Rusts are fungal diseases that have many different species affecting a wide variety of plants and grasses. Most turfgrass species are susceptible to Rust diseases and unlike other fungal diseases, it will happily attack healthy turf.
Orange pustules of spores appear on the underside of leaves and help to identify the disease. The spores spread an orange to red coloured dust on the affected grasses. Initially, these irregular patches of discolouration will appear on the leaves but as the disease takes hold will work their way down the stem.
When does Rust occur?
Most common on ryegrass but can infect other species as well. Rust generally occurs in cool weather when the turfgrass is not growing rapidly. It favours low-lying, wet leaves and prolonged leaf wetness increases infection.
What damage or effect will Rust have?
With severe infection turf density can become thin and chlorotic (yellowed). It does not always kill the turf but may weaken it to a point that it becomes vulnerable in the presence of other diseases.
How to eliminate Rust from turf
Treatment for Rust is currently under research.
Bayer recommends Dedicate Turf and Ornamental Fungicide to control Rust.