1. 1.

      How many forests are in Italy?

    2. 2.

      What is the percentage of protected areas in Italy?

    3. 3.

      How many national parks are in Italy?

    4. 4.

      What is silviculture?

    5. 5.

      Why are trees and forests important?

    6. 6.

      What are the benefits of afforestation?

    7. 7.

      What is biodiversity?

    8. 8.

      Why is biodiversity important? Why is biodiversity important in cities?

    9. 9.

      How can biodiversity be improved?

    10. 10.

      What is landscape fragmentation and how can connectivity between natural areas be achieved?

    11. 11.

      Why is connectivity between natural areas important?

    1. 1.

      How will Parco Italia achieve its goals?

    2. 2.

      Who are the beneficiaries of the Parco Italia project?

    3. 3.

      Who is behind the project Parco Italia?

    4. 4.

      Who is investing in Parco Italia? What are their interests in the outcome?

    5. 5.

      To whom is Parco Italia addressed?

    6. 6.

      How is Parco Italia choosing the plants?

    7. 7.

      Where do the plants come from ?

    8. 8.

      Who will be in charge of the new forests? What will happen after the planting?

    9. 9.

      How are planted trees counted?

    10. 10.

      How long will it take to complete the Parco Italia project?

    11. 11.

      Why is Parco Italia also considering cities?

    12. 12.

      How is Parco Italia dealing with the topic of land use and agricultural land?

    13. 13.

      Are there any precedents to Parco Italia? What are the existing projects?

    14. 14.

      How can a project like Parco Italia attract tourism?

    1. 1.

      What are the criteria that Parco Italia is using to decide where to intervene?

    2. 2.

      How is Parco Italia evaluating the climatic characteristics of a site?

    3. 3.

      How is Parco Italia evaluating the soil characteristics prior to the design and planning of the intervention?

    4. 4.

      How is Parco Italia choosing the right tree for the right place?

    5. 5.

      How is Parco Italia designing and planning the spaces for trees in an urban context?

    6. 6.

      How is Parco Italia designing and planning the spaces for trees in an extra-urban context (agricultural/ hilly/ mountainous)?

    7. 7.

      What are the Parco Italia tree planting schemes?

    8. 8.

      How is Parco Italia planning to diversify the tree species in an urban context?

    9. 9.

      How is Parco Italia guaranteeing that the planted trees will be resilient to the effects of climate extremes?

    10. 10.

      What are the certificates and quality standards that Parco Italia requires from forest nurseries?

    11. 11.

      How is Parco Italia designing and planning to increase the connectivity between the specific interventions and the surrounding areas?

    12. 12.

      How is Parco Italia guaranteeing that the new forests and plants will maximize the ecosystem services and goods and minimize disservices?

    13. 13.

      What are the management and maintenance procedures that Parco Italia is planning to carry out to ensure that planted trees reach maturity?

1. How many forests are in Italy?

Italy contains around 11 million hectares of wooded areas, of which 9.1 million hectares are forests (where >10% of the soil is covered by trees), equivalent to around 35% of the national land mass. Forests represent the largest green infrastructure of the country.1

Source: 1. RaFITALIA (2019), Patrimonio Forestale RaFITALIA, Maggio 2019, Direzione generale delle foreste - Mipaaf

2. What is the percentage of protected areas in Italy?

In Italy, 21,3% of the land is protected, while only 1,98% of marine waters are protected.1

Source: 1. Biodiversity Information System for Europe, EU Commission and European Environment Agency, retrieved on biodiversity.europa.eu.

3. How many national parks are in Italy?

There are a total of 3,512 protected areas in Italy: 2,637 Natura 2000 sites—636 Special Protection Areas (Birds Directive) and 2,358 Sites of Community Importance (Habitat Directive)—and 875 sites designated under national laws. 1

Source: 1. Biodiversity Information System for Europe, EU Commission and European Environment Agency, retrieved on biodiversity.europa.eu.

4. What is silviculture?

Silviculture is the science of controlling the establishment, growth, composition, health and quality of forests and woodlands to meet the diverse needs and values of landowners and society on a sustainable basis.1

Source: 1. USDA Forest Service. 2004. FSM 2400 – timber management; chapter 2470 – silvicultural practices. Amendment no. 2400-2004-6 (August 13, 2004). Washington, DC: USDA Forest Service, National Headquarters (WO). 51p.

5. Why are trees and forests important?

Trees and forests have inherent value as living components of the planet and habitat for 80% of land-based biodiversity, but they also provide much-needed benefits to society, such as protection from natural hazards; absorption of 30% of man-made atmospheric pollution; provision of clean and renewable materials and fuels; improvement of air, water, and soil quality; and human physical and mental wellbeing. In cities, trees are especially helpful in adaptation to climate extremes such as heat waves and intense rainfall.

