How to Identify and Treat Bug Damage in Your Lawn

Blake Rey • April 9, 2024

A detailed guide on how to combat bug infestations in your lawn

Main Takeaways from This Article:
  • Identify bugs and their damage
  • Assess the damage and determine the best treatment course
  • Learn about sod webworms, chinch bugs, grubs, mole crickets, and ants

Questions Answered in this Article:
  • How do I identify sod webworms in my grass?
  • How do I treat a sod webworm infestation?
  • How do I identify chinch bugs in my grass?
  • How do I treat a chinch bug infestation?
  • How do I identify grubs in my grass?
  • How do I treat a grub infestation?
  • How do I identify mole crickets in my grass?
  • How do I treat a mole cricket infestation?
  • How do I identify ants in my grass?
  • How do I treat an ant infestation?
Identifying bug infestations is a key part of keeping your lawn looking green and healthy. Stopping them in their tracks before they further damage your lawn is important. That’s why we’ve decided to create a guide to help you keep those bugs out of your grass! In this article, we’ll teach you how to identify those bug infestations and how to take care of them. We’ll cover the most common bugs that you may find in your grass and how to treat them.

How do I identify sod webworms in my grass?


Sod webworms are caterpillars named so because of the web-covered tunnels they burrow beneath the grass to hide during the day. Sod webworms are nocturnal, so they usually only come out to feed at night. They start as caterpillars smaller than a centimeter long, then pupate, and finally transform into white-tan moths. The moths then fly from grass to grass, mating and laying their eggs across your lawn. The white moths usually rest on the grass blades, so you can tell if you have them simply by walking in a suspected infestation area and watching the moths fly away.


Photo Credit: James Kerrigan, UF

  • Sod Webworm Larvae Stages

    Slide title

    Various stages of sod webworm larvae.

    Button
  • Sod Webworm Moth

    Slide title

    Mature sod webworm moth.

    Button

The damage that sod webworms do to the grass looks like a brown patch upon first glance. Up close, you may notice that the individual blades of grass are chewed through, either from the top or sides of the blades. This will cause the grass to yellow and brown as it experiences stress. The damage will spread at a moderate speed, meaning that the grass is still salvageable after leaving the sod webworms alone for one to two weeks. However, the sooner the infestation is dealt with, the better. The damage will become harder to treat once there is a widespread population of moths across the lawn.


Photo Credit: Steven Arthurs, UF

  • Sod Webworm Damage St. Augustine

    Slide title

    Sod webworm damage on St. Augustine grass.

    Button
  • Sod Webworm Damage St. Augustine

    Slide title

    Sod webworm damage close up.

    Button
  • Sod Webworm Damage St. Augustine

    Slide title

    Sod webworms have chewed through the sides of the blade.

    Button
Sod Webworm Eating Thatch


If you are inspecting your grass during the day, a great way to spot these bugs is to dig through the thatchy and damaged areas of your grass. Watering the soil may help bring the sod webworms closer to the surface. Since they are nocturnal, the likelihood of you seeing them feeding during the day is low. Scrape through the top level of the soil, and you may find some larvae lurking beneath the surface.


Photo Credit: Steven Arthurs, UF

Bioadvanced Grub Killer Plus


How do I treat a sod webworm infestation?


The best way to treat an infestation is with two applications of different insecticides. The first treatment will be with our Grub Killer Plus. It kills subsurface insects within 24 hours of being spread. The best way to apply it would be to wait until close to dusk so that you can catch the sod webworms as they wake up and come to the surface to feed. Before you do that, briefly run your sprinklers for five minutes to coax the sod webworms into coming to the surface. Spread the insecticide over your whole lawn to prevent the possibility of a stray bug traveling to another part of your lawn. Use your own push spreader or one of our Scatter Boxes to spread the bag. Make sure to check the broadcast settings on the bag so that your spreader spreads the insecticide properly. Water the insecticide in so that it incorporates itself into the soil by running the sprinklers for 15 minutes.

Scott's GrubEX

In addition to the Grub Killer Plus, use GrubEX for lasting protection on your lawn. There is a high probability that if you had spotted sod webworm damage in your lawn, the bugs may have already matured into moths. The moths will fly away from your lawn, lay eggs somewhere else, then come back a month or two later. Grub EX protects your lawn for up to four months. It makes it ideal for keeping those moths away, especially since directly killing them is unfeasible.

Chinch Bug Stages of Maturity


How do I identify chinch bugs in my grass?


