Field trials were conducted in 2010 and 2011 to evaluate floristic composition of  weeds and the efficacy of pre herbicides in black locust (Robinia pseudoacacia L.) nurseries. The weed population in both years was consisted mainly of annual spring and summer weeds, and some perennial weeds. The weediness in both years was relatively high. Weed density in the untreated control plots was 106.5 plants per m2 in 2010 and 87.4 plants per m2 in 2011. The most dominant weeds were Chenopodium album, Polygonum aviculare and Amaranthus retroflexus in 2010 and Polygonum aviculare, Tribolus terestris and Cynodon dactilon in 2011. By taxonomic aspect, the weed flora was distributed in 11 families. 15 weed species were dicotyledons and 2 weed species were monocotyledons. Terophytes were the dominant life form weed category in black locust nurseries. Efficacy of herbicides 28 days after treatment (DAT) ranged from 91.0% (pendimethalin) to 95.3% (linuron) in 2010, and 74.5% (linuron) to 88.0% (pendimethalin) in 2011, respectively. Efficacy of herbicides 56 DAT ranged from 93.6% (pendimethalin) to 98.3% (linuron) in 2010, and from 74.8% (linuron) to 83.1% (pendimethalin) in 2011, respectively. Prevailing weed control by herbicides was not consistent over the years. However, efficacy of herbicides in control of prevailing weeds 28 and 56 DAT ranged from 88% to 100% in 2010 and 7% to 86% in 2011, respectively. Lower herbicide efficacy in 2011 was most likely due to high precipitation occurred immediately after herbicide application and domination of perennial weeds, particularly Cynodon dactilon. 

In forestlands on steep slopes, where the shallow soil can be considered a nonrenewable resource, erosion is of special concern. The vegetation covers, at both soil and canopy level, provides essential protection to the soil against the rainfall erosivity and reduces considerably the water erosion rate. Consequently vegetation management may affect soil erosion. We focused our attention on old coppice beech forest growing on a steep slope (28-32°) and subjected to conversion to high stand. With the aim of obtaining information on surface water flow and the mineral soil loss, three runoff-erosion plots (10 m long x 3 m wide) were installed in catchments in Lombardy Alps (Intelvi Valley, Como) at three stands: a coppice 40 years old (CpS 1968) and two conversions from coppice to high forest respectively cut in 1994 (CvS 1994) and 2004 (CvS 2004). Water run-off and sediment losses were collected from June to October 2008 and from May to October 2009 together with stand characteristics, LAI, soil surface cover, canopy cover and fine-root traits. Our results showed that the conversion practices significantly affect the water runoff and soil erosion with the younger conversion CvS 2004 showing the highest erosivity. This was due to the lower values of tree density, canopy cover, soil surface cover and fine-root biomass and length. The old coppice stand (CpS 1968) together with the older conversion stand (CvS 1994) showed comparable values of soil erosion. Therefore, the major role in protecting soil from erosion played by old coppice stand is recovered by the conversion stand after a number of years since harvesting. Our study highlights that abandoned old coppice stand plays an important role in protecting soil from erosion and claims consideration in forest management of steep forestland stands.

Most of the Iberian Peninsula has a Mediterranean climate, which strongly determines the objectives, strategies and techniques of forest restoration. This communication addresses a main forest restoration challenge for Mediterranean-climate woodlands in Spain: the transformation of old monospecific pine plantations to more diverse, resistant and resilient forest systems. I also present how afforestation methods and some ideas on plant quality have evolved in the last 80 years. Productivity of Mediterranean forests is low, which discourages private owners to invest in woodland management. Therefore, woodland management strongly relies on public funds. Large-scale afforestation in the 20^th century has created huge areas of monospecific pine plantations, which have been under thinned and are very simple structurally with almost no understory. The stands are very prone to fires, diseases and drought dieback. However, old pine plantations can facilitate the establishment of late successional trees and shrubs when properly thinned. Therefore, pine plantations are an opportunity for restoring several types of oak-dominated forests at a large scale and resources should invested to preserve and gradually transform these plantations into mixed forests. Funds should be invested in thinning progressively rather than to plant new areas. In many plantations close to oak forests remnants, thinning is the only management required. However, many pine plantations are far from seed sources and enrichment plantations together with thinning are needed. Extensive enrichment plantations are expensive. Therefore, an option is to develop a network of small islets strategically placed inside pine plantations and properly managed as seed foci to foster pine plantation colonization. This option is cheaper than conventional extensive low-density enrichment plantations but research is needed to assess its effectiveness for pine plantation transformation.

