The particular significance of the whitebark pine (Pinus heldreichii Christ.) stems from the fact that it is a tertiary relict and Balkanic subendemite covering a very narrow and intermittent area in Serbia. A representative pool of 48 adult trees originating from three populations, one recently discovered natural (Population I) and two planted populations (Populations II and III) was investigated in order to evaluate the intra- and interpopulation variability of the essential oil of the complete fund of P. heldreichii in Serbia. In the pine-needle-terpene profile, 104 compounds were detected, 84 of which could be identified. Among the essential-oil constituents, monoterpenes and sesquiterpenes dominated, comprising ca. 90% of the essential oil. The terpenic profile of Population I was characterized by a predominance of monoterpenes (e.g., limonene (1), α-pinene, and Δ(3) -carene (4)), while sesquiterpenes (e.g., germacrene D (2) and β-caryophyllene (3)) obviously preponderated in the profile of Populations II and III. This study also demonstrated that the abundance of whitebark pines in Serbia had significantly changed over the last few decades. The number of individuals in the natural population had increased, while the number of individuals in the planted populations had decreased. Today, the whitebark pine fund in Serbia comprises less than 250 trees.

Summary During the monitoring of the health status of nurseries and plantations in Serbia, a decline in a 5‐year‐old Paulownia tomentosa plantation was recorded. Trees displayed symptoms of dieback, massive breaking at different positions, the appearance of decay and fungal fruitbodies at the stems. Using standard isolation methods, white colonies with cottony surfaces and regular growth were obtained from the decaying wood samples, and after the oxidation degree analysis, it was determined that these isolates belonged to Davidson's group 6, indicating white rot basidiomycetes. To identify the isolated fungus, the ITS region of one selected isolate was sequenced. Based on the morphological analysis of the obtained colonies, collected fruitbodies and ITS sequence analysis, this fungus was identified as Trametes hirsuta. This is the first report of T. hirsuta on Paulownia tomentosa in Serbia. Irregularly performed pruning as the possible infection route and the implications of these findings are discussed.

Comparison of twelve conifer species (Abies alba, A. concolor, A. nordmanniana, A. pinsapo, Cedrus atlantica, C. deodara, Picea abies, P. omorika, P. pungens, Pseudotsuga menziesii, Taxus baccata, and Pinus nigra) in the sense of needle morpho-anatomy and pollen morpho-physiology, in correlation to air pollution, was performed for the first time. Analyzed properties of species were also compared with literature sources. Listed conifers were investigated in five Belgrade parks, characterised by different degrees of air pollution, especially CO2. Their rank, I-V, was performed from non-polluted to heavily-polluted parks. Ranking in the sense of needle morpho-anatomy and pollen morpho-physiology did not match expected ones, but park V remained the worst for many analyzed species. Trees with shorter needles had greater stomatal density, which was particularly prominent in A. alba, A. nordmanniana, P. abies, P. omorika, P. nigra and T. baccata. The pollen grains of C. atlantica and T. baccata were the most sensitive to air pollution. In some analyzed species distance of particular trees close to the heavy traffic also was in correlation with needle dimensions (P.

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Forests in Europe are, at present not endangered by soil erosion, however, this can change with climate change or intensified forest management practices. Using a newly established network of plots in beech forests across Europe, the aims of this study were 1) discrimination of soil properties and erodibility indices in relation to bedrock, 2) determination of geochemical properties and Corg influencing erodibility, and 3) assessment of the effect of soil depth on erodibility indices. Seventy-six soil samples from 20 beech forests were collected in 11 countries to quantify soil properties influencing erodibility indices clay ratio, modified clay ratio, sodium adsorption ratio, and oxides ratio. Results indicate that dominant soil properties, determined by bedrock, that correlate with forest soil erodibility indices are: Corg, pH, EC, Ca and Na ion concentrations, total-water soluble cations, and the % of sand. According to the tested indices, soil susceptibility to erosion follows the sequence: granite>andesite>sandstone>quartzite>limestone. Deeper soil horizons on granite are more susceptible to erosion than surface horizons, while this is not the case for soils on limestones. In conclusion, forest management should consider the predisposition of different soil types to erosion.