If you ever doubted that your lawn could suffer from 'rust' then keep reading.....
Rust Disease - Puccunia and Uromyces
We are more used to seeing rust on our first car than our lawn! Infected turf appears generally yellow/orange. Close examination reveals the leaves with orange fungal pustules which, when touched, disperse large numbers of uredospores. These are very similar in appearance to the rust dust, which can be wiped from rusty metal, hence the name.
When is it normally seen on lawns?
During cool weather in summer and autumn. Initial symptoms show as yellow flecks on the leaves and plant stems. These flecks enlarge and the fungal spores develop on the leaf surface.
This disease does not usually cause serious problems on U.K. turf and the problem is more of a visual one although left un treated the small areas can merge to become large unsightly areas. This picture shows a close up of the rusty spots on the upper surface of the grass plant leaf. The rusty dust can literally come off on your finger as you gently pass it through your thumb and forefinger. When you walk through a rust infected area of turf your shoes can turn orange!
Will it kill the lawn, left untreated?
Rust Disease tends to be present on Rye Grasses and Smooth Stalked Meadow Grass.
Rust disease is normally seen on long grass and poorly under nourished turf, especially when the air temperature is above 20 degrees centigrade. Grasses that are stressed as a result of poor nutrient levels, shade, and lack of moisture and presence of other turf grass diseases such as Fusarium and Red Thread Diseases.
What are my options on control of the disease?
The best remedy is to reduce the causes of the stress the grasses are under and to increase the nutrient levels. A slow release balanced fertiliser containing some Potassium will enable the grass plants to naturally ‘toughen up’ to ward off future disease and pest attacks.
You may need to have a professional quality turf fungicide applied, which will have a contact and systemic mode of action. A repeat may be required within a 6-week period. The fungicide will dry the fungal spores out and then help the grass fight the disease from within.
The Sports Turf Institute and Grass Seed Breeders work hard to develop turf grasses that are more resistant to outbreaks of this disease. Choose a grass seed cultivar that has the highest listed ‘resistance to Rust Disease’
Football Pitches, which are predominately 100% Rye Grasses often get an attack along with Leaf Spot Disease when the evening and night time temperatures dramatically dip at the end of the Summer. They will spend a lot of their financial budget applying fungicide treatments to ward off future attacks and increase Potassium levels too.
A downloadable .PDF version Rust Disease is available here