Identifying and Treating Red-Brown Spots in Your Lawn

Understanding Lawn Fungus After Wet Weather

After a prolonged wet period in Ohio, you may notice patches of dark red or brown spots spreading across your lawn. These symptoms often indicate a fungal disease, which thrives in moist, humid conditions and can expand rapidly if left untreated.

How to Confirm a Fungal Infection

Examine the grass blades closely. Fungal infections typically produce distinct lesions, discoloration, or a powdery residue on the foliage. For visual reference, consult the Texas A&M Plant Pathology Lab or the University of Nebraska Brown Patch Guide for images of common turf diseases.

Effective Treatment Steps

• Apply a fungicide: Local garden centers carry fungicidal products labeled for lawn use. Choose one containing active ingredients like maneb, zineb, or mancozeb, and apply at two-week intervals as needed.
• Sanitize equipment: Clean mowers and tools with a bleach solution to prevent spreading spores.
• Improve cultural practices: Ensure your lawn has well-draining, fertile soil, adequate sunlight, and 1–3 inches of water per week. Avoid overwatering, which encourages fungal growth.

When to Act

Fungal outbreaks can destroy large areas quickly. Begin treatment as soon as you suspect an infection. If you're unsure, consider submitting a sample to your local extension service for a precise diagnosis.

With prompt action and proper lawn care, you can restore a healthy, green lawn.