Like with most infestations, signs of chinch bugs will appear at first glance in a brown patch of your yard. Chinch bugs are very small insects, with the nymphs reaching about 1 mm and the adults reaching about 5 mm. This makes them difficult to spot with the untrained eye. They have different stages of maturity as well; the young are orange with a white stripe, the middle stage bugs are black with short wings, and the mature adults are black and white with orange legs.


Photo Credit: Lyle Buss, UF/IFAS

Chinch Bug Damage St. Augustine


The damage they deal will leave the grass looking crispy. They suck the juices out of the blades of grass, making them withered and dried. It saps the life out of grass quickly, making chinch bugs irritating if not caught early on. If they are left to feed on the grass, they will spread extremely quickly, leaving your lawn looking poor in a matter of a week or even a few days.


They are most likely to be found in full-sun areas of your grass that are particularly hot and dry. For residential properties, they are most common by the side of the road or sidewalk, since asphalt and concrete will heat up and dry out the connecting grass. From those points, the chinch bugs will spread further along the edge of the grass and inward to the center of the lawn. If you wish to check for the bugs yourself, inspect the threshold between the healthy looking grass and the grass that has already died. If you want to get a better look, dig up a chunk of grass there with soil and place it on a white or light colored surface. This will make it easier to spot the bugs as you sift through the affected area.


Photo Credit: Adam Dale, UF/IFAS

Valent Arena Insecticide


How do I treat a chinch bug infestation?


If you have confirmed the infestation, treatment should begin as soon as possible. Since chinch bugs spread very quickly, it is best to kill them with an insecticide as soon as the problem is diagnosed. Use our Kill-a-Bug insecticide to treat the problem. Make sure to cover the whole lawn to protect against potential spreading. Alternatively, if your infestation is particularly bad or if you have a large area to cover, our Valent Arena insecticide is one of the best on the market. It is often used on golf courses but is suitable for residential lawns. It covers up to 10,000 sq. ft. and lasts up to 3 months to give your lawn season-long protection.


HuMic Acid


In addition to insecticide, you can protect the areas of your lawn that are particularly hot and dry by giving them extra water as a preventative measure. Make sure your sprinklers give you an even coverage of the lawn. You can also rake up or break down thatchy areas of your grass to prevent chinch bugs from setting up stations in your lawn. HuMic Acid is one of the best products to use to break down thatch in your lawn and reintegrate it into the soil.

White Grub Chafer Beetle


How do I identify grubs in my grass?


Grubs are large, white larvae found in the soil beneath the grass. They can grow up to two inches long and are usually found curled in a C shape. They are a part of the chafer beetle group, meaning that they mature into beetles once sufficiently sized. They feed on the roots beneath the grass.


Photo Credit: J.L. Castner, UF

Grubs Under Grass


Damage is typical: the blades of grass turn yellow, then brown. As the grubs spread, the brown patch will spread as well. A good way to diagnose the problem is to pull the affected area up. Cut about two inches below the base of the grass on three sides like a square, leaving one side attached to the ground. Pull the piece of grass up, and you should notice two things if it is a grub infestation. One is the ease of pulling the grass; if grubs ate it, the grass would be easy to pull since the roots are damaged. The second is the actual presence of grubs. They will be in the ground relatively close to the surface and will be lying in the C shaped position. Thankfully, due to their size and color, they should be easier to spot than most other sod-infesting bugs.


Photo Credit: Kevin Frank, MSU


How do I treat a grub infestation?


Grub infestations spread relatively slowly, so the damage doesn’t manifest noticeably until the local population grows larger. Treating the problem early can definitely help, so using a product like our
Grub Killer Plus is one of the best ways to go for an immediate effect. To maximize the effectiveness of this product, water the grass briefly before you spread the insecticide to coax the grubs to come closer to the surface. After you water, spread the insecticide, then water the insecticide in so that it reaches the grubs faster.


Like with sod webworms, if you want season-long protection from grubs,
GrubEX is the best option for that. It protects your lawn from grubs for up to four months, so you don’t have to worry about looking out for damage on your grass to identify the problem. It takes effort out of the equation in keeping bugs out of your lawn!

Mole Crickets


How do I identify mole crickets in my grass?


Mole crickets are an insect that creates tunnels and burrows beneath the grass to feed on its roots. There are three types of invasive mole crickets that are harmful to your grass: short-winged, southern, and tawny (pictured left to right). Each are varying shades of brown and have slightly different body types, so view the picture to help you identify which species it is.