6. What are the benefits of afforestation?

Increasing forest area through natural or assisted regeneration and restoring disturbed and degraded forests, and deforested lands in the long term can increase the supply of environment-regulating, productive and cultural ecosystem services provided to local and global communities, as long as the new forests are compatible with soil, climate, and biodiversity and do not harm local communities, their rights, and their current land use.

7. What is biodiversity?

The term biodiversity refers to the variety of life on Earth at all levels, from genes to ecosystems, and can encompass the evolutionary, ecological, and cultural processes that sustain life. Humans and human cultural diversity are also part of biodiversity. The term “biocultural” describes the dynamic, continually evolving, and interconnected nature of people and place, and the notion that social and biological dimensions are interrelated.1
The UN Convention on Biological Diversity defines  genetic, species and ecosystem diversity.

Ecosystem diversity defines the number and abundance of habitats, populations and ecosystems within which different organisms live and evolve.

Species diversity includes species richness, measurable in terms of the number of the same species present in a given area, or species frequency, i.e. their rarity or abundance in a territory or habitat.

Genetic diversity defines the difference of genes within a given species; therefore, it corresponds to the totality of the genetic heritage to which all the organisms that populate the Earth contribute.

Source: 1. American Museum of Natural History, What is Biodiversity?. Retrieved from amnh.org
2. ISPRA, What is Biodiversity, retrived from isprambiente.gov.it

8. Why is biodiversity important? Why is biodiversity important in cities?

Extensive scientific research shows that more diverse ecosystems have higher productivity and are more resistant and resilient to climatic stresses. The presence of more species and the relationships between species ensure that ecosystem processes run more efficiently and generate more stable benefits to society, including health protection, food and feed production, water cycle regulation, and options for economic diversification.1 Protecting biodiversity in urban and peri-urban areas is equally important because the greater the diversity of tree species in the city, the greater the ecosystem services crucial to the health of humans and other animal and plant species. Species diversity ensures better air quality, better water quality and aquifer resources, better protection from phenomena such as landslides and flooding, reduction in soil erosion, and minimisation of risks in extreme climate events.2

Source: 1. UNFCCC, Why biodiversity matters. Retrieved from unfccc.int
2. ICLEI, 10 reasons to promote urban biodiversity. Retrieved from talkofthecities.iclei.org

9. How can biodiversity be improved?

According to the UN International Panel on Biodiversity and Ecosystem Services (IPBES), nature and its vital contributions to people, which together embody biodiversity and ecosystem functions and services, are deteriorating worldwide.1 Reversing biodiversity loss may only be achieved through transformative changes across economic, social, political, and technological spheres. Different strategies can be applied on different scales, from the macro to the micro. At the largest scale, conservation cannot be separated from climate change mitigation, halting the destruction and pollution of ecosystems, and promoting social equity and economic justice. In the sector of land and urban planning, local to regional-scale solutions include: strengthening the connectivity between natural and seminatural areas, maintaining or improving habitats in protected and unprotected forests and woodlands, restoring degraded seminatural terrestrial areas and riverside ecosystems, promoting native species, and avoiding or opposing the spread of invasive ones. To this aim, reforestation, afforestation, and renaturalization interventions—in association with a detailed management and maintenance plan—can be key solutions.2

Source: 1. IPBES Global Assessment 2019, Summary for Policymakers. Retrieved from zenodo.org
2. American Museum of Natural History, What is Biodiversity?. Retrieved from

10. What is landscape fragmentation and how can connectivity between natural areas be achieved?

Landscape fragmentation is the breaking up of larger areas of the natural land cover into smaller, more isolated patches. The physical disintegration of continuous habitats can have various causes, but it is most often caused by urban or transport infrastructure expansion or environmental degradation.1 In order to achieve connectivity between natural areas, it is important to protect, enlarge, manage, and restore natural areas and the semi-natural areas next to existing natural areas in anticipation of the future expansion of their borders and their ecological corridors (according to the EU Nature Directives).2

Source: 1. European Environmental Agency, Landscape Fragmentation pressure in Europe, June 2022. Retrieved on eea.europa.eu. 2. EU Commission, EEA - European Environment Agency, Biodiversity Information System for Europe, Connectivity, retrieved on biodiversity.europa.eu.

11. Why is connectivity between natural areas important?

Identifying, maintaining, and enhancing landscape connectivity—the degree to which the landscape facilitates the movement of individuals and species—is an important conservation tool that can reduce the negative effects of habitat loss and fragmentation. Connectivity has been shown to increase the movement of individuals, which contributes to dispersal, migration, and gene flow; promotes population recolonisation or establishment in unoccupied areas; and favours circulation and selection of genotypes better adapted to environmental challenges.1 This has a wide range of environmental implications, especially for animal and plant species that inhabit and move in the territory.2

Source: 1.Zeller K.A:, Lewsion R., Fletcher R.J., Tulbure M.G., Jennings M.K. (2020), Understanding the importance of dynamic landscape connectivity. Land 9: 303. doi.org 2.European Environmental Agency, Landscape Fragmentation pressure in Europe, June 2022. Retrieved on eea.europa.eu.

