The causes of reduced seed yield in four Douglas fir (Pseudotsuga menziesii Mirb. Franco) trees at the Dewdney Seed Orchard in 1986 were found to be inadequate pollination (30%), low pollen vigour or viability (14%), embryo abortion (14%) and early ovule abortion (5%). The average seed efficiency (+ s.e.) for the four trees was 40 (+ 7). Conelet abortion in the four trees, averaged 43%, ranging from 20 to 64% per tree. Recommendations for increasing seed yield are discussed.
FRDA Research Report 057 (564 KB)
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Updated July 24, 2015