As our east Texas temperatures continue to rise, the likelihood for the appearance of commonly found pests in turfgrass also rises. Some pests to look for along with descriptions of possible damage to the turf, and a description of the pests themselves are included below.

Armyworms feed mostly on Bermuda, rye and fescue grasses causing considerable tissue damage in the process. Injury to turfgrass is often seen on golf courses, athletic fields, and lawns, but agricultural crops and garden vegetables can be added to the mix when other food sources are not available. It is not uncommon for armyworms to eat their way through a football field in 2 or 3 days. Their name comes from the side by side formation as they move across a feeding area.

The life cycle of the armyworm goes through 4 stages: egg, larva, pupa, and the adult moth. It is the late stage larvae that cause the most damage to turf. The caterpillar larvae can be identified by its brown, to gray or green coloring with a distinguishing white inverted Y between the eyes.

Although they usually feed through the day, the larvae are most active in early morning and late evening. Initially, evidence of damage can be found on blade tips, where the caterpillars eat the plant tissue causing the ends to become transparent.

Damage will resemble drought stress at onset, but if left unchecked, complete foliage loss can occur. Early detection is crucial due to rapid feeding and devastating destruction. It is important to treat as soon as possible.

Lawn grasses, golf courses and athletic fields need to beware of sod webworms in summer heat. These pests feed primarily at night or on cloudy days making it difficult for detection during daylight hours. However, in heavily populated areas of infestation, indicators of damage can be identified by the shorter turfgrass whereas, healthy grasses will be notably taller.

Like the armyworm, sod webworms complete all stages of metamorphosis during development. It is the newly hatched larvae that feed on turfgrass. They are typically an almost transparent greenish color with small dark spots on each body segment and a dark yellow to brown head. To detect worms in a given area, sprinkling the turf with a water and liquid dishwashing soap solution will force the caterpillars to climb up on top of grass blades.

Infested turf areas are usually spotty in appearance but will enlarge as the worms search for more food. Injured blades appear ragged edged due to larval chewing. It is important to treat affected areas at first detection to curtail further injury to the lawn.

Adult chinch bugs are approximately 3/16 – inch long with black bodies and white wings that have a single black spot along the outer edge. Females lay single eggs either on the leaf blade or in the soil near host plants. Orange colored nymphs, sporting a white band running across their back, will emerge from the eggs.

St. Augustine grass is the primary target for the southern chinch bugs. Both nymphs and adults have sucking mouth parts to extract sap from the base of leaf blades and stolons. At the same time, they are injecting a toxin which prevents the movement of water through the plant.

Turfgrass injured by the chinch bug activity usually appears drought or heat stressed. Areas may initially be localized but expand as populations of bugs increase. Unlike the circular damage caused by brown patch fungus, chinch bug destruction exhibits irregular-shaped areas of infestation.

Keeping lawn thatch to a minimum reduces a desirable food source for these pests and goes a long way in managing chinch bug populations. Proper mowing practices, core aeration with the addition of a topdressing and appropriate watering for current weather conditions also aid in reducing the chance for an outbreak.

(More information on chinch bugs can be found in the July 2019 newsletter)