1. How will Parco Italia achieve its goals?

In order to create new ecological corridors and strengthen existing ones, it is of fundamental importance to be able to plan and correctly manage forests and woods with a view to risk prevention, to protect new and existing forests and their ecosystems from natural disturbances* and climate extremes. Parco Italia carefully selects the right tree species for the right place, increasing biodiversity through strict and rigorous selection. Parco Italia is identifying areas with high potential (high-diversity landscape features), as well as areas that show high fragmentation and where intervention is urgent. Altogether Parco Italia is identifying those areas that have the potential to become ecological corridors or future designated protected areas (following the Directives of the EU Biodiversity Strategy 2030). To achieve its goals, Parco Italia involves a network of stakeholders across many sectors and scales, from public actors to tree nurseries, private companies, businesses, and organisations. Parco Italia wants to overcome individual profits and interests to realise a shared vision for the future of biodiversity conservation in Italy.

*In ecology, a "disturbance" is defined as any event that causes a temporary change in environmental conditions that lead to a drastic change in the conditions of an ecosystem. Disturbances can be for example: fires, parasitic infestations, hurricanes, droughts, floods, gusts of wind, landslides, volcanic eruptions.1 Climate-driven disturbances in forests, such as fires, windstorms and pests (e.g. insects), are expected to rise drastically under global warming.2 Nevertheless, to certain extents natural disturbances are essential ecological processes, necessary at some level of intensity and periodicity for the long-term sustainability and productivity of most, if not all, ecosystems.3

Source: 1. Aldo Leopold Wilderness Research Institute, Disturbances, retrieved on leopold.wilderness.net
2. Forzieri G., Girardello M., Ceccherini G., Mauri A., Spinoni J., Beck P., Feyen L. and Cescatti A. Vulnerability of European forests to natural disturbances, EUR 29992 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-13884-6, doi:10.2760/736558, JRC118512.
3. Averill, Robert D.; Larson, Louise; Saveland, Jim; Wargo, Philip; Williams, Jerry; Bellinger, Melvin. 1994. Disturbance processes and ecosystem management. Washington, DC: U.S. Department of Agriculture, Forest Service. 19 p.

2. Who are the beneficiaries of the Parco Italia project?

The goal of Parco Italia is to improve the forest area and increase the environmental benefits of Italian territories by working on ecosystems that generate the most biodiversity, forests. All interventions are designed as part of a broader vision considering ecosystem services, climate mitigation and climate adaptation, and ecological connectivity over the entire national territory and beyond. The project’s beneficiaries are those who will receive or use, directly or indirectly, the ecosystem services generated by the afforestation interventions on the Italian territory. Everyone can benefit from Parco Italia, and contribute to making Parco Italia a feasible project, starting with the places that need the most care.

3. Who is behind the project Parco Italia?

The project was conceived by Stefano Boeri, developed with the AlberItalia Foundation, and initiated thanks to the support of Amazon. Parco Italia was first discussed at the “World Forum on Urban Forests 2019 - Milano Calling,” and it is continuously nurtured by collaborative transdisciplinary discourse between foresters, agronomists, urban planners, architects, and researchers. In particular, the partnership between Stefano Boeri Architetti and AlberItalia represents the scientific foundation of the project.

Stefano Boeri Architetti ranges from designing urban visions to architecture, with a constant focus toward the geopolitical and environmental implications of urban phenomena. The Research Department of Stefano Boeri Architetti works mainly on strategic urban planning projects, with a focus on sustainability, climate change resilience, urban forestry and nature-based solutions strategies, providing a scientific background to the various projects of the firm.

AlberItalia is a foundation whose main purpose is to tackle and mitigate the effects of anthropogenic climate change using nature-based solutions and providing civic and community services. AlberItalia is focusing on the following interventions: interventions and services aimed at safeguarding and improving environmental conditions and the rational use of natural resources, and interventions for the protection and enhancement of cultural heritage and the landscape, and scientific research of particular social interest.

