Northern red oak (Quercus rubra L. syn. Q. borealis F. Michx.) is a valuable broadleaved tree species originating from the eastern half of the USA and Canada. It was introduced to Europe in 1691 and currently covers over 350 000 ha, being found all over the continent, except the coldest part of Scandinavia. It is a fast-growing and valuable broadleaved tree due to its ecological characteristics, good wood properties and high economic value. Northern red oak prefers deep, loose, moderately humid and acid soils, without compact horizons and of at least moderate fertility. It does not grow well on dry, calcareous soils as well as waterlogged or poorly drained soils. It is either naturally regenerated using a group shelterwood system or planted using seedlings of European provenance, collected in certified seed stands. As northern red oak is light-demanding, its management should be %dynamic% and includes heavy interventions (cleaning%respacing and thinning from above), in order to minimize crown competition between the final crop trees. These should produce large diameter trees for valuable end uses (e.g. veneer, solid furniture, lumber, etc.) within a rotation period generally of 80%100 years. The necessity for pruning (both formative and high) depends on the stand stocking at establishment, the subsequent silvicultural interventions as well as the occurrence of forking. The adaptation potential of northern red oak to predicted climate change, especially drought, seems to be...
COBISS.SI-ID: 5197478
The management of tree species non-native to Republic of Croatia has a certain tradition within Croatian forest management practice; nowadays, their potential should be regarded and re-evaluated in the new frame of climate changes and growing society demands for forest products and services. This paper is a contribution to non-native tree species (NNTS) introduction and use in Croatia, aiming at providing state of the art of NNTS as well as overview of studies and examples of possible management opportunities. Because of the complexity of the matter and growing need to further investigate risks and challenges of NNTS in Croatia, authors have continued their research and will publish the results in a separate paper. Amount of the area occupied by NNTS forest cultures point to the conclusion that the use of these tree species in forest practice is not reached by far and the nursery production does not back up the need for NNTS use. Paper also provides a comprehensive overwiev of different aspects and benefits of the use of NNTS in Croatia. For example, increased wood production and non-wood forest products; production of high quality timber in short%time periods; use of fast-growing tree species for bioenergy production in higher proportion and enhancement of ecosystem services. Increase of stability and adaptive capacity of forest stands by the use of NNTS is highlighted as new silvicultural option for facing climate change.
COBISS.SI-ID: 5182630
The growth of seven exotic true fir (Abies) species and native Abies alba 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 A. alba and A. cephalonica appears rather heterogeneous in its phenotypic behavior. A. alba provenances show superiority, but also a high differentiation. Productivity of provenances of A. cephalonica fall behind A. alba; however A. cilicica and A. pinsapo provenances have shown total mortality. The high potential of A. grandis is confirmed by outstanding growth; provenances from the coastal plain in Washington State performed best. A. procera grows slower than A. grandis, but still faster than A. alba 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.
COBISS.SI-ID: 5257638