Surface Feeders - Black Cutworm (BCW)

BLACK CUTWORM (BCW)
aka: Greasy Cutworm
scientific name: Agriotis ipsilon Similar species: Variegated cutworm, Bronzed cutworm

FIELD KEYS
Hosts: bentgrass, ryegrass, and most other grasses
Site symptoms: Small roughly circular areas of eaten turf often surrounding an aeration hole or tunnel or cavity dug in soil or thatch.
Plant symptoms: Larvae eat plants at or near the soil line.
Site keys: A problem pest on golf greens and tees and other highly maintained bentgrass locations.

SPECIMEN ID
Larvae range from 1/4 inch translucent first instars to large, 2-inch long, dull gray to black stripped caterpillars that will roll into a coil when disturbed. Adults are gray moths with black wing markings and a 1 1/2 inch wing span.

SCOUTING TIPS
Look for small circular or depressed areas around aeration holes or shallow dug tunnels in soil or thatch. Mature larvae are night feeders that can be seen with a light or can be dislodged from their holes or tunnels during daylight with a soap or insecticidal flush. BCWs can produce from 2 to 6 generations per year de-pending on the region. Look for active larger larvae feeding on turf at night. Monitor larval populations with flushes and be aware that BCW is a pest on many agriculture crops so reinfesta-tion can occur rapidly Look for adult females feeding on neigh-boring flowering shrubs or trees at night.

CONTROL STRATEGIES
Cultural: If BCWs are using aeration holes as hiding places, delay aeration practices to less favorable periods after active larval growth stages or try backfilling holes with topdressing.

Chemical: In most areas, where BCWs are a consistent problem in turf, consider beginning control applications when concentra-tions of larger immatures reach one per three square feet. Use a soap flush to monitor for larvae every week. Treat with insecticide as soon as several small larvae are found. On golf courses, also treat 15-30 feet around greens and tees to prevent reinvasion. Resample in 40-50 days.

Growth stages: egg - caterpillar (several instars)* - pupa - adult
* - treatable stages

Life cycle: 1 year cycle (multiple generations)
Sequence: larva - adult - egg - pupa - adult - egg - larva