Exotic Abies Species in Czech Provenance Trials: Assessment after Four Decades

The growth of seven exotic true fir species and native have been compared in three provenance trials in the Czech Republic, at the relatively advanced ages of 44, 38, and 35 years respectively. A clear differentiation is observable between the species. The closely related species group of and appears rather heterogeneous in its phenotypic behavior. provenances show superiority, but also a high differentiation. Productivity of provenances of fall behind however and provenances have shown total mortality. The high potential of is confirmed by outstanding growth; provenances from the coastal plain in Washington State performed best. grows slower than but still faster than provenances. Health risks, extreme ecologic distances of transfer, trend shifts of growth rate, and rank change with age are uncertainties that require necessary caution when selecting provenances for importation. In recent years, public and institutional perceptions concerning the introduction of non-native tree species and provenances has shifted, and the practice is no longer seen as necessarily inappropriate.