Caused by: Sclerotinia homoeocarpa
Dollar Spot causes sunken, circular patches that measure up to 5 cm in diameter on golf greens and several inches on higher mown turf. The patches turn from
brown to straw colour and may eventually coalesce, forming irregularly shaped areas. Infected leaves may display small lesions that turn from yellow-green to
straw colour with a reddish-brown border. The lesions can extend the full width of the leaf. Multiple lesions may occur on a single leaf blade.
Dollar Spots coalescing.
All species of warm- and cool-season turfgrass.
Conditions favouring Disease
Dollar Spot is favoured by temperatures between 15°C to 30°C and continuous high humidity.
This disease is particularly favoured by warm days, cool nights, and intense dews.
It also infects areas with low levels of nitrogen and becomes more severe in dry soils.
Integrated Turf Management
Use an adequate level of nitrogen, particularly in the Spring and early Summer.
Mow grass at regular intervals.
Increase the air circulation.
Irrigate turf deeply and as infrequently as possible to avoid drought stress.
Remove dew from the turf early in the day.
Convert to a turfgrass cultivar (especially for Bentgrass) that is more tolerant to Dollar Spot.
Apply contact and/or penetrant fungicides on a preventive basis.
South Africa Turf Disease Guide
Download a copy of the Syngenta Turf Disease Guide 2020 for South African golf courses and all turf and grass surfaces.