Joanne Whalen, Extension IPM Specialist; jwhalen@udel.edu
Cabbage
Begin scouting fields for imported cabbage worm and diamondback larvae. As a general guideline, a treatment is recommended if you find 5% of the plants infested with larvae. If both insect species are present, Avaunt, Coragen the Bt insecticides, Proclaim, Rimon, Spintor, Synapse or Radiant have provided control.
Peas
Be sure to sample peas for pea aphids as soon as small seedlings emerge. On small plants, you should sample for aphids by counting the number of aphids on 10 plants in 10 locations throughout a field. On larger plants, take 10 sweeps in 10 locations. As a general guideline, a treatment is recommended if you find 5-10 aphids per plant or 50 or more aphids per sweep. The recent cooler temperatures will slow the activity of beneficial insects but favors the development of pea aphid populations.