Popis: |
Pinus contorta Douglas ex Loudon var. yukonensis W. L Strong (Yukon pine), a new variety, is described from south–central Yukon, Canada. It is a stout tree with long lower branches, often with paired lower and forked upper stems, and weakly platy to smooth gray bark on the lower stem, when < 70 years old; with bark on the lower stem becoming furrowed and platy on older trees. This contrasts with the narrow columnar habit, simple stem, and scaly bark associated with the more common inland var. latifolia. In several respects, var. yukonensis is more similar to var. contorta (a coastal variant), although occupying a different ecological regime and spatially disjunct (i.e., a high latitude and high elevation variant). Variety yukonensis may represent the taxon alluded to in previous leaf oil terpene and genetic studies, and a possible Beringian survivor. |