Diagnosing and Treating Lawn Rust Fungus

A lawn has had rust for two years after 20 rust-free years. The owner fertilizes 3-4 times annually and mows frequently. The summer was cool and wet. The expert notes that "rust" is a generic term for several fungi. It could also be iron from well water causing discoloration. Accurate identification (via lab or extension) is essential for targeted treatment, which may involve adjusting watering timing/frequency or applying a fungicide.