Caused by: Bipolaris sorokiniana (Sacc.)
Shoemaker, Curvularia spp., Dreschlera spp.
Plate 1: Dreschlera siccans
Symptoms depend on the grass species and the pathogen
involved. Generally a yellowing or paling of the leaf blades may
occur, accompanied with spots or lesions developing (Plate 1.
Lesions may girdle the leaf and the portion above the girdle
withers. The sward may thin or look drought stressed.
Creeping Red Fescue, Kentucky Bluegrass, Annual Bluegrass,
Perennial Ryegrass, tall Fescue, and some varieties of Bentgrass
Where is Leaf Spot found?
Any area of turf, especially golf greens, tees, fairways,
, lawns, parks and sports pitches. All grass species can be
affected by Leaf Spots.
When is Leaf Spot likely to attack turf?
During the summer months, when the temperatures are high.
Humid conditions encourage outbreaks.
Effects of Leaf Spot
Minor infection may result in lesions on leaves but no
other effects. Severe infection may thin the sward, cause dieback
and leave patches with weak turf, affecting the aesthetic value and
the playability of the turf.
High Risk Situations
- Leaf spots occur in mild and warm temperatures (around 20ºC).
As the temperature increases (25 - 35ºC) blighting and melting out
- High fertility
- Moist conditions
- Cutting heights lower than recommended for the grass
- Excessive thatch layers