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Filtering by: Subject Psylla -- Oregon Remove constraint Subject: Psylla -- Oregon Creator Westigard, Peter H. Remove constraint Creator: Westigard, Peter H.

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  • The pear psylla in Oregon

    Creator:
    Westigard, Peter H. and Zwick, Robert Ward, 1922-
    Abstract:
    Since its discovery in Oregon in 1946, the pear psylla, Psylla pyricola Forster, has become the most serious insect pest of pear. Damage to pear trees include the transmission of pear decline disease which has caused losses of trees, injection of a phytotoxic toxin resulting in tree shock and injury,...
    Resource Type:
    Technical Report
    Full Text:
    Pear Psylla in Oregon Technical Bulletin 122 AGRICULTURAL EXPERIMENT STATION Oregon State University