Lawn looking rough? Brown spots, thinning patches, or strange textures can often mean more than just heat stress or bad mowing habits. From underground grubs to fast-spreading fungi, lawn pests and diseases can sneak in quickly and do serious damage. The good news? If you catch them early and know what to look for, most problems can be fixed - sometimes without calling in the pros. This guide breaks down the most common lawn invaders and what you can do to keep your yard healthy, green, and thriving.
Common Lawn Pests and How to Handle Them
Grubs: These beetle larvae live just below the surface, feeding on grassroots. If your lawn feels spongy and lifts up like carpet, you may have a grub issue. Look for increased bird or raccoon activity. Apply grub control products in late summer, or use beneficial nematodes as a natural option. Prevent future issues by keeping your lawn thick and well-watered in early summer.
Chinch Bugs: Found mostly in sunny areas, chinch bugs suck sap from grass blades, leaving behind yellowing, dying patches. They thrive in hot, dry weather. Use the "can test" (sink a can into the soil and add water - bugs will float up). Treat with insecticide or encourage beneficial insects.
Armyworms & Sod Webworms: These caterpillar-like pests chew on grass blades, often creating circular patches of missing grass overnight. Webworms leave behind silky webbing. Spot treat with BT (Bacillus thuringiensis) or a lawn-safe pesticide.
Cutworms: These pests live in the soil and feed at night, cutting grass blades near the base. They're hard to spot but create small dead patches. Apply insecticides in the evening when they're active, or let birds help with control.
Billbugs: Another root-feeder, billbug larvae destroy turf from below. Their damage looks similar to grubs but often starts near sidewalks and driveways. Preventive control is key - treat in late spring before larvae hatch.
Moles & Voles: While they don't eat grass, their tunneling can ruin roots and soil structure. Look for raised ridges or surface trails. Use castor oil-based repellents, traps, or encourage predators like owls.
Lawn Diseases You Should Know
Brown Patch: Caused by a fungus, it leaves large, irregular brown patches in hot, humid weather. Often worsened by overwatering or too much nitrogen. Water early in the day and use fungicide only if necessary.
Dollar Spot: Small silver-dollar-sized spots that can merge into bigger dead areas. Caused by moisture and poor fertility. Improve airflow and apply a balanced fertilizer.
Rust: Orange or yellow powder on grass blades, often seen in late summer or early fall. It's not deadly but indicates weakened grass. Improve mowing, fertilization, and airflow.
Powdery Mildew: White, powdery coating on grass blades in shady, damp areas. Increase sunlight or switch to a more shade-tolerant grass type.
Snow Mold: Shows up in early spring as matted, gray or pink patches. Common in areas with heavy snowfall. Rake and overseed affected areas.
Leaf Spot: Creates dark, purplish spots on blades that spread downward. Most common in wet spring weather. Reduce irrigation and apply a disease-resistant seed variety.
When It's Not a Pest or Disease
Not every lawn issue is caused by bugs or fungi. Some problems come down to basic lawn care habits:
- Overwatering or underwatering can mimic disease symptoms. Lawns usually need 1-1.5 inches of water per week.
- Dull mower blades tear grass rather than cutting it cleanly, leading to frayed, brown tips.
- Pet urine causes concentrated nitrogen burns - look for green rings around dead spots.
- Compacted soil makes it hard for roots to grow and water to soak in. Aeration can solve a lot.
Start with a soil test and evaluate your lawn care routine before reaching for pesticides or fungicides.
General Lawn Rescue Tips
- Dethatch if needed to remove the layer of dead grass between the soil and the green surface. More than ½ inch can choke roots.
- Aerate once a year - especially in high-traffic or clay-heavy areas. It lets nutrients, water, and oxygen reach the roots.
- Overseed thin spots in early fall or spring with a quality seed mix suited for your zone.
- Use organic treatments when possible, like neem oil, compost tea, or corn gluten for pre-emergent weed control.
- Set a mowing height appropriate for your grass type. Taller grass helps shade out weeds and holds moisture better.
Healthy lawns naturally resist pests and diseases better than stressed ones. Focus on building strong roots and the rest will follow.
