Spraying for Douglas-fir needle midges in Christmas tree plantations
By: Ben Simko.
Edition: Rev. Sept. 1982.
Series: FS / Oregon State University Extension Service -- 164.; Fact sheet (Oregon State University. Extension Service) -- 164.
Publisher: Extension Service, Oregon State University
Published: 1982
Place of publication: Corvallis, Or
Language: eng
Subjects: Contarinia -- Northwest, Pacific.; Douglas fir -- Diseases and pests -- Northwest, Pacific.; Christmas trees -- Diseases and pests -- Northwest, Pacific.
Notes: Title from caption.