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Abstract
Hybrids between
Abies procera Rehd., and
Abies magnifica A. Murr., made reciprocally at Marys Peak near Corvallis, Oreg., and near Placerville, Calif., suggest that no significant genetic barriers prevent crossing of the two species where ranges overlap. Hence, maintenance of species differences must be looked for in other factors. Cotyledon number, a very early expressed trait, was used to verify that recently germinated seedlings were true hybrids.
A. magnifica cotyledons averaged nine,
A. procera five, and the hybrids at both locations seven, with each seedling population statistically distinct.
Citation
Silen, Roy R.; Critchfield, William B.; Franklin, Jerry F. 1965. Early verification of a hybrid between noble and California red firs. Silvae Genetica 12, Heft 6: p. 187-191