Photo Credit: W.C. Adlerz, UF

Beneath the grass, tunnels can be seen where mole crickets have dug. These tunnels affect the even level of the grass and damage their root structure. The damage manifests as brown patches on the surface. To diagnose the problem, mix 1.5 tablespoons of dishwashing soap in a gallon of water. Pour the gallon of mixture over a 2x2’ area of grass that looks particularly damaged. Wait about three minutes. After time has passed, you should see mole crickets coming up to the surface if you have an infestation. Two or more is cause for concern.


Photo Credit: N. Leppla, E. Buss; UF/IFAS

  • Mole Cricket Tunnels

    Slide title

    Tunnels that mole crickets have dug beneath sod.

    Button
  • Mole Cricket Damage

    Slide title

    Mole cricket damage.

    Button
Bug Blaster Plus Above/Below

How do I treat a mole cricket infestation?


The best way to treat an infestation is with an insecticide. Bug Blaster Plus Above/Below is a great insecticide to use as it targets bugs that infest both above and below the soil. Treating the problem early will help prevent further damage.

Fire Ant


How do I identify ants in my grass?


Ants are some of the most widely recognizable bugs out there. They form mounds on the surface, where they gather in large colonies underneath the ground in an intricate system of tunnels and caverns. There are many types of ants, but the ants that pose more of a nuisance to your lawn and your family are most likely going to be fire ants. Fire ants are defined by their red exterior and biting ability, which leaves a red mark and a burning sensation on the bitten individual.


Photo Credit: David Almquist, UF/IFAS

Fire Ant Mounds


If left to their devices, they can form quite large and complex mounds. They eat other kinds of lawn pests, including many types of larvae. While the ants themselves do not feed on the grass, the process of them digging their mounds and colony tunnels can damage your lawn. Your grass may become brown and thatchy as their roots become dislodged to make space for the colony.


Photo Credit: Rudolf Scheffrahn, UF


How do I treat an ant infestation?


There are several ways to treat an ant infestation. Depending on the severity of the mounds and spread of ants, different methods may be required. Thankfully, if you use any kind of general purpose granular insecticide for your lawn, it will most likely be effective at keeping those ants away. Turf Ranger II is a great broad spectrum insecticide that is effective against ants.


If the mounds are large and deep, traditional insecticides may not be the most effective. Something heavier duty and targeted may be required. That’s why we recommend using Fire Ant Control with Acephate. It is a soluble dust that you mix in water and pour directly on the mounds and areas of high ant traffic. Since it is a liquid solution, pouring a large amount on the mounds will cause it to directly seep into the colony of ants, making it more immediately effective than a granular insecticide. It is a great product for targeting specific concentrations of ants.


If the spread of fire ants across your lawn is quite severe, Over ’n Out! Fire Ant Killer Granules is the right product for your purposes. It kills ants immediately upon contact and protects your lawn for up to six months. It covers up to 5,000 sq. ft., so one bag should suffice for most residential lawns. If the infestation of ants has spread too far and too deep for traditional insecticides to handle, Over ’n Out is the best product to control these bugs.

Conclusion


These are the most common bugs that will infest your lawn. Learning how to identify them upon signs of damage is key to treating the problem quickly. If you have any questions about your lawn or the bugs that may be in it, you can call us at 813-884-3797 or email us at
info@greenthumbnursery.com. We are happy to serve you!

Reach Out to Us!

Frost on Plants
By Blake Rey January 8, 2025
All you need to know about winter frost in Florida
By Blake Rey June 19, 2024
Master List: Blue My Mind Dwarf Morning Glory High Noon Bush Daisy Vermillionaire Cuphea Truffula Gomphrena Luscious Lantana Sunstar Pentas Rockin’ Salvia Lemon Coral Sedum Meteor Shower Verbena Colorblaze Coleus Angelface Angelonia Double Up Begonia Suncredible Sunflower GoldDust Mecardonia Whirlwind Fan Flower The summer heat is here in Florida, and with it comes new challenges for your garden. Some annuals you may have planted in the spring might be struggling as the brutal heat and rain comes through. That’s why you need plants that can withstand these harsh conditions while also being easy to care for! These Proven Winners annuals and perennials are perfect for the summer weather, providing low-maintenance vibrancy to your garden. We carry these plants at our nursery, so call us for availability!
Weed Control
By Blake Rey June 7, 2024
Herbicides that will get rid of those tough-to-kill weeds without harming your grass
Hydretain Lawn Comparison
By Blake Rey May 29, 2024
Hydretain will save you headache and heartache in the dry period.
Mowing Lawn
By Blake Rey April 3, 2024
Everything you need to know for year-round lawn care
By Blake Rey March 23, 2024
The best methods to keep your palms healthy and thriving
More Posts
Share by: