in the soil but do not affect turf may produce mushrooms as a normal part of thier life cycle. The one pathogen that produces mushrooms and can afflict turfgrass is known as Fairy Ring. Rarely do we see it in home lawns, and in most every case we know exactly what it is. Controlling it can be a very difficult matter. Look for the identifying ring of mushrooms seen below.
What You Should Do
Study the pictures included in this document and the list of symptoms below. If you see these types of things in your lawn, it might warrant further investigation. Sometimes university extension agents can be a good resource for diagnosing issues. You may need the help of a true turfgrass professional. Green Solutions Lawn Care & Pest Control is happy to provide free estimates for service if you suspect you need professional lawn care in the Tampa Bay area.
Look at this short list of symptoms that may point to a disease:
-- Green Solutions Lawn Care & Pest Control is an award-winning provider of lawn care and pest services in the Tampa Bay area. Our staff boasts two university educated turf agronomists and a university educated horticulturist. We offer fertilization, weed, insect and disease control programs for residential and commercial clients. We also offer general household pest control services. We have developed “GREEN” options for most of our services. We happily provide free estimates.
******** 813-684-7336 ********
1. These photos were taken from document PP204, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date March 2005. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.
2. This photo was taken from document SS-PLP-7, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date May 1991. Revised February 2011. Visit the EDIS website at http://edis.ifas.ufl.edu.