Small grain-Leafminer

Phytomyza nigra

Pest description and crop damage Larvae mine the lower leaves of fall-seeded wheat, barley, and rye during the spring following seeding. New spring growth appears to mask injury these larvae may cause. The larvae are heavily parasitized by other insects, and this may aid in keeping this insect at relatively low numbers.

Management-chemical control

Insecticide control is rarely needed.

Foliar sprays

  • azadirachtin (Aza-Direct, Ecozin 3EC) at 0.0125 to 0.043 lb ai/A. PHI 0 day. REI 4 hr. Retreatment interval 7 days. Best results can be obtained following 2-3 applications made at 7-10 day intervals. Some formulations are OMRI-listed for organic use.
  • pyrethrin-There are several pesticides containing various amounts of pyrethrins. Check each label for the use and amount needed. Some formulations are OMRI-listed for organic use.