Spring Exccursions 2025 in the Netherlands
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The Pro Silva Netherlands spring excursions will take place in 2025 on 21, 22 and 23 May in the Amerongen forestry (Utrechtse Heuvelrug).
The Annual Meeting had its homebase in Hotel Taloro, Gavoi (NU)
HOTEL TALORO
Loc. Lago di Gusana, 08020 Gavoi
Tel: +39 0784 53033 – Fax: +39 0784 53740
Email: booking(at)hoteltaloro.com
Thanks to the hospitality of PRO SILVA Italia, the international association PRO SILVA organized the annual conference 2025 in Sardinia. 70 participants from 22 countries gathered in the Sardinian province of Nuoro on 7-9 June, where they discussed, among other things, the new Pro Silva 2030+ strategy near the mountain town of Gavoi. In the historic region of Barbagia on the shores of Lake Gusana, the goals and means of supporting nature-friendly forest management in the spirit of PRO SILVA were discussed. Anne Crespin introduced the creation of the Strategy and President Tomáš Vrška to the participants and participants with the main points of the document. Several monthly members including a discussion with representatives of all culminated in a vote that approved the PRO SILVA 2030 Strategy.
The implementation of the PRO SILVA 2030+ strategy is elaborated in the so-called action plan. Great emphasis will be placed on the development and promotion of exemplary forests and PRO SILVA demonstration sites. The action plan also includes an update of the PRO SILVA principles. Given the number of members and the various types of natural environments in which nature-friendly management is carried out, it is appropriate to elaborate the basic theses of PRO SILVA, for example by geographical area. A working group consisting of representatives of the member countries will deal with the preparation and formulation of the updated PRO SILVA principles. The annual European meeting also included an introduction to the next host, Hungary. Margit Dénes invited everyone to Visegrád, where the meeting will take place on 9-11 September 2026. At the same time, the host of the European meeting for 2027 was selected, which is Croatia. PRO SILVA Portugal confirmed its hosting for 2028.
After the official meeting, a block was held that presented forests and forest management in Sardinia, including current issues of forest care in this area of the Mediterranean. The hosts from PRO SILVA Italia, which was founded in 1996 and manages 6 demonstration sites in 5 different regions of the country, also presented the objectives and activities of the LIFE GoProForMED project. It establishes an ecological network of forest habitats focused on forest production and biodiversity. The thematic lectures included, among other things, information presenting excursion sites, but also a demonstration of a model solution for forest fire prevention on a landscape scale using the example of the Alpine region.
The first field trip took place in the Seneghe area, where local community forests exploit the production potential of habitats suitable for growing cork oaks and holly oaks. The local forests grow on volcanic basalt soils at an altitude of between 300 and 800 m. The climate is warm Mediterranean with an average annual temperature of 15 °C and an annual rainfall of 800 - 1000 mm. The disadvantage of this relatively high value is that most of the rainfall falls outside the growing season. Between 2016 and 2024, a forest management plan was developed in the area with the aim of best harmonizing the requirements of owners and residents for the production of firewood, cork extraction, while at the same time meeting the requirements of sustainable and nature-friendly forest management. The plan respects ownership, takes into account the forest road network, supports production functions, takes into account the tradition of grazing, and also considers tourist usability and fire prevention.
The multifunctionality of the landscape in an area where forests have been intensively used for grazing and firewood production for centuries is beneficial to maintain in accordance with traditions and taking into account new knowledge. This is achieved by dividing the forest into four categories: forests intended for cork production, forests providing firewood, forests with a predominant cultural and social function (visitor attractiveness and safety), forests with a priority ecological function (habitats, species, biodiversity). The public forests for which the plan was developed are associated with other private properties in the Isterridorzu forest association. The structure of the stands was overwhelmingly influenced by the cultivation of stumps producing wood for burning charcoal, which ended in the 1960s. Before the plan was developed, the forests were negatively affected by the spontaneity of stump management. In particular, their extensive clearing in continuous areas. Now, limiting the area of harvested stumps and protecting the soil is an important element of management. According to the new plan, stumps make up one third of the forest area, with the rest designated for the cultivation of tall holly oak forests and cork production.
Cork oak is an important part of the local multifunctional forest. Its cultivation requires more attention than the holly oak, which is prevalent in local conditions. Unlike cork oak, it also regenerates naturally here. The bark of cork oaks is harvested when the trees reach a thickness of approximately 20 cm. The extraction of a 2-3 cm layer of bark takes place in early summer. At that time, the cork layer can be easily separated from the cambial tissue, which must not be damaged by the intervention. Harvesting is repeated once every twelve years. After 8-10 repetitions of cork extraction, the vitality of the trees decreases and it is necessary to think about renewal. Trees are usually replaced gradually, because some lose their vitality earlier or are damaged during extraction or are attacked by fungal pathogens or insects.
These trees are cut down and new ones are planted in their place. Part of the care of cork forests is also the cleaning of biomass as a prevention against forest fires. Although if a fire, which is a natural part of the renewal of Mediterranean ecosystems, were to occur, cork oak would have a better chance of spontaneous renewal than holly oak. The yield from one harvest fluctuates around 2 tons of cork from one hectare and the price of the commodity is also variable. The high-quality parts of the bark are the most valuable and are used to make cork stoppers, while the remains or lower-quality pieces are used, for example, as insulation. The local research area is monitoring how the density of the growth affects the vitality of the trees and the production of cork.
The commonly used value of the calculated circular area (G) does not have a good informative value in cork stands due to the fluctuating thickness of the trees after cork harvesting. Therefore, the canopy is used. The optimal value ensuring good tree vitality and cork production is between 60-80% of the stand cover. The goal of management is the production of quality cork and biodiversity. Therefore, the different ages of the stands (3 age groups) and the presence of biotope trees are supported. Cork production is improved by the care of elite trees, which number 150-300 per hectare and at the same time constitute a maximum of one third of the total number of trees. The target thickness is set at 60 cm.
