Serbian spruce (Picea omorika (Pančić) Purk.) is a rare and endangered tertiary relict and endemic species, with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Since the middle of the 19th century, its natural range declines constantly, followed by a decline in the number of mature individuals. The decline of this forest species is slow and mainly attributed to poor regeneration and low competing ability. Given the foreseen worsening of the climate in forthcoming decades, this decline can only accelerate. In recent years, dieback related to drought has been observed as response to extreme weather events suggesting that Serbian spruce will face difficulties in adapting to climate change within its natural range. However, successful use of Serbian spruce in Central and Northern Europe indicates potentially large adaptive potential of this species which, along with the high genetic variability, outweigh the limited morphological variation, self-fertilization, and limitations related to the restricted natural range in the first place, and, indicates possible directions of migration in the second place. In this paper, current conservation actions are discussed, and strategies for the species survival in a changing environment are suggested. Since migration and adaptation are the least likely responses of this species to climate change, measures such as assisted migration may be the only strategy which will enable persistence of Serbian spruce. Current conservation programs, limited to in-situ actions, need to be supplemented with ex-situ actions and strategies. In the worst case scenario, i.e. for species such as Serbian spruce which are unable to migrate and/or adapt to changing climate, the most suitable sites should be identified and colonized in order to prevent extinction in the near future.

This study was carried out to compare quality and morphology in 1+0 year containerized seedlings of Turkish red pine (Pinus brutia Ten.) originating from a seed stand and a seed orchard based on height and root-collar diameter. Averages of seedling height and root-collar diameter were 13.8 cm and 2.63 mm in orchard seedlings, while they were 14.8 cm and 4.56 mm in stand seedlings, respectively. There were significant differences (p≤0.05) between seed sources for the characters according to result of ANOVA. Stand seedlings were better quality than that of orchard seedlings according to quality classification of Turkish Standard Institute. Positive and significant (p≤0.05) relations were found between the characters in both seed sources based on results of correlation analysis. Results of the study were discussed for nursery practices, plantation forestry, and genetic-breeding of the species. 

Projections of the regional climate model for Southeast Europe generally predict an increasing of temperature and a decrease in precipitation, with some local variations. Higher frequency of extreme weather events and increased flooding can also be expected. This climate change will, among other things, result in changes in habitats and species distribution, and a decrease in biodiversity. In most cases, forest ecosystems will be unable to adapt fast enough to keep pace with changes in climate. Extreme weather events and low precipitation during the growing season will cause high mortality of seedlings after planting. New forests will face the whole range of these changes because of the long lifetime of trees. Reforestation programs must take projections of climate change into consideration. In the long term, new guidelines for site-species matching, provenance selection, and genetic diversity need to be adopted. In the short term, site preparation, planting techniques, and post planting protection need to be improved. In addition, seedling quality (morphological, physiological, and genetic) and planting time need to be specific for each site. New site preparation, planting, and post-planting protection methods are useful tools for short term success measured in seedling survival and initial growth. Seedling quality is essential for short and long term success. Different strategies, such as assisted migration and increased genetic diversity of planting material, can provide better chances for long term success measured in growth, fitness, and capability to produce the next, better adapted generation.

Involvement in forest restoration programs across North America for the past 40 years, dealing with nursery cultural practices, operational seedling quality programs and defining seedling performance on restoration sites has given me a unique perspective, which I have used to examine programs from both a research and operational perspective. Certain biological patterns and themes continually appeared across these programs and this paper discusses five of the most common themes.

Learning To Think Like a Tree – It is important for practitioners to develop an understanding of the ecophysiological performance of tree species in a nursery or forest restoration program in order to understand how seedlings grow. This understanding leads to sound biologically based cultural decisions to improve seedling performance.  

Stress and the Cyclical Nature of Stress Resistance – Seedlings are exposed to stress when environmental conditions limit their performance. Plants develop physiological resistance attributes to mitigate stress and these attributes change throughout the seasonal cycle. Practitioners have developed hardening cultural practices that enhance seedling stress resistance, thereby improving seedling quality and site restoration success.

Seedling Quality: Product versus Process – Seedling quality is an important component of successful restoration. Typically seedling quality is examined from a product perspective, thus defining functional integrity, operational grading or sometimes performance potential. An alternative approach monitors the process, with product quality the final output.

Planting Stress and Seedling Establishment – Planting stress is prevalent in forest restoration. The act of planting can result in a seedling that does not have proper connections for water movement through the soil-plant-atmosphere continuum (SPAC). Seedling water stress, reduced growth performance and potentially death can occur if this SPAC connection is not restored.  

Seedling Death: Sometimes Simple and Sometimes Complicated – Seedling death can occur in restoration programs as a result of environmental extremes or incorrect management practices. Some problems can be easy to diagnose and correct practices can be implemented to rectify the problem. Other times, issues are complicated and it can be a challenge to define the potential factors causing seedling death.  

This study compares the relation of initial height and root collar diameter of bareroot hardwoods seedlings to survival and growth in first year after planting. A total of six species used in Serbian reforestation programs were tested (four native: Fagus sylvatica, Ulmus laevis, Fraxinus excelsior, and Acer pseudoplatanus and two exotic: Robinia pseudoacacia, and Quercus rubra), at 6 sites with a wide range of environmental conditions. Initial seedling height and diameter were equally related to field performance and better in forecasting growth than survival. The relation between seedlings initial morphological attributes and survival was species specific, while for all tested species growth was positively correlated to seedling size at planting. Although large seedlings kept their advantage in size, smaller seedlings grew at a higher rate. Both initial H and D should be considered as equally important in operational programs for hardwoods seedling quality testing.

Successful reforestation depends on the quality and health of seedlings. Targeted production in forest nurseries should produce plants that will be able to survive unfavorable environmental and weather conditions in Serbia. Pathogens can reduce the vitality of seedlings and decrease survival after outplanting. The most common pathogens identified on seeds of both conifer and broadleaved seedlings are presented. The most frequently used fungicides for the control of pathogens in Serbian forest nurseries, as well as the best time of their application, are reviewed.

As a consequence of past deforestation, degraded areas in Italy have been subjected to afforestation since the beginning of the XXI century. These afforestations have been done mainly with conifers (Pinus nigra, Pinus pinaster, Pinus halepensis, Pinus pinea), and with the aim to 1) protect the soil and to 2) prevent floods. Exotic forest tree species have been used for the afforestation of selected sites of the Apennine. In the case of Douglas fir, it is possible to state that after ninety years the results are very good in terms of both ecological adaptability and high growth-rate.

Nowadays, the lack of silvicultural treatments, the ageing processes, insect and fungi outbreaks have led pine afforestations to a condition of an unsteady biological equilibrium in many sites. Moreover, this condition seems to be due to additional factors related to climate change such as wind storms and dryness. The restoration of these pine afforestations is therefore one of the main aims of the present Italian forest management policy which aims to increase their level of resilience. In particular, the priority of the researchers has been given to the most fragile stands where three possible objectives of restoration measures should be considered:

1. To rehabilitate conifer stands by introducing native broadleaves when these stands are in a very degraded condition, and when the local wood energy chain needs to be started;

2. To conserve the conifer stands in the cases where the cultural, aesthetic and recreational functions, are the prevailing obtainable ecosystem services;

3. To foster the mixed stands, with the conifers of the old cycle and native broadleaves, which could increase resilience to the extreme events.

In regards of Douglas-fir stands, new silvicultural models have been developed which aim to a) conserve these stands and to b) combine a higher growth rate with a much improved mechanical tree stability.