4. Who is investing in Parco Italia? What are their interests in the outcome?

Amazon is funding the research and implementation project of Parco Italia for three years. Amazon has announced a €20 million allocation for nature-based solutions to improve environmental conditions in its communities across Europe, as part of its $100 million Right Now Climate Fund, ​​which aims to support nature-based projects across Europe to enhance biodiversity and conserve, restore and improve nature in communities. The Parco Italia programme will receive €2 million, which will support the strategic planning of the programme and initial tree planting. As a first objective, Parco Italia aims to plant 70.000 trees as part of a reforestation, afforestation, and rewilding program led by the Fondazione AlberiItalia, and Stefano Boeri Architetti. The project will also help cities, whether metropolitan areas, mid-sized, or small cities, become more climate-change resilient, improving their air quality and urban cooling while promoting the connectivity between natural and semi-natural areas to enhance biodiversity within them and working on future ecological connections.1

Source: 1. Amazon. Retrieved from aboutamazon.co.uk

5. To whom is Parco Italia addressed?

Parco Italia is addressed to anyone interested in the protection and well-being of natural areas in Italy and those who care about the ecosystems that depend on forests for survival. Therefore, Parco Italia addresses citizens to bring the project to completion, but it is also addressed to all the already existing organisations willing to create a network of shared effort. The project, in order to be feasible, requires the support of all those stakeholders that see forest restoration and rewilding as tangible assets, as well as tools to tackle and limit the effects of climate change, particularly  in territories at-risk. Finally, Parco Italia is addressed to all the associations, institutions, and research entities that can implement and complete the vision in the coming years.

6. How is Parco Italia choosing the plants?

The guiding criterion for selecting the trees to be planted is inspired by a very simple principle: the right tree must be planted in the right place.

The first aspect behind plant selection is the ecological compatibility of the species to the site and the availability of trees having a clear and certified origin in plant nurseries.

A second fundamental step in choosing the right plants and the right site preparation processes to facilitate the establishment and growth of trees is the careful evaluation of the climatic characteristics of the planting site.

The third step in deciding which tree and shrub species are most suitable for the location is to acquire a robust knowledge of the soil characteristics of the site. To obtain the first clues, it is very useful to observe the surrounding area to determine which types of trees are already present, which are developing well, and which are absent.

The aspects to consider for the selection of the most suitable species can be grouped into the following four categories:
  • Suitability of the trees to the site: the type of area (e.g., urban, peri-urban, extra-urban), the type of planting (e.g., tree rows, peri-urban forest), the characteristics of the soil, the type of climate and microclimate, the space available with respect to buildings, road infrastructures, and other plant formations already present on site, the ecological requirements and resistance to disturbances.
  • Expected ecosystem services, including, for example, temperature regulation, mitigation and regulation of the microclimate, aesthetics amelioration, shading, ability to fix carbon dioxide, relationship with other individuals/populations of organisms (e.g., birds, insects).
  • Potential disservices. Some species, in addition to the benefits, could generate problems for the human community, such as, for example, a high production of pollen that can cause allergies, the production of fruits incompatible with the management of the destination area, roots lifting, and breaking the cover of sidewalks or the road surface, and production of unpleasant smells.
  • Resilience to climate change. In some contexts, choose species that, for example, are more tolerant of drought than others or resistant to frost, temporary flooding, high air temperatures, parasites, or other diseases may prove of primary importance.
The characteristics detected during the analysis of the planting site will guide the selection of the species suitable for that specific area. The range of species identified will then be further reduced according to the ability of each species to provide the expected benefits until reaching the species that best meet the site’s needs.

7. Where do the plants come from ?

After choosing the plant species to be used in relation to the location and characteristics of the planting site, we proceed with verifying the availability of native plants in high quality standards public or private nurseries, possibly near the planting area. Nurseries must comply with environmental and cultivation criteria of nursery production (according to EU regulation Dir. 105/2003) and be able to provide all the certification elements required by Italian law. The network of forest nurseries that have established relationships with the AlberItalia Foundation is of great support. As part of the certification of propagation material, information on the origin of the forest seeds used for cultivation is included in order to combine the ecological needs of planting sites with the adaptive characteristics developed by local tree populations.

8. Who will be in charge of the new forests? What will happen after the planting?

Before sowing the first seed or planting the first plant, we pose ourselves and to the owners (public or private) a series of questions whose answers inform us of the degree of attention and care needed for the new forest that will grow: Who will take care of this tree or this forest? What steps will be needed to ensure it stays healthy, and what needs to be done at the end of its life cycle? How much time and resources must be put in place to take care of it responsibly “from cradle to grave”?

Each planting intervention also provides for the definition of criteria and times for maintenance and management and detailed planning of these interventions for the first few years following the creation of the new forest. Within the agreement or contract between the AlberItalia Foundation and the owner and/or manager of the new forest facility, specific clauses are inserted that define the management plan, the actual responsibility for the care of the wood that will develop, and the main criteria for care and maintenance.

9. How are planted trees counted?

The foremost indicator of planting success is the survival of planted trees, without which expected ecosystem services cannot be delivered. Tree plantations usually experience some mortality in the first years due to transplant damage, failure of root establishment, and unexpected disturbances such as drought or herbivory. We expect fewer than 5% of planted trees to die in the first three years. We will conduct field visits every six months to check tree health and survival status. Every tree will be geotagged and permanently recorded for long-term monitoring, including by citizen science approaches (mobile app). All seedlings that die within the first three years of monitoring will be replaced.

