You’ve done all that to keep your lawn healthy and nice to look at. Your lawn, which was once green and healthy, now looks dull, thin, and patchy. What could be the cause?
If you look closely, you might see pests eating your grass. “It’s very important to find out what caused the damage,” says Shimat V. Joseph, Ph.D., an associate professor in the Department of Entomology at the University of Georgia. Different regions have different grass pests, so they need to be managed in different ways. Using the wrong insecticide can be a waste of time and money because it doesn’t deal with the root of the problem.
If you’re not sure what’s eating your lawn, contact your local university co-op extension service for help. They can give advice that is right for your area, including the best time to use treatments. A healthy lawn can deal with a few pests, but a lawn that is not getting enough water or nutrients will find it hard to cope.
If you’re worried about dealing with pests yourself, think about getting a professional lawn care service to help. If you decide to do your own pest control, read the instructions carefully to make sure you do it right. It’s important to understand which pests the product targets and how to use it correctly.
Read on to find out about common lawn pests and how to deal with them.
White grubs
White grubs are the larvae of scarab beetles like Japanese beetles, green June beetles, and chafers. Adult beetles may harm plants that are meant to be attractive, but the grubs are harmful to grass. They cause the grass to turn yellow or brown. The turf can easily come away from the soil, especially in the autumn. You might also see wildlife digging for worms in the grass.
To check for grubs, cut three sides of a one-foot square area with a shovel and roll back the sod. Look for fat, C-shaped grubs. They should be white to dirty-white on the body, and brownish on the head and legs.
These beetles live for about a year. In the early summer, the adult beetles lay their eggs in the soil. The hatched grubs eat the roots of grass until winter, when they dig deep into the soil. The following spring, they come back up to the surface and start eating again, and then they turn into adult beetles.
Mature grubs can be dealt with using curative products in summer and autumn, but spring is the best time to use preventive insecticides. You could try using products that contain chlorantraniliprole, imidacloprid, clothianidin, or thiamethoxam.
To fight chinch bugs, Joseph suggests using amethoxam in the spring, following the instructions on the label. He says not to use bacterial milky spore products, which have not worked. Also, traps do not work well to get rid of adult beetles and they might even bring more beetles to the area.
Chinch bugs have mouthparts that pierce and suck, and they use these to inject toxic saliva into grass stems, feeding on the plant’s juices. They do really well in dry conditions, and usually appear after two to three weeks without rain. Adult chinch bugs are 1/6-inch long. They have black bodies, black-and-white wings, and reddish legs. Young chinch bugs are orange-ish with a white stripe and move quickly. They can kill grass very quickly. The first signs of damage to your lawn may be reddish or yellowish patches, especially in sunny areas.
To detect chinch bugs, Joseph suggests using a large metal can with soapy water. If you see chinch bugs, they will float to the surface. If you have 25 to 30 bugs in a square foot, you need to use pesticides. Products with imidacloprid or bifenthrin are good for this.
Grass mites, which are common on warm-season grasses, can cause a lot of damage, especially in spring and fall. These tiny pests drink the sap from plants and can make unusual patterns of damage on grass. To identify a plant positively, you need to get help from a local university’s cooperative service. Some types of grass mite don’t have any registered chemicals that can kill them. But products with abamectin or spiroteramat might work. Other things you can do to help are to mow the grass at the right height and remove any infected clippings.
Billbugs have long, bill-like snouts. They can be destructive pests in turfgrass. Adult billbugs can be tricky to spot in the grass, but they often gather on driveways and pavements as the temperature rises in spring. Larvae, which look like white grubs without legs, eat inside grass stems after the females lay their eggs in the plant tissue.
To stop billbugs from damaging your lawn, which eat the grass roots and leave brown patches in summer, Joseph suggests doing a “tug test”. This is a test to check for these pests. If grass comes away easily and stems break without effort, there are likely to be billbugs. Use a white grub product that contains active ingredients like chlorantraniliprole, imidacloprid, clothianidin, or thiamethoxam. Follow the instructions on the label.
Scales and mealybugs are sucking pests that can harm warm-season grasses like bermudagrass. Scales have a hard, waxy coating, while mealybugs have a white, cottony appearance. At first, the grass might look like it needs water or fertiliser, but if you don’t check first, it might start to turn yellow or brown. To deal with this, first find out what the pest is, then use the right product to get rid of it. If you want to kill more insects, use chemicals that are put directly onto the plants. These chemicals can be called imidacloprid, clothianidin or thiamethoxam.
Fall armyworms are a problem that can happen on and off throughout the summer and autumn, and they can destroy grass. After female moths lay eggs, the baby caterpillars quickly grow into green or black caterpillars. These leave brown marks on the grass, which look like they are caused by lack of rain. Look out for egg masses and get rid of them quickly. Also, look out for caterpillars and act fast. Use products containing chlorantraniliprole or bifenthrin, following the instructions on the label.
