In the paper was investigated the variability of the morphological and anatomical traits of one-year-old seedlings of different species from the genus Quercus (Quercus robur L., Quercus petraea Matt. Liebl. and Quercus frainetto Ten.) cultivated in a plastic container Bosnaplast 18. The acorn was sown in November 2022, while the measurements of the studied elements were performed at the end of the growing season next year. In terms of morphological characteristics, the highest mean values of both researched parameters (root collar diameter and height) were recorded in Q. robur, followed by Q. frainetto, while the lowest mean values were found in Q. petraea. As for anatomical parameters, the following were analyzed: vessels width, the proportion of bark, pith and wood, as well as the participation of early- and latewood zones. Vessels width shows the least average values in Q. petraea, while no significant differences were recorded between Q. robur and Q. frainetto. The highest presence of wood, as well as the early zone within it, was found in Q. robur. The proportion of bark is a little bit higher in Q. frainetto compared to the other two species, while the pith proportion is significantly lower in Q. robur than in the other two species. Based on the obtained results, we can conclude that Q. robur seedlings show the best performance, before all from morphological point of view.

The regeneration of oak forests in the hilly and mountainous areas is one of the most serious and complex problems forestry practitioners face in Serbia. The success of regeneration depends on the individual or combined (often synergistic) influence of numerous biotic, abiotic, and management factors. While there is significant knowledge and experience about this process in practice so far, there is still great uncertainty regarding its proper execution and control over the influencing factors. The paper critically evaluated the available literature and current experiences from practice through a questionnaire. A comprehensive literature search was conducted, taking into consideration various databases and search engines, mostly composed of peer-reviewed publications from ISI-listed journals. A total of 187 papers were included in the base. Aiming to better understand the current state and the main problems in the regeneration of hilly-mountainous oak forests in Serbia, surveys were performed among forest practitioners. Based on this, the paper synthesized the current knowledge and addressed future perspectives in hilly-mountainous oaks management. More specifically, the factors that dominantly influence the regeneration process, their modes of action, behavior in the case of modifications, as well as the possibilities of their interaction are defined. The success of regeneration is determined by canopy openness, microclimatic conditions, presence of competitive vegetation, initial number of seedlings, and seedling growth and health, as revealed in the literature. The proposed methods for more successful regeneration and restoration of oak forests, include producing high-quality seedlings, using advanced weeding methods, developing a specific strategy for restoring native oak forests, assessing genetic resources and long-term monitoring. Overall conclusion of the conducted literature analysis is that there is a great need for conducting further long-term research on improving the regeneration systems in hilly-mountainous oak forests in Serbia.

The paper presents the study on the condition and structural stability of European beech (Fagus sylvatica L.) stands after the 2014 ice storm disturbance. The research was conducted in three pure beech stands on the Rtanj mountain in eastern Serbia. The stand condition after the ice storm was analyzed using changes in taxation elements. The assessment of tree damage was done according to the ICP Forests methodology, while the structural stability of the stands and individual trees was analyzed using the slenderness coefficient. The obtained results indicate very heterogeneous responses of beech stands to the negative impact of the ice storm. Heterogeneity is not only expressed between stands but also within individual stands. The stands after the ice storm are characterized by significantly reduced values of production indicators, but also by satisfactory stability, considering that the trees from the understory suffered the most. Statistically significant differences in the stability of trees of different dimensions expressed through the slenderness coefficient were determined. Consequently, the stands have maintained an appropriate level of stability thanks to the survival and resistance of the dominant trees that are the bearers of functions in these stands (trees with dbh > 40 cm). This indicates the great potential of silvicultural treatments that can increase the stability and resistance of stands in areas with a high risk of such phenomena. In addition, repressive action in the form of salvage logging has a very important role with the aim of ensuring the continuity of stands after damage has occurred.

This study combines research on soil physical and chemical properties as affected by four Eucalyptus species in Ruhande arboretum. The soil samples for research properties were taken from 0-20 cm depth using auger and one undisturbed core from each sampling unit was taken for the analysis of soil bulk density. Soil bulk density and moisture did not differ significantly between all treatments. Sand proportions differed significantly only between E. tereticornis and E. maidenii whereas silt and clay were non-significant. The soil under Eucalyptus was sandy, with sand proportion ranging from 66.4-71%. Bulk density increased with increasing sand whereas moisture content showed a reverse trend. The soil samples for studying chemical properties were taken as described in Nsabimana et al. 2008. All chemical parameters except base saturation differed significantly between treatments. Soil pH was strongly acidic but rich in total nitrogen and organic carbon which was attributed to higher litter production, its relatively faster rate of decomposition, and greater amount of residues produced by the eucalypts. Carbon/nitrogen ratio, CEC, and BS were high under all treatments while the available phosphorus was lower which was attributed to the low pH. Future studies should test if the species similarly affect the soil or not and confirm if the species increase soil nutrients. Benchmarked study sites should be used to enable differences in the species effects on the site if any.

Zinc deficiencies are rare in pine seedlings with less than five documented cases in bareroot nurseries. One temporary deficiency occurred after soil was land-leveled (i.e., topsoil removed) and another occurred on a peat soil after more than 2,200 kg of agricultural lime was applied before sowing. Farmers also observe zinc deficiencies on (1) over-limed areas and (2) where Zn-demanding crops are grown on areas where topsoil was removed during land leveling. Since ZnSO₄ is a naturally occurring pesticide, sometimes height growth increases are due to pest control. In pathogen-rich soils, pine growth may be improved more by the fungicidal effect than by a growth benefit from added sulphur and zinc. As a result, a pseudo-deficient response is possible when growth of non-deficient seedlings increases after treatment with large amounts of ZnSO₄ or ZnCl₂. In some trials, claims of a Zn deficiency have been made without supporting evidence from foliar tests or from tests using pathogen-free soil. Although fertilization with Zn increased seedling growth at pine nurseries in New Zealand, India, Russia, and Wisconsin, only at the Sweetwater Nursery in New Zealand did foliar tests prove a Zn deficiency.

