Is your turf issue drought stress or chinch bug damage?

Without bias Chinch bugs (often mistaken for big-eye bugs as seen on the right) are equal-opportunity turfgrass attackers, targeting both cool- and warm-season grasses. (Photo: North Carolina State University)

Chinch bugs can be a difficult pest for lawn care operators to identify and control. Closely mimicking drought damage, these pests cause turf to turn yellow and thin, transforming into dry patches if left untreated.

Chinch bugs pierce the turfgrass blades and suck fluid from the plant. As they feed, they also secrete toxins inside the turfgrass that disrupt the water and nutrient movement within the plant. This condition causes the turf to yellow and wilt, which is why chinch bug damage is often misidentified as drought stress.

Lawn care professionals share the best ways to tackle chinch bugs and treat the damage they cause to turfgrass.

Chinch bug 411

“Both cool- and warm-season turf can be affected by chinch bugs,” says Bret Corbett, director of technical services with Prime Source. “In the Southeast, the Southern chinch bug can affect almost all warm-season varieties, but St. Augustine is the most common turf type to be associated with extensive damage.”

For cool-season turf, hairy chinch bug is most common. It’s found in Kentucky bluegrass, fescues and ryegrasses, according to Corbett.

Brian Mount, FMC technical service manager for insecticides, says drought or otherwise stressed turfgrasses will be more susceptible to chinch bug attacks.

“A healthy lawn is a great defense against attack from insects and diseases,” Mount says. “It is also worth noting that chinch bugs can attack totally healthy turfgrass as it would represent a good source of food.”

Signs of damage

The most telling sign of chinch bug damage is irregular yellow patches of turf, says Mount.

“These patchy areas can turn reddish brown and eventually die while the chinch bugs move outward into healthy turf,” he says. “A yellow halo around the damaged area is typical of a chinch bug infestation.”

Todd Lowe, technical services manager at Envu Green Solutions, notes that chinch bugs appear more active each spring and continue throughout the hot summer months. Areas experiencing drought will have greater chinch bug damage at the time, he adds.

“Hopefully, homeowner irrigation systems can keep the turf from dying off completely before effective programs can be implemented,” Lowe says.

Locating and eradicating

Early detection is key because early life stages of the chinch bug are easier to control than later stages, according to Mount.

Lowe says LCOs should use the tin can test to scout for pests. This method involves lawn care operators taking a coffee can or similar device, and cutting both ends and inserting it into the upper soil of the lawn. Professionals then saturate the soil with a hose until insects and clipping debris float upward.

Corbett offers another way for professionals to identify the pest.

“Pulling back the turf adjunct to yellow areas is a great way to scout for these pests,” he says. “Chinch bugs can usually be seen easily if they are present.”

Research from North Carolina State University lists the threshold as 20 to 25 chinch bugs per square foot.

Once LCOs determine insecticide treatments are necessary, experts say they can — and should — deploy several active ingredients to control the pest.

“Products that are used for control of chinch bugs include products that contain the active ingredients acephate, chlorantraniliprole or clothianidin along with many different pyrethroids,” he says. “The bioinsecticide Crescendo also provides great knockdown.”

Mount adds, “In the South, where treatments occur year-round, it is important to rotate active ingredients as chinch bugs can quickly develop insecticide resistance.”

For more on chinch bugs, read “Chinch bugs be gone.“