Fungal Challenges for Lawn and Turf
Dollar Spot, Brown Patch, and Antifungal Products for Golf Courses and Turf
Microbes inhabit every niche in of our natural landscape: without them there would be no natural landscape.
But in certain circumstances specific fungi can cause problems that are both cosmetic and costly.
Notable for lawn and turf applications are the fungal blights known as Dollar Spot, Brown Patch (Foliar Blight), or Snow Mold.
These common names are for turf pathogens that result because of specific fungi that exist in the natural environment; whose spores are ever present and waiting for the proper environmental conditions to germinate and grow in the grass.
For most home owners, these issues can be small and annoying. However, for a golf course these fungi can cost millions of dollars in prevention, damage and remediation annually.
The names associated with the disease are not caused by single fungi, but are better understood to be the ‘appearance’ a specific type of fungal attaché (roots vs. leaf) and that different fungi can cause what appears to be the same disease (pathology).
This is important because treating grass and turf for a given disorder may or may not be effective due to the type of fungi actually causing the disease. Specific fungi that cause these fungal turf blights are:
Dollar Spot: Pythium aphanidermatum and Sclerotinia homoeocarpa
Brown Patch or Anthracnose: Colletotrichum graminicola or Septoria glycines
Snow Mold: Microdochium nivale.
Although these fungi may be exotic sounding, they are very common fungi common found in cereal crops and wild grasses.
Like most microbiological challenges, the existence of a problem microorganism (fungi in this case) is constant.
What has changed is our use of a particular product, such as genetically homogenous grass types. This allows for these specific fungi to cause considerable damage in a short period of time.
Balance is the key to minimizing fungal growth on grass.
Defending against these fungi typically relies on:
1. Reducing the stress on the turf.
2. Balancing the factors that cause stress with the local environment.
3. Enhancing the factors that dis-favor growth of the fungi.
Helping the plant maintain a low stress (adequate water, nutrients, aeration, and root density, etc.,) will help reduce the susceptibility to the fungi.
Balancing the variables that dis-favor a given fungi will also work to the plants advantage (moisture content, root density, turf seed homogeneity, nutrient levels, etc.).
The challenge in balancing these factors is in achieving a continuum that needs constant observation and monitoring so that the use of antifungal strategies can be incorporated.
The use of fungicides is not a simple matter of spraying and walking away. Best results are when:
1. The identity of the target fungi is known.
2. Application rate of the fungicide is balanced.
3. Applying the fungicide does NOT add to the stress of the turf.
4. The other factors have already been managed to lower the overall stress of the turf.
Our recommendation is to first identify which microorganisms are present. Once you know the cause of the disorder, a strategy can be developed to identify which fungicidal product provides the best results with the least amount of cost and maintenance.
In Situ testing is an excellent way to determine the efficacy of the products used to treat turf blight. With an average cost of maintaining each fairway easily running into six figures, setting up the right conditions (temperature, humidity, light exposure, drainage, soils and grass types) in a lab can reduce the need to experiment on site.
For more information about fungal product tests and golf turf test services, drop us a note at firstname.lastname@example.org or call the lab at 847-677-4575.
Situ Biosciences antifungal tests use USDA permitted fungi including C. graminicola, P. aphanidermatum and S. glycines.