Watercress-Aphid

Includes bean aphid (Aphis fabae)

Pest description and crop damage The bean aphid is dark olive green to black with light-color legs. It is usually more of an early-year pest. Aphids damage plants by sucking plant sap, which causes heavily infested leaves to curl and stunts plants; excreting honeydew, which causes sticky, shiny leaves to turn black because of a sooty-mold fungus growth; and spreading plant diseases. Infestations frequently are localized; heavily infested leaves curl down.

Management-chemical control: HOME USE

Apply to both tops and undersides of leaves.

  • azadirachtin (neem extract)-Some formulations are OMRI-listed for organic use.
  • imidacloprid
  • kaolin-Applied as a spray to foliage, it acts as a repellent to some insect pests. Some formulations are OMRI-listed for organic use.
  • malathion
  • permethrin
  • plant essential oils (rosemary, etc.)-Some formulations are OMRI-listed for organic use.
  • pyrethrins-Some formulations are OMRI-listed for organic use.
  • spinosad

Management-chemical control: COMMERCIAL USE

  • imidacloprid (Admire) at 0.16 to 0.38 lb ai/a soil or 0.047 lb ai/a foliar. PHI 21 days soil; 7 days foliar. REI 12 hr. Do not exceed 0.38 lb ai/a soil or 0.24 lb ai/a foliar per season.
  • imidacloprid (Provado, Prey) at 0.047 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 5 days. Do not exceed 0.24 lb ai/a per season.
  • insecticidal soap (M-Pede) at 1% to 2% solution. See label for gal/a. PHI 0 days. REI 12 hr.
  • malathion (Malathion 8) at 1 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 3 days. Limit 5 treatments.