The Lawn Man

Red Thread

Caused by: Laetisaria fuciformis (McAlpine).

Red Thread

Plate 1: Red needles and pink flocks of mycelium


The symptoms depend on the grass species and severity of attack. Symptoms often start as small mostly circular patches of dead leaves interspersed with live plants. The patches may also have a pink tinge (Plate 2). Closer inspection will reveal pale pink to red needle or horn-like outgrowths (the red threads - Plate 2) Pink flocks of mycelium (resembling candyfloss) may also be present in conducive conditions.

Red Thread

Plate 2: Symptoms of red thread

Where is red thread found?

Any area of turf, especially golf greens, tees, fairways, bowling greens, lawns, parkland and sports pitches

When is red thread likely to attack turf?

When growing conditions are good infection may be transient but under poor growing conditions attacks may be severe

Effects of red thread

Red thread does not commonly affect the playing quality of the turf but reduces the aesthetic appearance.

Red thread may thin the sward.

High risk situations

Fescue is the most severely affected, although there is variation among subspecies and cultivars. Lolium perenne is also very susceptible.

Low fertility.

Warm and wet conditions.

Slowly growing turf.

Moisture retentive turf surface

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