10. How long will it take to complete the Parco Italia project?

The ambition of Parco Italia lies in building a long-term vision that imagines planting a tree for each citizen of the 15 Italian metropolitan areas: 22 million trees planted by 2040. The Parco Italia research and implementation phases have a total duration of three years and started in September 2021. The implementation phase of the Parco Italia project will commence with planting 70,000 trees and shrubs on selected sites in the territory, which the AlberItalia Foundation together with Stefano Boeri Architetti will complete by September 2024. Also significant for the project is the construction of a roadmap that outlines the governance and, at the same time, lays the quality standards, the foundations and defines the tools for the success of the interventions, and the project, in the years to come.

11. Why is Parco Italia also considering cities?

Italy can be considered a constellation of small towns, villages, and urban areas. The inhabited centres spread throughout the country could become focal points or nodes of a vast green infrastructure connected to the Apennine ridge and the Alpine system that runs down the entire peninsula. Only through the active involvement of metropolitan areas along with small and medium-sized cities it will be possible to create powerful new alliances, leading to new value chains, greener cities, and collective action against the effects of global warming. Urban areas, as well as the small villages of the inner areas*, could become centres for monitoring and managing natural and forest resources as well as natural parks and hydrological networks. Such widespread "outposts" throughout the territory would allow for the monitoring and sustainable management of forests and enhancement of their capacity to mitigate the risks of natural disasters and climate change while also creating space for a circular economy based on the ecosystem services of the territory.

*Italy’s Inner Areas are rural areas characterized by their distance from the main service centers (education, health, and mobility). According to the latest census, Inner Areas make up 53% of Italian municipalities, covering 60% of the national territory, and are home to 23% of the Italian population.1
Source: 1. SNAI - Strategia Nazionale Aree Interne. Retrieved from agenziacoesione.gov.it

12. How is Parco Italia dealing with the topic of land use and agricultural land?

Parco Italia will take care of soil management both directly by adopting solutions that lead to dynamic development of the soil in order to favor the natural evolution of favourable physical, structural, chemical, and biological soil characteristics and indirectly by decreasing soil sealing potential and the degradation and depletion of soils. The theme of agricultural soils is tackled not necessarily in a transformative way (and therefore with their conversion into forest areas) as through the implementation of projects that can encourage the introduction of trees in agricultural contexts (for example, through agroforestry or formations of rows of trees and hedges) and food forests and the diversification of agro-ecosystems toward conditions of greater systemic sustainability and improvement of biodiversity. These interventions are also oriented toward the integrated valorisation of agricultural and agroforestry landscapes in urban, peri-urban, and rural environments.

13. Are there any precedents to Parco Italia? What are the existing projects?

Worldwide projects such as the World Park proposed by landscape architect Richard Weller, the environmentalist vision of The Half-Earth by biologist Edward O. Wilson, and continental-scale projects such as the Pan-European Ecological Network (PEEN) in Europe and the Great Green Wall in Africa have deeply inspired the vision of the Parco Italia project. Weller's World Park project stems from studying areas considered biodiversity hotspots, protected areas in over 230 countries, and overlapping routes that intersect UNESCO heritage sites, intertwining biodiversity conservation, slow mobility routes, and protection of natural areas. Weller's vision arises from the interpretive observation of the land reported in other studies conducted by international and prominent organizations such as the United Nations Convention on Biological Diversity (CBD) and the PEEN. The latter, in turn, was developed as a guide for a coherent vision of biodiversity conservation in Europe, resulting in the production of maps created by comparing and combining various national databases. Parco Italia fits into this global and continental context to provide a comprehensive representation of the natural capital and work on the unexplored potential for connectivity in Italy.

14. How can a project like Parco Italia attract tourism?

“Biodiversity hikes,” or natural hiking and cycling paths in Italy, both existing ones (like those of the CAI—the Italian Alpine Club) and potential ones, if organised into a network, can provide support for the protection and growth of forest ecosystems, as well as strengthen weighted growth in areas that could represent future centers of development through the creation of new jobs related to ecotourism. With the establishment of new and systematised existing “biodiversity paths”—in parallel with the expansion of buffer zones around national parks and the inclusion of natural and semi-natural areas among protected areas— tourism and slow tourism can be revitalised. In this process, the small towns and villages that are touched by these paths have the potential to become central nodes of areas with high tourist development prospective. Alongside this potential economic driving force created by the protection of new areas, small towns and villages will need to meet the challenge of providing excellent regional and local services, which would allow the maintenance and coexistence of large segments of the population, including both older and younger generations.