Lowland pedunculate oak forests in the alluvium of the river Sava are of a great economic and ecological importance. Their growth and development features, and their survival, as well, mostly depend on soil moisture and available water. The paper deals with the influence of groundwater level on pedunculate oak forests condition in flooded area of Donji Srem. During four-year long research, the average (reference) groundwater level was determined, and extremes, the wettest and the driest year, were determined based on climate factors such as temperature and rainfalls. Deviation of the average from the reference groundwater level in the vegetation period during some years indicates possibility of risk zones presence. These zones are defined according to geostatistical analysis – ArcGIS, Kriging model and they are very significant for forestry practice, because they can predict some drought events and warn forestry experts to react in time in order to prevent big damages. Bearing in mind that investigated area is flooded, and that groundwater level is close to the soil surface, these anaerobic site conditions are obviously more suitable for another hygrophilous species than for pedunculate oak.

In this paper the variability of morphological (needle length and needle width) and anatomical (needle thickness, resin ducts width, epidermis thickness, hypodermis height and number of the hypodermis layers) properties of black pine (Pinus nigra J.F. Arnold) needles were studied at the intra- and inter-population levels. Two mountains in Serbia, Jastrebac and Goč, were selected as experimental plots. Three Pinus nigra trees were selected from both localities (6 in total). Obtained results showed that trees on Goč had bigger dimensions of the following elements: needle length, slightly wider needle width, epidermis thickness, hypodermis height, number of hypodermis layers and needle thickness. On the other hand, resin ducts were only slightly wider by the trees from Jastrebac. The results of the analysis of variance showed that variation between studied populations, as well as variation between trees within populations was statistically significant for all needle traits except resin ducts width and hypodermis height. 

During the 20th century, managers at sandy nurseries utilized sulphur (S) to lower soil pH and mitigate the risk of iron deficiency. During that time, however, applying S as a fertilizer was a rare event. At many nurseries, S in rain and irrigation water was sufficient to avoid visual deficiency symptoms. The S status of soil and foliage was typically unknown, and many researchers did not test for S due to the additional cost. Consequently, S became the most neglected macronutrient. While a few nursery trials demonstrated that elemental S reduced damping-off and increased height growth, a majority showed no benefit after applying S at rates lower than 100 kg ha^-1.  Even so, by 1980, S-deficiencies occurred at bareroot nurseries in Alabama, Oklahoma, Virginia, Wisconsin, the United Kingdom, and likely in North Dakota and New York. The risk of a deficiency increases when N-only fertilizers are applied to seedbeds. Due to research, experience and the precautionary principle, several managers transitioned to using ammonium sulfate instead of, less expensive, N-only nitrogen fertilizers. After soil tests became affordable, managers began to ask questions about the need to apply S to seedbeds. Only a few hydroponic trials with small pine seedlings have been used to estimate “threshold” or “critical values” for foliar S.  Since an initial 1,500 μg g^-1 S value is “unreliable” for pine seedlings, some authors lowered the value to 1,100 μg g^-1 and even as low as 500 μg g^-1 S. Others ignore all estimates based on total S concentrations and, instead, monitor only foliar SO₄ levels.

As a part of networking activities of PEN-CAFoRR COST Action (CA19128), the combined meeting took place in Mitzpe Ramon, Israel from 15 to 16 March 2023. In addition to the Core Group and Working Groups Meeting, a Thematic Workshop was organized by the local organizer Dr Ilan Stavi.

Predicting future yields normally requires an estimate of site quality.  A commonly used measure is site index (SI). SI is often incorrectly quantified operationally due to the ambiguity associated with selecting “site” trees.  Plus, error in the measurement of height itself occurs.  This study quantifies the impacts on the number and timing of thinnings, and the final harvest ages, as well as financial returns when incorrectly determining SI.  Three values of SI (base age 25 years) were examined using two older generation loblolly pine plantation growth and yield simulation models from the Western Gulf, USA; 16.76 m, 21.34 m, and 25.91 m.  Firstly, a particular SI was assumed to be the “true” value, growth and yield estimates were obtained, and financial assessments were conducted.  The same process was then conducted again, but assuming that the SI was incorrectly determined by varying positively and negatively the SI by up to 1.22 m from the assumed “true” value. For these older generation plantations, incorrectly determining SI did impact the age of the first thinning by as much as 5 years.  In some cases, errors of +/- 1.22 m in SI estimation had little impact on the estimated timing of the first thinning.  Errors in SI of up to +/- 1.22 m had little impact on the number of thinnings across economic rotation ages. For both unthinned and twice-thinned stands, final harvest (clearcut) ages differed by as much as 4 years for SI errors up to +/- 1.22 m.  These errors led to differences in Land Expectation Value (LEV) up to $406.50 ha^-1.  Across the three SI (16.76, 21.34, and 25.91 m), differences in LEV ranged from $237.49 to $406.50 ha^-1.  These differences in LEV could be enough to incorrectly not conduct, or incorrectly conduct, a silvicultural operation such as an herbicide treatment or a fertilization treatment across a rotation, among other treatments.