Chinch bugs in Southeast Lawns

Print page

Chinch bugs are piercing sucking insects that damage turf with their salivary toxins and sucking plant juices from turfgrass growing points (crowns). They are a primary pest of St. Augustinegrass lawns (southern chinch bug [SCB]).

Identification

SCB nymphs are bright reddish orange, about 1/32” long, with a white band across the abdomen
SCB are tiny insects, about 1/6” long and about 1/32” wide, with adults appearing grayish black and with or without wings
All stages of SCB damage turf by piercing and sucking plant parts
Flotation is the best way to detect chinch bugs: cut both ends off of a coffee can or similar container, push the edge of the can into the soil past the thatch, and then flood the can to the brim and refill as needed

Damage
- Early damage appears as patchy areas of yellowing grass that rapidly browns and dies if the pest is left uncontrolled
- Symptoms resemble drought stress, and if areas are misdiagnosed, damage expands rapidly as chinch bugs move from dying grass to healthier areas
Life cycle

Adults overwinter in northern Florida and egg-laying begins in late spring
A new generation (egg to egg) requires about 13 weeks at 70oF and only 5 weeks at 83oF
Largest surge of newly hatched nymphs is generally in early spring when a new generation can be completed in five weeks
Populations can grow quickly with peak nymph emergence from late June through October and peak turf damage coinciding with these populations, especially with stress from hot dry weather
SCB can have seven or more generations in south Florida
Only three to four generations of SCB are common farther north in Florida and along the Gulf Coast

Cultural control

Maintaining a healthy turf is critical for mitigating damage
Limit thatch – SCB damage is more common in lawns with heavy thatch
Fertilize and irrigate judiciously – over-fertilization and/or over-irrigation creates a lush lawn prone to SCB as well as thatch buildup

Insecticidal control
- Barricor^® (deltamethrin), IRAC Group 3A – Solid particle formulation, Type II pyrethroid
  - Barricor (0.5 fl oz/1,000 ft2) – when pest pressure is slight to moderate, Barricor alone provides up to 8 weeks of SCB control
  - Barricor + Merit^® provides two active ingredients and is therefore more effective with higher populations and also reduces the chances of developing insecticide resistance
- Tetrino^® (tetraniliprole), IRAC Group 28 –diamide insecticide introduced in 2021 that controls several lawn pests, including chinch bugs, grubs, billbugs and sod webworms
  - Tetrino (0.73 fl oz/1,000 ft2) – when pest pressure is slight to moderate, Tetrino alone provides up to 6 weeks of SCB control
  - Barricor + Tetrino increases efficacy over single insecticides especially with higher populations and also reduces chances of insecticide resistance from developing
- Merit (imidacloprid), IRAC Group 4A insecticide – A cornerstone of current southern chinch bug programs
  - Alone, Merit provides chinch bug suppression but when combined with Barricor, Merit provide longer residual and reduced pyrethroid use
Season-long programs – In areas such as Florida and the gulf coast states, where multiple SCB generations occur, insecticides are applied consecutively from spring through early fall: