Alfalfa Diseases in Ohio

Lepto leaf spot

• Symptoms
  • small dark specks on leaves
  • lesions enlarge to oval eyespots with tan centers and dark brown borders
  • lesions usually surrounded by yellow halo
  • lesions parallel to leaf veins
• Environment
  • extended wet periods
• Survival
  • overwinters in dead alfalfa residue
  • spores spread by wind
• Management
  • resistant varieties
  • use four-cut system vs. three-cut system
  • fungicide is available
• Scouting