Red Thread
Does your lawn have what looks like dying patches with pink or reddish fibers in them? If so, You could have red thread, a turfgrass disease commonly caused by weather or environmental stress.
Don’t panic! This fungus can be treated and your grass can bounce back.
What Grasses Are Susceptible to Red Thread?
Typically, cool-season grasses are most susceptible to red thread. On the other hand, warm-season grasses are more resistant. Common vulnerable varieties include red fescue, ryegrass, Kentucky bluegrass, and bentgrass.
Red thread is common in Maryland, Virginia, and other East Coast states. It can occur in different climates, but it is more common in areas with high rainfall or high humidity in the late spring to summer. Primary climate conditions that can favor the development of red thread include:
- Low levels of nitrogen or inadequate fertilization
- Temperatures between 68 and 75 degrees Fahrenheit
- High humidity
- Low light levels
- Excessive travel over the grass
How Do I Identify It?
Red thread is a growth of the Laetisaria fuciformis fungus. It appears as red thread-like branches called sclerotia. These growths look similar to antlers. Beneath the red thread growths, your grass is tan or light brown.
Red thread is commonly confused with a disease called pink patch. Although the two conditions begin with different fungi, the way they manifest is similar. That’s why it’s important to get an expert opinion to diagnose your lawn if you believe you have red thread or pink patch.
Does Red Thread Kill Grass?
Although areas affected by red thread have grass that appears dead, red thread doesn’t actually kill grass.
The fungus that infects the turf lives in the thatch and soil and can be spread by dead infected plant material, mowing, or other mechanical maintenance. The pink growths that appear in the grass don’t actually infect the plant’s crown or roots, so your grass won’t be killed.
How Is Red Thread Treated?
The key to treating red thread in your lawn is to stop the fungus from growing.
Treatment begins by ensuring that your lawn is fertilized with the proper amount of nitrogen. Nitrogen applied to the lawn in the fall will nourish re-emerging turf in the spring. In turn, this will help prevent growth of the fungus that causes red thread.
It may take two years or more of proper fertilization to prevent red thread from returning in the spring. You also can help prevent red thread growth by avoiding prolonged periods of grass wetness.
To do this, be sure you’re properly irrigating your lawn (if you irrigate it). Only water it between midnight and 6 a.m., and do not water your lawn until it starts to show signs of drought distress.
Additionally, pruning or removing trees or shrubs to increase sunlight and air movement to patches that are susceptible to red thread can keep the grass from staying wet too long. Bag clippings when mowing the affected areas, and wash mowing equipment between uses to reduce red thread’s spread.
In most cases, treating red thread with chemicals isn’t necessary and should be a last resort for extreme infestations.
Expert Help with Red Thread in Maryland & Virginia
At East Coast Lawn, our team of skilled lawn professionals can quickly diagnose and help treat red thread and any number of lawn infestations. We also work hard to keep your lawn in great condition year-round to prevent diseases from taking hold.