What is Red Thread Fungal Infection

If your lawn is developing straw coloured patches, about the size of a saucer to a dinner plate, your lawn might well be infected with Red Thread.

Red Thread is the most common fungal disease that attacks the majority of lawn grasses. It is particularly serious on perennial ryegrass (Lolium perenne), annual meadow grass (Poa annua), and fescues such as red fescue (Festuca rubra).

The fungus (Laetisaria fuciformis) favours mild, damp weather when the canopy of the grass becomes humid, such as during late Summer, but it can develop at any time of the year when the conditions are conducive. It takes two forms, the form that gives the disease its name can be identified by very thin strands of grass that protrude from the grass blade. These strands are coloured red or pink and called stromata. If not treated they can remain within the soil for up to two years. The second form of the disease takes the form of pink cotton wool or a candy floss-like substance, usually in the crown or on the upper tips of the grass blade. This is mycelium and is usually most visible during wet but humid weather conditions.

Red thread is soil-borne but the disease can be spread by water and strong winds and can be moved around by the cutting of your lawn. It is the red or pink strands and also the mycelium that allows the disease to spread. Red Thread can live in soil for many years before making an appearance on your lawn.

If you suspect that your lawn is infected with Red Thread fungus why not take advantage of the Lawnscience lawn review service. One of our fully trained lawn care professionals will be happy to arrange a lawn review with you, during which they will identify the issue(s) and provide you with a fully costed solution for you to consider. To take advantage of this opportunity just click on the orange Help Please button below.

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