Turf Destroying Insects

Ewww a bug!

You may have noticed that Florida has its fair share of bugs. They all have their food preferences; some like to feast on wood, some on humans and animals but the ones we will be going over in this article are those that have a target set on your grass! Most insect turf problems we experience in Northwest Florida are caused by mole crickets, chinch bugs or sod webworms.

Mole crickets are subterranean insects about 2 inches long with a face only a mother could love! While they are well known for eating turf grass, they are happy to include the vegetables from your garden in their diet! Vegetable damage usually appears above ground as wilted and drought stressed leaves while their roots are being eaten. Seedlings are usually taken underground to be eaten entirely. Turf damage from mole crickets can be recognized by patches of dead grass that have no root structure left. Damaged grass can be lifted off the soil with no resistance because all the roots are gone. Tunneling activity can also be observed on top of the soil where mole crickets are active. This tunneling activity produces raised trails in the soil about the size of your finger and causes the ground to be very soft. Mole crickets can fly and migrate from place to place. If you own a pool, you may find mole crickets in your pool filter. Sometimes they find themselves caught in the pool after carelessly flying around. They are nocturnal and are attracted to light which is why you see them on your porch at night! If you live near a golf course you have a good chance of mole cricket activity in your lawn because golf courses spare no expense on mole cricket treatment. These treatments drive the insects away from the greens into the surrounding yards. A soap flush can verify the presence of mole crickets in a particular area. To prepare a soap flush, mix a few ounces of liquid Joy dish soap in 5 gallons of water and dump it into a 2-foot by 2-foot area. If mole crickets are present, they will scurry to the surface. Mole crickets have a one-year life cycle that begins in early spring. Male mole crickets can be heard serenading in the moonlight for find a mate in early spring. Fertilized eggs hatch and by May they become mature. They are easier to control though treatments in May before they become mature. When treating the lawn with an insecticide for mole crickets, the key is to make sure the treatment is watered in very well after it is applied so that it will reach the root zone of the grass where the pests live.

Chinch bugs typically only affect St Augustine grass. The peak time for chinch bug activity along the Emerald Coast is between April and October. When mature, chinch bugs are tiny about 1/8-inch-long bugs that are black with white dots on their back. It is likely to find them in a warm sunny location of the lawn where they live in the thatch area of the grass, making them difficult to find. They feed on the grass by sucking the juice out of the stems. Grass affected by chinch bugs appears to be drought-stressed and when severely damaged gets a “hay” like look to it. Chinch bugs work together in an area of the lawn and move along as a group to feed causing the damaged areas to grow. One way to detect the presence of chinch bugs in the lawn is to take a hollow cylinder, such as an empty coffee can with both ends removed, place the can over an affected area and fill the can with water. If there are chinch bugs present, they will float to the top. Chinch bugs should be treated with an insecticide but not watered in for a day or two unless using a dry granular insecticide that requires water for activation. Repeat applications are frequently necessary because it is hard for the treatment to the insects when they are buried in thatch.

Sod webworms are destructive little green caterpillars and are about ¼ inch long and feed on the grass blades of all types of warm season grasses. Here in Northwest Florida, our winters get cold enough for their activity to cease. However, once the temperatures start warming up, typically late April, early May they start to become active again and continue through October. They will initially appear in the shady areas of your lawn, resting in the trees and the bushes as small light brown moths. The moths themselves are not destructive and are not always an indication that your lawn will be on their menu. The moths fly around at night to find the best place to lay their eggs. Once the larvae have emerged from the eggs, they start to feast on turf grass through the night. Individual damaged blades will either appear to be chewed on or look translucent in areas where the insect has stripped the surface of the blade away and left only the skeleton. This damage makes it seem as though the lawn has been mowed down very short but only in some areas. You may be able to find sod web worms in the grass by going over to the damaged area and pulling apart the grass blades. The best time to treat sod webworms is during the early larvae stage; control is not as affective in the adult moth stage. Sod webworms can be treated with insecticides and the treatment should be kept dry and not washed off the grass blades. Sod webworms have a 14-day lifecycle so retreatment may be necessary as new generations of larvae are hatched. Depending on the severity of the infestation, these pests can literally destroy a lawn overnight. Therefore, once their presence is confirmed, immediate treatment should be performed. If damage is minimal the grass can recover.

Keeping an eye on your lawn during the growing season will help you stay on top of insect activity. It’s also a nice way to get some fresh air at the same time!