The Lawn Man

Fusarium Patch

Caused by: Microdochium nivale (Fr.) Samuels and I.C. Hallett

Fusarium Patch

Plate 1: Fusarium Patch on Poa annua


Symptoms begin as a darkened water-soaked appearance to the grass (Plate 1). The patches enlarge and may develop salmon-pink to orange-brown rings of conidia around the outside of the patch (Plate 2). In conducive weather conditions, white, pink or grey mycelia may grow over the patch surface.

Fusarium Patch

Plate 2: Orange-brown colouration due to conidial production

Where is Fusarium Patch found?

Any area of turf, especially golf greens, tees, fairways and bowling greens

Fusarium Patch is the most common and widespread disease at present in the UK and Ireland

Grass swards dominant in Poa annua, as it is the most susceptible grass species.

When is Fusarim Patch likely to attack turf?

Fusarium Patch can occur at any time of the year during conducive weather conditions. It is most common and damaging during the autumn and winter when the weather is mild and moist. It may also occur during spring in mild temperatures and during summer in warm, humid or thundery conditions.

Effects of Fusarium patch

Fusarium Patch can be a devastating disease on fine turf surfaces as the patches may be many inches in diameter and adversely affect the playing surface as well as its aesthetic value.

Poa annua grass may ingress into the scars left by Fusarium Patch

High risk situations

Poa annua grass dominant sward

Very humid conditions

Poor surface drying due to shading and no air movement

Over-fertilised soft grass growth

Alkaline rootzone conditions

Excessive thatch layer

Heavy top-dressing during conducive weather conditions

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