Symptoms
Entry holes with sawdust-like frass on stalk. Dead heart in young plants. Stalk tunneling causes stalk breakage and lodging. Larvae also bore into ears causing grain damage.
Prevention
Plant resistant varieties where available. Destroy crop residue after harvest. Use pheromone traps for adult monitoring. Plant at uniform times to reduce inter-crop larval movement.
Treatment
Organic
Apply Trichogramma egg parasitoids. Spray Bacillus thuringiensis (Bt) targeting young larvae at whorl stage. Apply spinosad at early instar.
Chemical (last resort)
Apply chlorpyrifos or carbofuran granules to plant whorl at early infestation. Systemic insecticides applied at egg hatch are most effective. Observe PHI.
Affects 1 crop
Sources
MARDI Corn Production Guide; DOA IPM Manual