Grub Worms

How to Get Rid of Grub Worms in Your Lawn If you’ve noticed brown patches on your lawn that seem to appear out of nowhere, or patches of grass that peel up like carpet, you might be dealing with grub worms. These lawn pests are notorious for destroying healthy grass roots, leaving behind unsightly dead spots.
In this article, we’ll explain what grub worms are, how to tell if you have them, and most importantly, how to get rid of grub worms and prevent them from coming back — especially in Bethesda, Maryland’s temperate climate.

What Are Grub Worms?Grub worms are the larval stage of beetles, most commonly Japanese beetles, June beetles, or chafer beetles.
They are C-shaped, white or cream-colored larvae with brown heads and six tiny legs near the front of their bodies.
These larvae live in the soil and feed on grass roots, which weakens your lawn from below the surface. Over time, heavy grub infestations can cause large patches of dead or dying grass that lift up easily.

Why Grub Worms Are a ProblemWhile a few grubs in your lawn won’t cause major harm, a larger population can quickly destroy turf.
Here’s why grub worms are such a problem for Bethesda homeowners:

• They eat grass roots, causing dead patches and thin turf.
• They attract animals like skunks, moles, and raccoons, which dig up your lawn to eat them.
• They disrupt new grass seed or sod by severing root systems.

If left untreated, grub infestations can turn a healthy green yard into a patchy, brown mess within a single season.

5 Lawn CareSigns of Grub Worm DamageKnowing how to spot grub activity early can save your lawn. Look for these telltale signs:
1. Irregular Brown PatchesPatches of grass that turn brown or wilt even when watered are one of the first warning signs of grubs.
2. Soft or Spongy TurfWhen you walk on your lawn, does it feel soft or bouncy underfoot? That’s often a sign that roots have been eaten.
3. Peeling SodHealthy sod is firmly rooted in the soil. If you can pull up a patch of grass like a loose carpet, it’s a sure sign of grub damage.
4. Increased Animal ActivityIf you notice skunks, raccoons, or birds digging in your yard at night, they’re likely hunting grubs.
5. Visible GrubsDig a small section of your lawn (about one square foot and 2–3 inches deep).
If you find more than 5–10 grubs per square foot, it’s time for treatment.

When to Treat for Grub Worms in MarylandIn Bethesda’s climate, the best time to treat for grub worms depends on the season and their life cycle:

• Spring (April–May):
  Grubs are mature and close to the surface. You can spot and treat them before they become beetles.
• Late Summer to Early Fall (August–September):
  This is the most effective time to treat, as newly hatched grubs are small and easier to eliminate.
• Winter:
  Grubs move deeper underground and are harder to reach, so wait until temperatures rise again.

How to Get Rid of Grub Worms NaturallyIf you prefer to avoid harsh chemicals, there are eco-friendly ways to control grub worms effectively:
1. Nematodes (Beneficial Microorganisms)Microscopic worms called beneficial nematodes are a natural predator of grub worms.
When applied to moist soil, they seek out and infect grubs, killing them within a few days.
✅ Pro Tip: Apply nematodes in early fall or late spring when soil temperatures are above 55°F and the ground is moist.
2. Milky Spore PowderMilky spore is a natural bacteria that specifically targets Japanese beetle larvae.
Once applied, it can continue to protect your lawn for years as it multiplies in the soil.
3. Healthy Lawn MaintenanceA thick, well-watered lawn naturally resists grub infestations.
Mow high (around 3 inches), water deeply, and overseed thin areas in fall to create strong root systems that can withstand light grub activity.

Chemical Treatments for Severe InfestationsIf natural methods don’t cut it, you may need a targeted chemical treatment.
1. Preventative InsecticidesProducts containing imidacloprid, chlorantraniliprole, or thiamethoxam are effective for preventing grub hatchings. Apply these in late spring to early summer before eggs hatch.
2. Curative InsecticidesFor active infestations, look for products containing carbaryl (Sevin) or trichlorfon (Dylox).
These kill existing grubs on contact but work best when grubs are small and near the surface.
⚠️ Always follow label directions carefully and water your lawn thoroughly after applying grub control products to help them penetrate the soil.

How to Prevent Grub Worms from Coming BackThe best way to protect your lawn is through consistent maintenance and seasonal monitoring. Here’s how:

• Aerate your lawn annually to improve soil drainage and root growth.
• Overseed in fall to maintain a dense turf canopy.
• Avoid overwatering — moist soil attracts beetles to lay eggs.
• Schedule a professional grub inspection each year.

Why Hire Lawn Care ProfessionalsAt Lawn Care Bethesda MD, we know how frustrating grub damage can be. Our team offers comprehensive grub worm control, including:

• Soil inspection and grub population analysis
• Targeted natural or chemical treatments
• Seasonal lawn maintenance to prevent re-infestation
• Eco-friendly, pet-safe lawn care programs

We’ll restore your lawn’s health and make sure those grubs don’t come back.


Grub worms are a hidden threat that can cause major lawn damage before you even notice them.
By recognizing the early signs, applying treatments at the right time, and maintaining a healthy lawn, you can keep your yard lush and green all year long.
If you suspect grub damage or just want peace of mind, Lawn Care Bethesda MD can help.

Pro Tip📞 Call today: (301) 
🌐 Visit: www.lawncarebethesdamd.com
We proudly serve Bethesda, Chevy Chase, Rockville, and the surrounding Montgomery County area with expert lawn care, pest control, and fertilization services.