Identification

• According to the University of Illinois Extension, rust fungus grows slowly on grass. Hot, dry weather favors development of rust fungus, which commonly develops in Kentucky bluegrass, ryegrass and tall fescue.
  
  

Symptoms

• Rust fungus is characterized by an orange or reddish fungal growth on grass blades. Rust spores rub off on your hands and shoes, spreading the disease. Other means of spreading rust fungus are through the air, wind or water. Rust fungus makes grass more susceptible to other diseases and pests.
  
  

Control

• Keeping your lawn in good health is one way to prevent rust fungus. Applying fertilizer and adequate water also prevents rust development. Fungicides are often necessary to protect new grass when rust is severe and destructive. Contact your local extension office for advice on fungicides recommended for the treatment of rust fungus.