2024, Zeidler, Aleš, Borůvka, Vlastimil, Brabec, Pavel, Tomczak, Karol, Bedřich, Jakub, Vacek, Zdeněk, Cukor, Jan, Vacek, Stanislav

European forests are facing ongoing climate change, and certain tree species are being critically impacted. The Norway spruce (Picea abies (L.) Karst.) is one of the most sensitive species to climate fluctuations, a fact manifesting itself through massive dieback resulting in a lack of high-quality timber and timber market destabilization. Therefore, the possibility of wood substitution with non-native spruce species, namely, black spruce (Picea mariana (Mill.) Britt., Sterns, et Poggenburg), Serbian spruce (Picea omorika (Pančić) Purk.), and blue spruce (Picea pungens Engelm.), under the specific conditions of forest reclamations with great potential for future afforestation was tested. Wood density, modulus of rupture, and modulus of elasticity were used to evaluate wood quality in comparison with native Norway spruce. The results confirmed that only the Serbian spruce reached the quality of Norway spruce and even exceeded it in terms of wood density (P. omorika 525 kg·m−3 vs. P. abies 517 kg·m−3) and exhibited comparable parameters with regard to other properties. The density of the other species was significantly lower for blue spruce (476 kg·m−3) and black spruce (468 kg·m−3). A similar trend was found for other wood parameters, which confirmed that Norway spruce quality was nearly comparable with that of Serbian spruce. On the other hand, black spruce and blue spruce did not match the quality of Norway spruce. The within-stem variability of the properties tested was low for all the spruce species examined. In conclusion, the Serbian spruce showed great potential for future usage in forest management and is one of the possible methods of Norway spruce replacement in times of unprecedented forest disturbances under the effects of global climate change.

2025, Tomczak, Karol, Vacek, Zdeněk, Cukor, Jan, Vacek, Stanislav, Bažant, Václav, Zeidler, Aleš, Trojan, Václav, Gallo, Josef, Černý, Jakub

Ponderosa pine (Pinus ponderosa) is one of the most valuable American pines growing naturally in the western and Pacific states of Arizona and California. Based on previously published research, its ecological valence makes this species suitable for introduction worldwide, including Europe. In Central Europe, climate change—the primary cause of significant dieback of native tree species, such as Norway spruce and Scots pine—has increased the need to explore new methods to ensure forest stand sustainability. Introducing previously overlooked tree species, such as ponderosa pine could help address this challenge. We reviewed 229 research sources to analyze P. ponderosa’s potential for utilization in new areas. The existing research from its native distribution range indicates ecological plasticity and strong resistance to drought and climatic extremes. Production parameters were evaluated in young European forest stands with a stand volume of 430 m3⋅ha–1 at the age of 45, pointing toward a promising use in the forestry sector. In European forestry, ponderosa pine’s importance could grow due to its adaptability to warm and dry climates and tolerance of diverse soil conditions. Moreover, the extraordinary quality and texture of the wood, as well as ponderosa’s biodiversity and ornamental functions, make the species destined to become part of future landscapes and forest ecosystems of Central Europe under changed climatic conditions. However, we also see challenges and scientific gaps associated with the management of ponderosa pine and its introduction to mixtures with native tree species without prior verification and silviculture recommendations.