1. What are the criteria that Parco Italia is using to decide where to intervene?

The Parco Italia team uses a series of criteria, prioritizing the ecological connectivity of rural areas and the provision of regulating ecosystem services of urban ones. The sum of all the scores given to each ecological criterion provides an initial indication of suitable locations, which is then further developed according to feasibility dictated by social, economic, legislative or stakeholder constraints. For example, public land is prioritised over private plots, while the absence of actually available land, the existence of regulatory constraints (e.g. in protected areas) or high costs for planting and ancillary operations (e.g. soil depaving, herbicide protection, pollution remediation, acquisition of land rights). Finally, to complete the assessment described above, a bottom-up approach is used, taking into account and trying to reconcile the preferences of all local stakeholders - e.g. in terms of recreational activities, traditional uses and cultural significance of the landscape, coexistence with agricultural or other economic activities, or any other.

2. How is Parco Italia evaluating the climatic characteristics of a site?

Parco Italia conducts a careful assessment of the climatic characteristics of the planting site before tree planting. Investigating the macroclimate is in fact very useful for better selecting the tree species to be used. For example, tree species that suffer from prolonged water shortages will not be suitable for sites where there is (or will be) a recurrence of droughts. Likewise, trees that suffer from late frosts will not adapt well to low-lying sites and cities subject to atmospheric inversion, where it is easier for these conditions to occur. Parco Italia therefore conducts an accurate analysis of the temperature, precipitation, wind, and moisture at each plantation site, considering both average and extreme values in current climatologies and under future scenarios of climate change. Future climate projections until 2050 are extracted from downscaled regional climate models, such as COSMO-CLM maintained by the Euro-Mediterranean Center for Climate Change or Euro-CORDEX, considering both a moderate (RCP2.6) and an intense warming (RCP4.5), and accessed via publicly available web portals such as Climate4Impact1 or Climate Explorer2.

Source: 1. Climate4Impact. Retrieved from: https://www.climate4impact.eu/c4i-frontend/ ; 2. Climate Explorer. Retrieved from: https://climexp.knmi.nl)

3. How is Parco Italia evaluating the soil characteristics prior to the design and planning of the intervention?

When planting a tree and even more so during a reforestation process, the soil is a crucial element in ensuring sufficient water and nutrient availability, proper aeration of the root system and good penetration capacity. It is therefore very important to carry out an analytical description of the soil before any project choice. In Parco Italia comprehensive soil descriptions and analyses have only been carried out in the knowledge or assumption of soil criticalities and dysfunctions. To this end, the use of the Guidelines for Soil description (FAO 2006)1 was recommended to planners. For a self-assessment of soil characteristics, it was instead recommended that planners follow the "Soil Self-Assessment Manual" (Celano 2018; LIFE CarbOnFarm)2. Regardless of the type of soil analysis required, the pre-planting phase of the Parco Italia project requires, always and in any case, an expeditious assessment of the soils to estimate the clay, silty and sandy percentage and proceed with suitable practices. For example, when the soil has a strong clay component, in addition to opening an appropriately sized hole, the sides of the hole (but not the base) can be incised (or scarified) to facilitate exploration of the surrounding soil by the young roots

1. FAO, 2006. Guidelines for soil description. FAO, Rome. Retrieved on the web: https://www.fao.org/3/a0541e/a0541e.pdf 2. LIFE, CarbOnFarm project. Retrieved on web: https://www.mase.gov.it/sites/default/files/archivio/allegati/life/LifeCarbOnFarm_Manuale_autovalutazione_suolo.pdf

4. How is Parco Italia choosing the right tree for the right place?

The main aspects to consider in the selection of plant species are:
  • Adaptability to current and future climates, both average and extreme.
  • Growth rate, particularly important for CO2 capture. Resistance to water stress, plant pathogens, and parasites.
  • Resistance to pollution and soil compaction, especially in urban areas.
  • Root architecture (important for interventions near roads).
  • Size and architecture of the canopy and leaves.
  • Leaf persistence (deciduous vs. evergreen), also important for air pollution mitigation, runoff, and noise reduction.
  • Flowering and fruiting characteristics, important for increasing biodiversity, as well as for safety and recreational uses.
  • Quality of wooden and non-wooden forest products in the case of productive plantations. Wood fiber strength and susceptibility to breakage (both branches and entire plants) or uprooting. Toxicity.
  • Intensity of maintenance required (e.g., species with specific water or pruning needs), which impacts management costs.
  • Longevity, especially in urban areas where stress factors can increase individual mortality rates.
  • Aesthetic value.

