Brown Spots in Warm-Season Lawns: Drought Stress, Fungus, or Lawn Pests?

Brown spots can appear quickly in warm-season lawns, especially during Central Texas summers. But not every brown patch has the same cause. A lawn may be turning brown because it needs more water, is being affected by a fungus, or has damage from lawn pests.

The right solution depends on what is happening in and around the affected area. Before applying a product, take a closer look at the pattern, the soil, and the grass itself.

If you are unsure what is causing the problem, send Marshall Lawn Solutions a few pictures. We can help you identify what to look for and determine whether the lawn may need further evaluation.

1. Drought Stress From Lack of Watering

Warm-season grasses need consistent moisture to stay healthy, especially during periods of high heat. In Central Texas, hot temperatures, dry conditions, wind, and watering restrictions can quickly put stress on a lawn.

What drought stress may look like

Drought-stressed grass may:

• Turn dull green, brown, or straw-colored
• Look thin or wilted
• Show footprints that remain visible after walking across the lawn
• Develop brown areas in places that receive less water
• Look worse near sidewalks, driveways, and other hot surfaces
• Improve temporarily after thorough watering

Brown spots caused by watering problems are often irregularly shaped. They may also follow the pattern of a sprinkler that is clogged, misaligned, or not reaching the entire lawn.

What to check

Walk through the affected area and check the soil. If the soil is dry several inches below the surface, the grass may not be receiving enough water. Also inspect your irrigation system for:

• Clogged sprinkler heads
• Broken or tilted heads
• Uneven coverage
• Water running off compacted soil
• Areas blocked by landscaping, fences, or other obstacles

It is also important to avoid assuming that more water is always the answer. Frequent, shallow watering can encourage shallow roots and may create other lawn problems. Your lawn’s watering needs depend on the grass type, soil, weather, shade, and local watering requirements.

2. Fungus or Turf Disease

Fungal problems can also create brown spots or patches in warm-season lawns. Central Texas heat, humidity, heavy dew, poor air movement, and extended periods of wet grass can create conditions that favor turf disease.

What fungus damage may look like

Fungus-related damage may appear as:

• Circular or irregular brown patches
• Rings or areas that seem to expand over time
• Thin, yellowing, or browning grass
• Small spots on individual grass blades
• Brown areas that remain even when the soil has adequate moisture
• Damage that appears after warm, humid, or wet weather

Some fungal issues begin as small spots and spread. Others may affect larger areas of turf. The pattern and condition of the grass blades can provide useful clues, but fungal problems can be difficult to identify accurately without a closer inspection.

What to check

Look at the grass during the early morning, when dew may make symptoms easier to see. Check for unusual discoloration, spots on the blades, or areas where the grass is thinning.

Good watering practices can help reduce conditions that encourage some lawn diseases. Try to avoid watering late in the evening when grass may remain wet overnight. However, changing the watering schedule alone may not correct an established fungus problem.

If fungus is suspected, the lawn may need a professional evaluation and an appropriate fungus control treatment. Applying the wrong product can waste money and may delay the right solution.

3. Lawn Pests and Insect Damage

Lawn pests can damage grass by feeding on the blades, crowns, roots, or soil around the turf. The result may be brown or thinning areas that continue to worsen even when watering appears adequate.

Common lawn pests can include insects such as grubs, chinch bugs, and other turf-damaging pests. The symptoms can vary depending on the pest and the type of grass.

What pest damage may look like

Pest-related brown spots may:

• Begin as small areas and gradually spread
• Appear in sunny or stressed sections of the lawn
• Cause grass to thin or pull up easily
• Occur even when the soil has sufficient moisture
• Attract birds, armadillos, or other animals looking for insects
• Show signs of insect activity near the soil or grass roots

For example, insects that feed on grass roots can make the turf feel loose or cause it to lift easily. Other pests damage the grass above the soil and may create yellow or brown patches during hot weather.

What to check

Gently pull on the grass in the affected area. If it comes up easily and has few roots attached, inspect the soil beneath it for grubs or other insects. You can also look for insects around the base of the grass and along the edges of the damaged area.

Avoid treating the entire lawn automatically just because you see one brown spot. First, try to determine whether pests are actually present and whether they are the cause of the damage. The correct treatment depends on the pest, the timing, and the type and severity of the damage.

Brown Spots Can Have More Than One Cause

Sometimes a lawn is dealing with more than one problem. For example, drought stress can weaken grass and make it more vulnerable to pests or disease. Uneven watering can also create dry areas next to sections that stay too wet.

That is why it helps to pay attention to:

• When the brown spots first appeared
• Whether the spots are spreading
• Recent rainfall and irrigation
• How quickly the grass changes after watering
• Whether the area is shaded or exposed to full sun
• The shape and location of the spots
• Any insects, animal activity, or unusual signs in the soil
• Recent mowing, fertilization, or lawn treatments

A picture of the entire lawn, a closer picture of the affected area, and a picture of the grass blades or soil can all be helpful.

Send Us Pictures of Your Brown Spots

Brown spots do not always mean your lawn is dying, but they are worth investigating. Paying attention early can help you avoid guessing and applying a treatment that does not address the actual problem.

If you notice brown spots in your warm-season lawn, send Marshall Lawn Solutions pictures of what you are seeing. Include:

1. A wide photo showing where the spot is located
2. A closer photo of the affected grass
3. A photo of the surrounding healthy grass
4. Any close-up pictures of insects, damaged roots, or unusual markings

We can help you think through whether the problem may be related to watering, fungus, pests, or another lawn condition. When needed, we can recommend the next step based on what is actually happening in your lawn.

Marshall Lawn Solutions provides weed control, fertilization, insect control, fungus control, soil amendments, and lawn-care guidance for Central Texas lawns. Our goal is not simply to treat a symptom—it is to help you understand what your lawn needs to stay healthy, thick, and green.

Have brown spots in your lawn? Send us a picture and let us help you take a closer look.

Can you tell the difference?