Lime-Green Spots in Utah Lawn: Iron Deficiency, Fungus, or Webworms?

Diagnosing Lime-Green Patches

• Iron deficiency: Causes yellow-green (chlorotic) patches. Iron supplements help if pH is high.
• Fungal disease: Grass blades "lay down," feel slimy when pulled. Treat with baking soda (¼ cup/gal) or corn gluten meal.
• Sod webworms: Cause brown patches, not lime-green. Check for frass (green pellets) at thatch level.

Immediate Actions

1. Test soil pH—high pH locks up iron.
2. Apply chelated iron if deficient.
3. Spray baking soda solution on suspicious patches as precaution.
4. Monitor for webworm signs (silk tunnels, frass, moths at dusk).

Organic Fungus Treatments

• Baking soda spray (¼ cup/gal)
• Corn gluten meal (also pre-emergent weed control)
• Agricultural cornmeal

All safe, non-toxic, and soil-building.