Christmas tree (Douglas-fir)-Coneworm

Dioryctria spp.

Pest description and crop damage Small creamy-brown moth larvae bore into stems, especially around wounds.

Management-chemical control

Applications must be made before eggs hatch and larvae tunnel into stem. Using pyrethroid insecticides is associated with subsequent spider mite outbreaks.

  • carbaryl (Sevin and others) (Group 1A)
  • esfenvalerate (Asana XL and others) (Group 3A)-Restricted use pesticide.
  • phosmet (Imidan 70W) (Group 1B)
  • spinosad (Blackhawk, Conserve, Entrust and others) (Group 5)-Some formulations are OMRI-listed for organic production.