5. How is Parco Italia designing and planning the spaces for trees in an urban context?

Planning and design processes must transform a “space” into a “place”- the design of new urban forests in the Parco Italia project adopts this guiding criterion. Parco Italia conceives the design of reforestation and new urban forests as the art of creating sustainable living places that are good for people and nature. A well-designed urban forest, green space, or ecological connection enhances the community's sense of well-being and responds to its needs and demands, improving sustainability and environmental quality. The effective planning and design of dedicated reforestation spaces in Parco Italia involves creating synergies between the social, biological and physical aspects of urban forests. Green spaces will attract local people more effectively when they are integrated into the urban landscape. Each green space, therefore, should be an integral part of a city's green infrastructure, providing, in combination, a range of environments and experiences for the community and a complementary environment for its built elements. The design of quiet, safe, clean, and green urban spaces can greatly improve the quality of life in cities.

1. FAO, Guidelines on urban and peri-urban forestry, 2016. By F. Salbitano, S. Borelli, M. Conigliaro and Y. Chen. FAO Forestry Paper No.178. Rome, Food and Agriculture Organization of the United Nations.

6. How is Parco Italia designing and planning the spaces for trees in an extra-urban context (agricultural/ hilly/ mountainous)?

Some general suggestions are listed below:
  • Consider climate, soil type, exposure, hydrology, and other environmental factors; these will be critical in selecting suitable tree species for the site.
  • Choose species based on site conditions and project objectives (wood production, biodiversity, hydrological protection, climate crisis adaptation, recreational purposes...), growth rate, water requirements.
  • Determine the planting density based on the project objectives (wood production, biodiversity, protection, climate crisis adaptation) and the characteristics of the selected species, considering their footprint at full growth and making sure to provide sufficient space for root expansion and tree canopy.
  • Consider the other components of the ecosystem, including the presence and abundance of animal populations (seed dispersers, herbivores, carriers of pests harmful to humans), soil and its microorganisms, and the biodiversity of the herbaceous layer.
  • Community collaboration and support can contribute to the success of the project and its long-term sustainability.

7. What are the Parco Italia tree planting schemes?

The quantitative ratio between the different trees — and thus the choice of the most suitable tree planting scheme — are evaluated by the technician based on the characteristics of the species, the environmental parameters of the site, and the functions and objectives. The planting scheme proposed by the designer is then discussed with the scientific-technical staff of the AlberItalia Foundation. Trees are arranged in geometrically regular rows or in tendentially irregular groups with various types of specific mixing taking care to leave a distance appropriate to the characteristics and the development of the crowns of the adult trees. The general numerical reference is to consider planting distances that, regularized in geometric form, involve distances of 3-4 m between trees. Shrubs can be included in the planting in various ways: individually, in rows, or in groups between trees. In general, planting schemes are highly dependent on the prevailing function to be served by the urban forest. In this sense, the final schemes adopted were inspired by the functional tree planting schemes reported in Calamini et al. (2013) 1

1. Calamini, G., Colangelo, G., Giovannini, G., Lafortezza, R., Maetzke, F., Mariotti, B., Nocentini, S., Salbitano, F., Sanesi, G., Tani, A. 2013, L’impianto, la gestione e la valorizzazione multifunzionale dei boschi periurbani. Interventi forestali non produttivi per la valorizzazione dei boschi. Supporti tecnici alla Legge Regionale Forestale della Toscana 9). Regione Toscana, Firenze. Pp. 178. Retrieved on web: https://www.regione.toscana.it/documents/10180/13328713/1_impianto,%20la+gestione+e+la+valorizzazione.pdf/c97d564e-b358-4be8-9bb5-f3d57f20b977

8. How is Parco Italia planning to diversify the tree species in an urban context?

The design of forest plantations in any Parco Italia project is oriented, among other objectives, towards increasing biodiversity. Generally speaking, as a basic strategy for the conservation and enhancement of biodiversity, we are committed to following the principles established by Santamour in the '10-20-30' rule for urban tree diversity. This means that the composition of urban forests in a city should not exceed 10% trees of the same species, 20% trees of the same genus and 30% of the same family (Santamour, 1990)1. In addition, when possible, we have also tested the '20-40-25-25 rule', which dictates that no more than 20% of the same tree species, 40% of the same genus and no more than 25% of shrubs of the same species should be planted. Our approach to promoting biodiversity involves planting in groups, where trees and shrubs are associated in schemes for future habitat formation. In addition, programmes for the future adaptive management of new urban forests consider it crucial to maintain this diversity of tree and shrub species for as long as possible.

1. Santamour F., Trees for urban planting: diversity, uniformity and common sense, (1990). In: Proceedings of the 7th Conference of the Metropolitan Tree Improvement Alliance 7: 57–65.

