Take-All Patch is Acting Up!
Take-all patch is a serious turf disease caused by the soilborne fungus Gaeumannomyces graminis. It primarily affects creeping bentgrass on fairways, tees, and putting greens and produces sunken, discolored patches which are often yellow to brown and crescent- or ring-shaped (see recent photos from local golf course fairways). Over the last two weeks, frequent rainfall and cool nighttime temperatures have created ideal conditions for the disease to thrive. Below are key identification signs and management guidelines to help control outbreaks.
What to Watch For
- Patches range from a few inches to several feet wide.
- Affected grass wilts and dies due to root and stolon damage.
- Most active from April through October, especially April–July.
What Causes It?
- Soil temperatures (over 55°F)
- Soil pH above 6.0
- Poor drainage, soil compaction, and saturated conditions
Prevention & Management tips
- Maintain soil pH between 5.5–6.0
- Apply ammonium-based fertilizers in spring and fall
- Avoid lime and nitrate-based fertilizers
- Reduce thatch, improve drainage and aerate compacted soil
- Water deeply but infrequently
- For manganese-deficient soils, apply up to 6 lbs/acre of manganese sulfate. Use high-volume sprays to get the nutrient into the root zone.
Fungicide Application Guidelines
- Best Timing:
- Preventive: Apply from mid-September to early November when 2-inch soil temps are 45–60°F (7–16°C).
- High Disease Pressure: Begin in early April, with a 21–28 day interval.
- Spring Symptoms: Treat when 2-inch soil temps average above 55°F (13°C).
- Summer Worsening: Use spring and early-summer applications to support recovery.
- Fungicide Use:
- Use systemic fungicides (e.g., DMI, QoI, or DMI/QoI mixtures).
- Rotate FRAC classes to manage resistance.
- Apply high labeled rates for most effective control.
- Target infected areas with applications.
- Apply with ≥5 gal water/1,000 sq ft or irrigate lightly after application to help move products into the root zone.
Submitted by: Dr. Geunhwa Jung, with Ela Jain, Undergraduate Student, Stockbridge School of Agriculture