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Blackberry Seed Gall

Galls, abnormal plants growths caused by many agents including insects, are formed during the growing season on the buds, leaves, roots and branches of plants as a response to chemicals or physical irritation. Many of these galls serve as shelters and a source of food for their developing inhabitants.

Blackberry is host to numerous gall-making insects, including mites, midges and gall wasps, and their temporary homes (galls) are most obvious in the winter. The Blackberry Seed Gall is caused by a tiny cynipid gall wasp, Diastrophus cuscutaeformis.  A cluster of small, globular, seed-like galls within which the gall wasp larvae live are pressed together in a lump surrounding the cane.  These galls derive their species name from their resemblance to dodder (Cuscuta) fruits. Each of these 1/10th-inch diameter chambers bears a spine, and together they create a reddish-brown hairy mass.

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2 responses

  1. Alice

    The interesting life of galls. Seems like they have it all figured out.

    February 19, 2020 at 5:09 pm

  2. Janet Griffin


    February 20, 2020 at 8:27 am

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