Life History and Habits of a Midge, Contarinia washingtonensis Johnson (Diptera: Cecidomyiidae), in Douglas-fir Cones

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Abstract
The midge Contarinia washnigtonensis Johnson is capable of causing serious seed loss in Douglas-fir in British Columbia, Washington and Oregon. The female lays its eggs from late May until early July in the young cones. When the eggs hatch larvae feed in the cone scales, sometimes causing direct damage to seeds and often killing scales before cone maturity. When larvae have completed feeding they leave the cone scales in late summer and autumn to drop to the ground where they spin cocoons and remain overwinter in the litter.