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Abstract
Very little information has been reported on the time of pollen shedding of the many pines and firs native to Mexico and northern Central America. This kind of information is necessary for any breeding operation, and is often of considerable taxonomic and evolutionary interest as well. An example is the difference in pollination time of a month to six weeks between
Pinus radiata D. Don and
P. attenuata Lemmon, two closely related closed-cone pines native to California. This difference is a reliable means of distinguishing the two species, and is also the principal mechanism that limits natural hybridization between them.
Citation
Critchfield, William B. 1966. Phenological notes on Latin American
Pinus and
Abies. Journal of the Arnold Arboretum Vol. 47(4): p. 313-318