The number of biotope trees should reach 3 per hectare. Fire prevention includes maintaining the shrub layer at a maximum of 30% of the stand coverage and preferring species that are less susceptible to burning. Stumps, which traditionally meet the basic needs of the local population by combining the production of firewood from the well-vegetatively reproducing holly oak and grazing by livestock, are partially converted into high forest. The stands are divided into 4m wide lines with a spacing of 20-25m. Where the low forest remains, the size of the completely logged area is limited and some of the trees are left in their full-grown form. Holly oak stumps are logged approximately once every 25 years with a yield of around 125 m3 of wood per hectare. After logging, the areas quickly become overgrown with shrub vegetation and the stump regeneration of the oaks is excellent.
The second day we visited the 4700 ha large forest complex Montes forest located in a mountain massif near the village of Orgosolo. The forests growing in a rugged relief of steep slopes and plateaus on limestone and slate at an altitude of 700-1300 m are mostly stumps or false trunks with a significant trace of intensive grazing and charcoal production. The forest is dominated by deciduous growths, especially evergreen holly oak, on slates the deciduous hornbeam oak has a better chance, in wetter places sticky alder. Deciduous trees occupy 80% of the area, 6% of the coniferous culture created by artificial forest regeneration with Atlas cedar, black pine and maritime pine after a large fire in 1931. The rest is covered by shrub formations, where holly, red-fruited juniper, common plantain and heather are common.
The property is managed by the state forests (Forestas), which cooperate with research institutes to plan and implement measures to improve the condition of the forest, its production, soil protection, employment, biodiversity and tourist use of the area. Since 2010, there has been a ban on planting conifers, which are very attractive from a production point of view, but in the context of climate change they have no chance of surviving for long. They will be replaced by naturally growing deciduous species with the aim of maintaining production, protecting the soil, the climate and supporting biodiversity. The stands of false oak trunks are initially intended to be grown undergrowth in a 100-120-year rotation. The ideas for the restoration of these stands do not yet have clear outlines, as the previous cultivation used vegetative renewal, thanks to the excellent stump regeneration of the oak, which can live up to 800 years.
The cultivation care focuses on 150-300 elite (target) trees, which are supported by the logging of their competitors in a payback period of 7-15 years. A maximum of 25-30% of the listed circular area is harvested at a time. The target thickness within this care for the stand stock and increasing the quality of production was set at 30 cm. During harvesting, 6 key elements are taken into account: achieving optimal stock, stand structure, its development phase, stand stability, its renewal, species diversity and its protection. Interventions are monitored on the demonstration area, which is regularly measured. The stand now has 860 trees per ha with a stand stock of 265 m3 and a listed circular area of 24.5 m². The height of the false trunk is 13 m and the average listed thickness of the stand is 25 cm. The stand is dominated by holly oak, with one percent occupied by holm oak.
Within the care of monoculture stands of holly oak, great emphasis is also placed on supporting species diversity. This is achieved by an ecological network consisting of three components of different nature and size. The basis is core areas of at least 5 ha in size, where there is no interference and they are a reservoir and the main refuge for species associated with this type of stand and a full supply of decaying wood. These core areas are complemented by so-called biodiversity islands, which are smaller and contain massive trees, stand gaps, an appropriate volume of decaying wood and support the natural character and ecological complexity of the forest. The third piece of this mosaic are habitat trees, as so-called stepping stones ensuring connectivity between the cores and biodiversity islands.
At least 3 habitat or potential habitat trees per hectare are left in stands. In mature stands, 3 lying trees are left for decomposition and another 3 decaying standing trees are left, the presence of which is encouraged by girdling. The preservation of 5 thick trees per hectare contributes to the long-term structural diversity of the stand and the increase in its ecological value. Measures to increase the diversity of the stand, including the leaving of trees to live and rotting wood, are the subject of public discussion. It is necessary to explain why wood, which was always 100% used in the past, now partly remains in the forest and contributes to the protection and improvement of the productive properties of the soil and species diversity. There is also a lively discussion about the role of this biomass in the dynamics of forest fires and their prevention. Grazing, which to some extent acts against the occurrence of fires, is no longer so intense. Nevertheless, its influence, especially on forest regeneration, remains high, also because wild ungulates also live in the Montes. Mouflons in particular are able to successfully block natural forest regeneration. In addition, game is not hunted in the local forests because they are a peaceful area for game.
The landscape and forests of the Montes region are undergoing major changes. In addition to warming, social changes are also clearly visible. Just last century, thousands of sheep, goats, pigs and cows grazed in the mountains, and charcoal was burned from the stumps of holly oaks. Today, due to urbanization and various restrictions, the number of grazing livestock is only a fraction of what it used to be. The symbiosis between man, shepherd and the local ecosystems is slowly being replaced by new relationships. The development of society, the desire for higher performance, profit, discovery and sometimes also for enforcing one's own truths by force, is placing the island's landscape, its economy and its inhabitants in a different position. They are facing challenges and temptations that they have not been able to resist so far, despite the largely traditional use and care of the landscape. Let us wish them not to lose their own face and that the nature and forests of the island, as well as the local society, develop in harmony and remain in economic, social and biological balance in the long term.
Author: Jan Kozel, Pro Silva Bohemica (3rd June 2025)
Here you can download the Presentation of the Annual Meeting 2025
Here you find the detalied program from February 6th 2025
Fotos (C) 2025 - Eckart Senitza - inlcuding also fotos from forests and landscape during travelling
