White Grubs in Your Killeen TX Lawn — How to Identify and Treat Them

Most Killeen homeowners know about fire ants. Fewer know about the damage happening underground—grubs tunneling through the root zone of Bermudagrass lawns, severing the roots that keep the grass alive and green. If you have brown patches in your lawn that won’t respond to watering and pull up easily like loose carpet, grubs may be the cause.

White grubs are the larval stage of several beetle species common in Central Texas, and they’re responsible for brown patches that no amount of surface treatment will fix. Understanding when grubs are active and when treatment is effective can save a Killeen lawn from significant damage.

What Are White Grubs?

White grubs are the larvae of beetles from the Scarabaeidae family. In Central Texas, the most common species are June beetles (June bugs) and masked chafers. The adult beetles are the clumsy insects that crash into porch lights in late spring and summer—their larvae are what end up in your lawn.

The lifecycle follows a predictable pattern each year:

• Late May to July: Adult beetles emerge and mate. Females burrow into irrigated lawns to lay eggs, typically in June and early July.
• Late July to August: Eggs hatch. Tiny first-instar larvae begin feeding near the surface.
• August to October: Larvae grow through second and third instar stages, feeding aggressively on Bermudagrass roots at 2–4 inches below the surface. This is when lawn damage becomes visible.
• November to February: Grubs move deeper into the soil to overwinter. Active feeding stops.
• Early spring: Grubs move back toward the surface briefly before pupating and emerging as adult beetles.

Signs of White Grub Damage in a Killeen TX Lawn

White grub damage closely resembles drought stress and Bermudagrass dormancy—all produce brown patches. The difference is in how the lawn behaves and what you find underneath.

Signs that point to grubs rather than drought or dormancy:

• Brown patches appear in late summer (August to October) during the normally active growing season
• The brown area doesn’t improve after watering—drought-stressed lawns recover quickly with water, grub-damaged lawns don’t
• The grass pulls up easily, like loose carpet, because the root system has been severed
• Digging 3–4 inches into the soil reveals C-shaped, white or cream-colored larvae with orange-brown heads, ranging from ½ to 1 inch long
• Increased digging activity from birds, raccoons, or armadillos—they are hunting grubs

The pull-back test: Grab a corner of the brown patch and pull. If the turf lifts in a sheet with no resistance—like peeling back a rug—you almost certainly have grubs. Healthy Bermudagrass roots anchor the turf firmly to the soil.

How Many Grubs Are Too Many?

Not every lawn with grubs will show visible damage. A threshold of 5 to 10 grubs per square foot is generally considered the level at which healthy Bermudagrass begins to show visible injury. To check, cut out a 1-square-foot section of sod to a depth of about 4 inches and count the grubs in that sample. Take samples in both the damaged area and in apparently healthy adjacent areas to compare.

Fewer than 5 grubs per square foot in a well-irrigated Bermudagrass lawn may not require treatment—the grass can compensate with continued root growth. Above that threshold, particularly in combination with visible brown patches and the pull-back test, treatment becomes warranted.

When Grub Treatment Is Most Effective

Timing is everything with grub control. The most effective treatment window is when larvae are young, small, and feeding near the soil surface.

The ideal treatment window for Killeen TX is June to early August—shortly after egg-hatch when larvae are in the first and second instar stage. Preventive treatments applied in June, before visible damage appears, are far more effective than rescue treatments in September after damage is already done.

Products containing chlorantraniliprole or imidacloprid applied to moist soil and watered in are commonly used for grub control. They need time to move through the soil to where larvae are feeding—which is why early application matters.

Rescue treatments in fall (September–October) can reduce grub populations but are significantly less effective. By late fall, larvae have grown larger, are more resistant, and may be moving deeper into the soil.

Resist the temptation to treat preemptively without confirming grub presence. Unnecessary insecticide applications are expensive and can impact beneficial soil organisms.

Repairing Grub Damage

Once grubs are controlled or have moved deeper in fall, the lawn needs help recovering. Bermudagrass has good recovery potential if some roots remain, but heavily damaged areas where the root system was completely severed will need intervention.

For partial damage: Ensure the lawn receives adequate water and nutrition. Bermudagrass spreads aggressively via stolons and can fill in moderate damage on its own within a few weeks given good growing conditions and warm temperatures.

For heavy damage: Large areas where the turf pulled up like carpet may need to be re-established with sod or plugs. Fall re-sodding in Killeen works if done early enough (September) to allow roots to establish before dormancy. If the damaged area is extensive and brown going into winter, evaluate again when Bermudagrass breaks dormancy in spring. Areas that don’t green up with the surrounding lawn by late April may need professional lawn renovation.

Why Healthy Lawns Handle Grubs Better

A Bermudagrass lawn with a deep, healthy root system tolerates more grub feeding before showing visible damage. Stressed lawns—those with compacted soil, inadequate water, or thatch buildup—show damage at lower grub counts because they have less root mass to lose.

This is one of the reasons core aeration supports long-term lawn health in Killeen’s Blackland Prairie clay soil: breaking up compaction allows roots to grow deeper and more densely, giving the lawn better capacity to withstand root-feeding pests.

Consistent lawn maintenance—regular mowing, appropriate fertilization, and proper irrigation—produces the type of dense root system that outcompetes pest damage. A healthy lawn simply tolerates more than a stressed one.

Armadillos as a Grub Indicator

Armadillos are well-established across Central Texas and will dig up a lawn aggressively to reach grubs. The secondary damage from armadillo digging—cone-shaped holes every few inches across a large area—is sometimes more visually dramatic than the grub damage itself. Eliminating the grub population removes the armadillos’ food source, which typically causes them to move on.

Grubs Compared to Other Lawn Pests

White grubs feed on roots and cause damage from below, making large patches loose and brown. Other common Killeen lawn pests work differently:

• Fire ants build mounds and sting but don’t directly damage turf roots. See the fire ant guide for treatment approaches.
• Chinch bugs are surface feeders that affect St. Augustine grass in hot, sunny areas, leaving yellowed (not loose) patches.
• Nutsedge and weeds compete with grass but don’t damage roots directly.

For a broader seasonal view of lawn care through the active pest season, the Killeen TX lawn care calendar covers each season’s relevant concerns alongside fertilization, mowing, and weed control timing.

Frequently Asked Questions

How do I know if my lawn has grubs or is just drought-stressed?

Water the brown area thoroughly for several days. Drought-stressed Bermudagrass recovers within a week of consistent watering. If the area stays brown and the turf pulls up easily when you tug at the corner, grubs are likely responsible.

Can I treat my lawn for grubs myself?

Granular grub control products are available at home improvement stores. Effective timing and proper application—applied to moist soil and immediately watered in—is critical. Many homeowners apply at the wrong time of year and see little result. If you’re not certain about timing or identification, professional assessment and treatment is usually more cost-effective than repeated DIY attempts.

Do grubs come back every year?

June beetles complete their lifecycle annually. If adult beetles are present in your area, they will lay eggs in healthy, irrigated turf each summer. Annual preventive treatment may be appropriate if you’ve had repeated infestations, but confirm grub presence before treating each year.

Will grubs kill my entire lawn?

Rarely. Grubs typically damage areas within a lawn rather than an entire property. Bermudagrass can recover from moderate damage with proper care, but heavily infested areas with complete root severance will need re-establishment.

What time of year should I look for grubs?

Check in late August through September when second and third instar larvae are actively feeding and large enough to find easily. Dig 3–4 inches in brown patches and compare grub counts with adjacent healthy areas.