Increased summer drought and wildfires as a consequence of continuing climate change are expected to lead to disturbance of Mediterranean ecosystems. Seedlings recruitment is sensitive to both stresses and, therefore, any adaptation and restoration strategy devised to protect these forests should take into account a careful study on their effects on seedling development. As a substantial fraction of net primary productivity of forested ecosystems is channelled in the belowground compartments, the knowledge of how roots behave under stressful conditions becomes of primary importance to select the right management strategy to be implemented. This work tries to enlighten the events occurring in the fine root portion of the root system in young seedlings of three co-existing oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) under controlled conditions. We have made a comparative analysis of the effect of these two stresses, alone or in combination, with the aim to evaluate the tolerance level of these seedlings and, therefore, to obtain an indication of their recruitment potential in the field. The parameters investigated were biomass and a number of morphological traits. Data obtained suggest that a decrease in diameter could be part of a tolerance strategy in all three oaks tested together with a reduction of root length. In addition, tolerance to water shortage could require a reduction of carbon allocated belowground, in particular in the very fine roots, which leads to an overall reduction of the root system dimension. Q. trojana seedlings seem to be the fastest in resuming growth after stress interruption but a good recovery was also found for the remaining two oak species. Although our study provides interesting information regarding a possible tolerance strategy taking place in the fine root compartment when seedlings of these three oak species undergo water stress and fire treatment, more information is needed before any suggestion can be made as to which species would be best suited to make these forests more resistant to global changes.

Surface mining causes major destruction of natural landscapes and ecosystems. The most fertile, surface soil layer is lost permanently, together with vegetation, wildlife, and micro flora. Post-mining areas are characterized with diverse edaphic, topographic, hydrographic conditions, which complicate land restoration. Successful establishment of forest ecosystems on such land depends mostly on selection of tree species. The chosen plants must be capable of tolerating a wide range of acidity, fertility, moisture, and have potential to ameliorate such substrates for more demanding species. But, reforestation of heavily damaged ecosystems, such as post-mining areas, demands a new approach in seedlings production. This new approach takes into account specific requirements of habitat and integrates them into “targeted production of planting material”. A good strategy for successful reforestation of post-mining areas is the input of organic matter (compost, mulch). Also, current knowledge and experiences emphasize the potential of beneficial microorganisms such as, mycorrhizal fungi (MF) and plant growth promoting rhizobacteria (PGPR). The majority of studies that deal with beneficial interactions between trees and microorganisms are focused on the mycorrhiza, while plant growth promoting rhizobacteria are less present in silviculture. In this study, the focus is on the reforestation challenges of two mining basins, Majdanpek and Kolubara and suggests beneficial microorganisms as potential solution. The study presents results of several years’ researches on plant response to the presence of mycorrhizal fungi and PGPR. The substrates used for plant growth were Majdanpek and Kolubara mine deposals. Mycorrhizal seedlings were grown in Majdanpek mine deposal, and at the end of the experiment they had 30% higher biomass in comparison to control (seedlings without mycorrhiza). Seedlings linked with fungi had a higher survival rate. Deposals from Kolubara Mining Basin were used as a substrate for seedlings inoculated with PGPR. In the first experiment, Scots pine and Norway spruce were inoculated with Azotobacter chroococcum, Bacillus megaterium, B. circulans, B. licheniformis, B. pumilus, B. amyloliquefaciens. Inoculation resulted with higher biomass production (Scots pine 43%, Norway spruce 34%). Similar results were obtained in the second experiment where Scots pine and black locust were inoculated with Bacillus licheniformis, Aeromonas hydrophila, Pseudomonas putida and Burkholderia cepacia. Both species had higher biomass (around 20%) in comparison to un-inoculated control. The results confirmed the fact that early establishment and successful growth of vegetation on devastated areas depends on the presence and activity of soil microbes. Microorganisms as a “nature’s solution” pose the potential to alleviate reforestation challenges of anthropogenic devastated landscapes. Their presence and activity is crucial for ecosystem stability. In areas with compromised balance, their introduction is justified action for achieving the goal of long term ecosystem sustainability. 

The conducted research that involved the assessment of the census size of the black poplar population on The Great War Island, its viability and health status, levels of genetic diversity and recent changes in population served as the basis for defining the measures of in situ conservation of the available gene pool. A network of in situ conservation habitats, labeled A, B and C, were formed. The area of conservation habitat A is 27.90 ha and includes 455 individual trees of black poplar. Conservation habitat B spreads over an area of 7.84 ha and includes 192 individual trees of black poplar. Conservation site C spreads over an area of 21.25 ha and includes 260 individual trees of black poplar. Potential new areas suitable for natural regeneration have been identified in the vicinity of the conservation habitats. Their total area amounts to 16.50 ha and they are surrounded by reproductively mature black poplar trees and thus, seeds can easily be transferred to these areas. The suggested measures of in situ conservation are aimed at the maintenance and conservation of existing black poplar population in the area of Great War Island.

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.