Rust Diseases of Turf (Various): Leaf Rust, Uromyces spp.; Crown Rust, Puccinia coronata; Strip Rust, Puccinia striiformis; and Stem Rust, Puccinia graminis
From Rust on Turfgrasses, New Mexico State University. Photo by R. S. Byther, Washington State University.
IPM Steps to Reduce Rust Diseases of Turf
1. Sample for Pest
Confirm the presence of rust before you treat.
Where to find it while inspecting: On turf blade. Will begin as light green or yellowing areas and then appear as brown or orange blades in grass that has been subjected to favorable conditions for fungal growth. Active rust disease also shows up by reddish “dust” on shoes and tires. Can be found on Kentucky bluegrass, perennial ryegrass, fescues and zoysiagrass.
2. Proper ID
Is it a rust disease?
Size and Appearance: Begins as small rust color, raised spots on turf blade and spreads across turf blade (dependent on particular fungal disease) as spots or stripes.
3. Learn the Pest Biology
From Rust on Turfgrasses, New Mexico State University. Photo by D. Settle, Kansas State University.
What is the life cycle of rust disease?
Life Cycle: Rusts survive in soil and plant material and become active in specific weather conditions. Cool to warm, moist weather favors infections and leaf wetness is needed to spread infection. Even one day of long-term dew on leaves can facilitate infection. Most turf rust diseases need a host plant to complete their life cycle (each disease has a list of favored herbaceous or woody plants that work for this part of the life cycle). Rust starts as flecks that enlarge into ruptures on the blade surface (pustules). Pustules contain orange spores that spread easily.
Preferred Food Sources: Rusts obtain nutrients through the breakdown of organic matter.
Preferred Habitat: Turf with neighboring plants that act as hosts (varies by disease).
4. Determine Threshold
How much rust is too much?
Threshold: This depends on vigor of turfgrass plants affected and weather conditions that slow or extend damage. Turfgrass rust often goes untreated on most school grounds.
5. Choose Tactics
Creating a healthy soil condition and understanding turfgrass needs is the first step in reducing turf pests.
Best Management Practices: Reduce shade on turf by thinning or removing shrubs and trees (this also reduces humidity and increases air flow). Maintain appropriate fertilization, not over fertilizing, avoid watering in evening, water deep but infrequently, keep turf at tallest height for species to reduce stress, mow regularly to reduce bulk of leaf material and aid drying, reduce thatch, overseed with resistant varieties or mixed varieties.
Treatment Methods: Where allowed, fungicides may be appropriate in some instances.
Was the tactic successful? Record the date pests were first noted, and the tactic you used, and its success. Use one of our RECORD KEEPING tools.
For More Information:
When a pesticide application is necessary, all necessary and required precautions are taken to minimize risk to people and the environment and to minimize risk of pesticide resistance or pest resurgence. Pesticide use in your school may be prohibited or regulated by local policies or state and federal regulations. Risk reduction methods can include, but are not limited to, spot-treatment, the use of gel or paste bait formulations placed in inaccessible locations, injection into a crack or crevice, and other methods that reduce potential exposure.