9. How is Parco Italia guaranteeing that the planted trees will be resilient to the effects of climate extremes?

  • Select species or provenances that are resilient to the impacts of extreme weather events, possessing characteristics such as resistance to droughts, high humidity, storms or fires.
  • The presence of different species that may have different tolerances to extreme climate events can increase resilience and reduce the risk of large-scale negative impacts
  • Heterogeneity on a landscape scale implies creating areas of different age and composition, planning connectivity corridors and dividing the area into smaller manageable units which can help reduce the spread of fires, the spread of diseases and the loss of trees during extreme events.
  • Pay special attention to soil and water conservation in forest planting. Maintaining continuous soil cover, using mulching techniques, and promoting water conservation can reduce the negative effects of extreme weather events, such as soil erosion or water scarcity.
  • Long-term, in-field and remote monitoring of forest resilience indicators, such as vitality, species diversity, regeneration capacity and response to extreme events, in order to adapt management practices.

10. What are the certificates and quality standards that Parco Italia requires from forest nurseries?

European and national legislation requires certification of forest reproductive material (FRM). National Decree 386/2003 establishes minimum morphological criteria for evaluating seedlings of listed species. The Parco Italia pilot projects use additional criteria for seedling evaluation. After species selection, the first step is to select an appropriate geographic provenance based on project objectives and nursery availability. Preference is given to RNBS-registered provenances that are classified as "selected" and meet key project success criteria such as growth, stem quality, adaptability, pest resistance, etc. In the case of multiple provenances, preference may be given to drought-adapted provenances. Alternatively, local provenances will be preferred to maintain site genetic diversity. Phytosanitary and morphological assessments are performed on nursery samples, typically including seedling age, growth, apical dominance, above and below ground biomass, ratio, and root structure. Containerized FRM is the standard choice, with morphological aspects assessed in terms of container volume, depth, width and structural features to prevent root system problems.

11. How is Parco Italia designing and planning to increase the connectivity between the specific interventions and the surrounding areas?

Parco Italia always takes into consideration the location and distance from the nearest natural areas, parks or other neighbouring natural or semi-natural areas, both in urban and peri-urban or suburban contexts. Especially in urban contexts, Parco Italia will consider factors related to the distribution of green areas in order to plan, in the long term, green networks that cover the entire city or territory, guaranteeing fair and well-distributed access to green areas, trying to avoid the concentration of interventions in one or a few sectors. At the same time Parco Italia promises to strengthen intervention after intervention, a green network that is well interconnected in order to promote the conservation of biodiversity: linking balanced and resilient mini-ecosystems to each other.1 The planner/forester or administrations can use already existing free software tools to assess connectivity and the "nodes" where it is lacking, such as JRC's Guido's Toolbox2 or the Conefor3 software, or directly access the mapping conducted by Parco Italia on the entire Italian territory, which identifies the areas with high priority.

1. Vademecum AlberItalia. Retrieved from https://www.alberitalia.it/filevari/Alberitalia.it-vademecum/alberitalia.it-vademecum.html ; 2. Joint Research Center, Guidos Toolbox. Retrieved from: https://forest.jrc.ec.europa.eu/en/activities/lpa/gtb/ ; 3. Conefor. Retrieved from: http://www.conefor.org/

12. How is Parco Italia guaranteeing that the new forests and plants will maximize the ecosystem services and goods and minimize disservices?

Parco Italia will develop six complementary strategies.
  • Participatory planning. Planning a new forest in the city, planting trees and caring for them are actions that concern the whole community.
  • Selection of species suitable to meet the needs of the local community and consistent with the overall purpose of planting. The selection of species will also take into account the disruption they may cause, so that they are not used or minimised in appropriate contexts.
  • Correct implementation of plantations. After planning, the operational implementation of each plantation is the first guarantee of success.
  • Periodic monitoring of the urban and peri-urban area's tree and shrub heritage. The activation of a monitoring programme provides an early warning of the presence of pests, diseases and threats, which can be managed at an early stage while minimising disruption.
  • Timely administration of cultivation treatments. The administration of cultivation treatments is closely linked to the monitoring of plant development conditions and the occurrence of disruptions.
  • Shared replacement of diseased plants.

13. What are the management and maintenance procedures that Parco Italia is planning to carry out to ensure that planted trees reach maturity?

Tree care in the first few years after planting includes:
  • Irrigation. One of the first causes of plantation failure is the drying up of the roots and, subsequently, of the plant. It is recommended at least for the first few years, to provide a systemic and/or emergency irrigation system, monitoring the vegetative state of the plants during drought and hot periods.
  • Weeding. The aim is to mitigate water stress during prolonged drought events, and optimizing tree growth by controlling competition for light with weeds.
  • Plant replacement. In the event of a high recurrence of tree failure due to desiccation, it is correct to replace them, if necessary, with more suitable species. Before the plant's replacement it is necessary to identify the cause of death.
  • Continuous monitoring for the presence of serious pests and diseases, establishing control and containment measures where necessary.

1. FAO, Guidelines on urban and peri-urban forestry, 2016. By F. Salbitano, S. Borelli, M. Conigliaro and Y. Chen. FAO Forestry Paper No.178. Rome, Food and Agriculture Organization of the United Nations.