Bermudagrass, a popular choice for lawns, sports fields, and golf courses due to its durability and resilience, is not immune to the threat of fungal diseases. Understanding what causes fungus in Bermudagrass, identifying the most prevalent types, and knowing the best treatment options are essential for maintaining a healthy and vibrant lawn.

Causes of Fungus in Bermudagrass

Fungal diseases in Bermudagrass can be triggered by a variety of factors, but the primary culprits include excessive moisture, poor air circulation, and compacted soil. Overwatering, high humidity, and dense thatch provide ideal conditions for fungi to thrive. Stress factors such as improper mowing, nutrient imbalance, and extreme temperatures also predispose Bermudagrass to fungal infections.

Most Common Fungal Diseases in Bermudagrass

  1. Brown Patch: This is characterized by circular patches of brown, dead grass. It typically occurs in warm, humid weather.
  2. Dollar Spot: Recognizable by small, silver-dollar-sized spots that can coalesce into larger patches, this fungus favors moist conditions and nutrient-deficient grass.
  3. Spring Dead Spot: This appears as circular patches of dead grass in spring, stemming from fungal infection the previous autumn.
  4. Leaf Spot: Starts as small, dark spots on grass blades that expand into larger lesions, often brown or purple. Severe infections can lead to “melting out”, severely thinning the turf. This fungus thrives in wet conditions and fluctuating temperatures.
  5. Pythium Blight: Known for creating greasy-looking, water-soaked spots that quickly turn into slimy masses under wet conditions. Often occurs during hot, humid nights and can spread rapidly across low-lying areas of a lawn.
  6. Fairy Ring: Manifests as dark green circles or arcs of grass, sometimes accompanied by mushrooms. The rings can expand outward as the fungus consumes organic matter in the soil, leaving the interior grass potentially dead and brown.
  7. Take-All Root Rot: Characterized by thinning patches of grass that may appear yellow or light green, this disease primarily affects the roots, leading to weakened, easy-to-pull turf. It is more prevalent in acidic soils and moist conditions.
  8. Grey Leaf Spot: This presents as small, oval, grey spots on the leaves that expand and kill large areas of the blade, particularly under conditions of high humidity and temperature. It can severely damage young, actively growing grass.

Best Treatment Options

Preventative Measures:

  • Proper Watering: Water deeply but infrequently to prevent moisture buildup on the surface, which fosters fungal growth.
  • Aeration: Regularly aerating the lawn helps improve drainage and reduces soil compaction.
  • Balanced Fertilization: Over or under-fertilizing can increase susceptibility to fungal diseases. Use a balanced fertilizer according to soil test recommendations.

Application Timing:

  • Preventative Fungicides: Apply during periods of high risk, such as in the spring or fall when temperatures and moisture levels promote fungal growth.
  • Corrective Treatment: If symptoms are observed, apply fungicides promptly to prevent further spread.

Corrective Measures:

  • Fungicidal Treatment: For active infections, fungicides that contain active ingredients like azoxystrobin, propiconazole, or pyraclostrobin are effective. Follow label instructions closely for the best results.

Best Fungicides for Bermudagrass

Choosing the right fungicide depends on the specific fungus and the extent of the infection. Here are some top recommendations:


Excellent for a wide range of fungal diseases, including Brown Patch and Dollar Spot.


Effective for controlling Brown Patch and Spring Dead Spot.


Works well against Dollar Spot and is also used for its preventive properties.

In conclusion, managing fungus in Bermudagrass involves a combination of cultural practices and the strategic use of fungicides. By understanding the environmental conditions that favor fungal growth and implementing effective preventive and corrective measures, you can maintain a healthy, lush Bermudagrass lawn.






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