The introduction of tree species raises the question of whether they find suitable conditions in their secondary range and whether they can successfully adapt to the new conditions in the context of an unstable climate. Stem secondary growth of trees and the changes in xylem cell structure make it possible to trace the adaptation process to the new climate on an inter- and intra-seasonal scale. The objective of this study was to determine whether the seven non-native conifer species in Central Europe differ in climate sensitivity and to what extent late frost and spring-summer drought can influence xylem changes. In our study, we investigated the growth pattern and xylem cell structure modifications of seven introduced conifer species Pseudotsuga menziesii, Pinus strobus, Tsuga canadensis, Abies grandis, Pinus banksiana, Pinus rigida, Pinus nigra, growing under uniform conditions in Poland. To determine species-specific temporal variations in climate sensitivity, we used stationary and non-stationary correlations of ring width with daily climate variables: mean, minimum, and maximum temperatures, precipitation sum, and SPEI, supported by a pointer-year analysis. Changes in xylem structure (frost rings and intra-annual density fluctuations) were analyzed using light and fluorescence microscopy. Warming of the winter-spring period benefits both southern European and North American introduced conifers, as reflected in the extended responsiveness period. However, as the growing season warms and the risk of late frosts increases, the potential for acclimatization of non-native species decreases, especially with respect to their juvenile growth phase. Negative precipitation and evapotranspiration balance at spring-summer period can lead to reduced growth and anomalies in earlywood xylem structure, commonly referred to as intra annual density fluctuations. P. strobus, the species that loses both frost-induced cambium damage and drought-induced xylem anomalies in summer is the fastest growing non-native species, along with P. menziesii. Although the results presented here show the potential and the limitations in the acclimatization of coniferous species, the obvious limitations related to local environmental conditions and the different ages of the trees make us cautious in generalizing the conclusions. Therefore, we call for the creation of a pan-European dendro-network of sites of non-native coniferous species.

The use of truffles in Poland has a long tradition, yet due to some historical aspects, this knowledge was lost. Currently, truffles and truffle orchards are again receiving attention, and thanks to, e.g., historical data, they have solid foundations to be established. Publications relating to truffles between 1661 and 2017 were searched for in international and national databases, such as the database of PhD theses, Google Scholar, and catalogues of the National Library of Poland, the Jagiellonian Digital Library, the University Library of J. Giedroyc in Bialystok and the Lower Silesian Digital Library (DBC). A very meticulous survey of the literature on truffles showed that truffles have been known since at least 1661. In the 18th century, the fungi were considered a non-timber forest product. It is interesting to mention the impact of Polish Count Michał Jan Borch in understanding the nature of truffles. The whitish truffle (Tuber borchii) is named after him. The greatest number of publications regarding truffles can be observed at the first half of the 19th and 20th centuries. The fungi were present not only in cookbooks but also in scientific literature, and aspects of their ecology and medicinal use are considered. The “dark ages” for truffles, mainly for social reasons, occurred after the Second World War. In tough times, when Poland was under Soviet communist control (1945–1989), truffles as a luxurious product have been completely forgotten. However, at the end of the 20th century, truffles started receiving attention in Polish society. Yet, the real awakening began in the first decade of the twenty-first century when the first truffle orchards were established. One of them has already produced the first fruit bodies of summer truffle (Tuber aestivum). Truffles have been present in Polish culture for centuries. Their renaissance indicates the need for fostering sustainable agroforestry-centred initiatives aimed at helping truffle growers in growing the precious fungi and thus meeting market demands.

The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this study, we investigated growth and survival of Df seed sources to fill a knowledge gap regarding recommendations for the future use of Df provenances in Poland. Our experimental test site represents the most continental climate among all Df trials installed in the IUFRO 1966–67 test series in Europe. At this unique single site, we evaluated the performance of 46 Df provenances from North America, and nine local landraces of unknown origin. Repeated measurements of tree diameter, height, and volume were analysed, to age 48, representing integrated responses to geographic and climatic conditions. Significant variation in survival and productivity-related traits were found, with the interior Df provenances performing best, in contrast to previous European reports. The higher survivability and volume of the interior provenances resulted from their superior frost resistance. The low precipitation seasonality at the location of seed origin provided an additional advantage to the trees at the test site. Geographic and climatic factors of seed origin explained most of the variation in productivity (77 and 64%, respectively). The tested landraces exhibited diverse performance, implying that naturalized local seed sources in Poland need improvement and perhaps enrichment with new genetic material from North America, while considering geography and climate. Assisted migration programs should consider the limitations imposed by both frost and drought events in guiding future Df selections for continental climates. Further field testing, early greenhouse screening and DNA testing are also recommended.

Climate is a primary, but non‐stationary, driver of tree growth. Climate change is altering the sensitivity of forest growth to water availability and temperature over time. It is considered that pedunculate oak ( Quercus robur L.) will cope with the changing climatic conditions in Europe in the near future. However, while species distribution models project expansion zones, they also identify reductions in occurrence at the dry and warm distribution margins. Whereas species distribution models primarily rely on occurrence data, tree rings—given their long‐term perspective and their use in empirical models—can provide a mechanistic view of forest growth dynamics, including temporally changing climate responses. Increased climate sensitivity and growth synchrony are key dendroecological indicators of tree stress. Here, we used an unprecedented network of 150 Q. robur sites (over 3300 trees), covering the full projected range of contracting to persistent areas across Europe, to assess the dendroecological indicators over recent decades in relation to species distribution model predictions. We reveal that oaks in areas projected to experience range contraction exhibited greater sensitivity to current growing season climatic conditions, whereas those in persistence areas responded more strongly to previous season conditions. Growth synchrony among trees was higher in the contraction areas, but showed no significant increasing trend over the last 70 years, as expected from ecotone theory. Temporal shifts in climate sensitivity were stronger for temperature and vapor pressure deficit in the persistence areas, whereas the climatic water balance gained importance in the contraction zones. These findings suggest that Q. robur growth is not yet being severely affected by climate change, and that the species is currently coping well with the climate changes, even in regions with projected range contractions, thereby challenging statistically derived scenarios of range shift based on species distribution models.