Red Thread: Diagnosis and Treatment

Identification and Control


Red Thread

Red thread is a fungus-based lawn disease also known as “pink patch.” Most prevalent in cool, humid climates or on damp turfgrasses that are deficient of nitrogen, there are ways to diagnose and treat red thread so you can restore your lawn’s health and beauty. Read on and learn how.

Diagnosing Red Thread

Once infected, grass leaves develop water-soaked spots that grow and dry out the tissue. This bleaches the grass blades to a creamy, tan color. Pinkish fungal growth forms in moist conditions that result in coral-pink-colored branching threads. As the threads spread, the lawn takes on reddish patches that vary from 2″ to 3′ in diameter. The patches join together and create larger patches if left untreated.

Red Thread Treatment

Low soil fertility and inadequate nitrogen levels are usually the culprit when red thread appears. Nitrogen is best applied at .5 oz per square yard in the form of sulphate of ammonia. When treating for nitrogen, though, you are potentially leaving your lawn vulnerable to other diseases. Adjust your watering schedule and adhere to a balanced fertilizing program to prevent and treat red thread.

Red thread is spread by fungal spores, so containment is important in preventing the uninfected areas from being contaminated. Avoid walking on the grass, mow infected areas separately, and dispose of grass clippings immediately.

Fungicides are often not necessary when treating red thread, especially if it’s caught before the advanced stages. Have your neighborhood lawn care expert administer a professional-grade fungicide in the spring and fall if you go this route. This ensures the best (and safest) results. At-home fungicides are available at garden supply stores. Choose a formula containing trifloxystrobin,  benomyl, or carbendazim and consult the package for instructions.

Call in the Experts

Still not sure if you’re dealing with red thread? Call the professionals at Cardinal Lawns for help diagnosing and treating this pesky lawn disease.

Lawn Disease Guide

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Even the most manicured landscapes are susceptible to lawn disease. Take some time to learn about identification and removal before one takes over your lawn. This handy guide teaches you how to spot common lawn diseases as well as how to properly treat them.