PAP 77: More beautiful forest - the contribution of onf landscape architects to the post-oil forest

Valérie Mora, Laurence Le-Legard-Moreau, Laurian Gascon, Gilles Tallier, juillet 2024

Le Collectif Paysages de l’Après-Pétrole (PAP)

À télécharger : article-77_onf.pdf (12 Mio)

The decadence of a society begins when man asks himself ‘What will happen? instead of asking himself ’What can I do? Denis de Rougemont

Forest management, a public affair for nearly seven centuries Forest resources, essential to the economic and social life of the pre-oil era, have been protected by the royal authorities since the end of the 13th century. Providing wood for craftsmen and builders, fruit, roots and acorns for livestock, woodland ownership was also a guarantee of political and military power. Nobles enjoyed the prestige and benefits of hunting rights. To ensure the control, surveillance and exploitation of the kingdom’s forests, lakes and rivers, a water and forestry authority was set up in 1346 and reformed several times during the Ancien Régime. A set of regulations for the conservation and protection of forests, the ‘forestry regime’ was defined by the Forestry Code in 1827 to ensure that forest resources were managed in the public interest. The ONF, a public industrial and commercial establishment (EPIC) created in 1966, today manages almost eleven million hectares of public forests belonging to the State and local authorities, continuing this long history ¹.

The ONF’s management of public forests is multifunctional, reflecting the diversity of resources and benefits that people derive from forest areas. The protection and management of landscapes is therefore one of the ONF’s missions, and it set up a landscape network in 1993 ². With 47 members, including 25 qualified landscape architects, the network now covers the whole of mainland France and its overseas territories. It provides its expertise to optimise the institution’s response to a range of constantly evolving challenges. Thinking about the future on the scale of decades and centuries is the basis of the forestry thinking of ONF landscape architects.

A landscape approach to ward off the many perils facing French forests today

Climate change is having a brutal impact on the forest ecosystem. In a forest area that is increasing as a result of the planting of a large amount of land previously used for agriculture, trees have fallen victim to harsh climatic and health conditions in recent years. Their growth is slowing down, dieback is threatening them and their mortality rate is increasing. Forest landscapes are changing. Without the media fanfare of a storm or flood, they are being brought down by parasites and diseases, as is already visible on a massive scale in the Grand-Est, Alpes-de-Haute-Provence and Isère regions. More than half of France’s forests could be altered within fifty years. As Albert Maillet, Director of Forests and Natural Hazards at the ONF, has said, French forests everywhere are undergoing the ordeal of a ‘silent storm’.

The ecological transition is counting on the forest’s carbon sink to absorb some of the CO2 emitted by our consumption, on its wood resources to build low-carbon passive buildings, and on its resource areas to withstand times of crisis. This desirable future remains hampered by a series of difficulties, perils and obstacles that the landscape approach makes it possible to analyse and often adequately resolve. The knowledge and expertise of forest landscape architects can make a creative and innovative contribution to multifunctional management in the current context. They can be mobilised in a bold way to propose solutions capable of reducing the threats currently weighing on the forest ecosystem. Two of its characteristics provide room for manoeuvre.

Today’s forest landscape is made up of six main species - oaks, beeches and chestnuts for broadleaved trees; pine (maritime and Scots), spruce and fir for coniferous trees - mixed with other species, secondary in importance but not in use value: wild cherry, hornbeam, lime, maple, ash, wild aspen, alder, etc. Broadleaved trees account for 67% of this large forest landscape. 44% are oaks, and over 30% are pedunculate and sessile oaks. This diversity is a considerable asset when it comes to developing a multifunctional mosaic forest that meets current and future constraints.

As a result of a combination of geographical, geological, climatic, historical and socio-economic factors, the forest landscape is the visible reflection of extremely diverse contexts. As a result, it varies greatly from one area to another. There are admirable regular oak forests on the plains, a treasure trove of historical forestry ³, alongside homogeneous plantations of black pine in the mid-mountains, the result of land reclamation in the mountains at the end of the 19th century. Some final cuttings at the end of the cycle ⁴ catch our eye, particularly when they take place in our familiar surroundings, the everyday landscape to which we are accustomed and which we don’t want to see changed. The diversity of these forest landscapes could be enriched in the coming period if we know how to respond inventively to the factors of evolution imposed by climate change.

Factors of change

Forest resources are currently under increasing pressure. To reduce our consumption of fossil fuels and ensure our energy autonomy, wood heating is developing, increasing demand for wood energy and derived products. Today, the products used for these purposes are by-products of a forestry industry that is mainly dedicated to producing timber. The market will therefore have to adapt to become a source of supply. The development of this type of production could then lead to a reduction in the long forestry cycles needed to produce quality high forest trees, in favour of shorter silvicultural practices. Non-quality forest biomass production could ultimately lead to the loss of mature, layered forest facies, those tall, old forests whose charm and majesty are due to the way in which man has chosen to manage the forest ecosystem.

Meanwhile, the development of renewable energy sources in forests is consuming the same amount of space previously given over to trees. By artificialising large parts of the landscape, the proliferation of renewable energy installations can have a major impact on the surface area and quality of woodland areas, interrupting their continuity or even leading to their disappearance.

Climate change is leading to changes in water regimes, fire risks and major shifts in the distribution of species in the forest. On a national scale, these changes have spread well beyond the Mediterranean arc. Proactive fire prevention management and efforts to maintain biodiversity are becoming priorities in a growing number of regions. These changes are having an impact on forest composition, textures and mosaics. Little by little, the structures and equipment needed to defend forests against fire are contributing to the identity of the area and are becoming the landscape motifs of a new era.

Public policies on sustainable mobility and environmental education in the forest will also have visible effects on the forest landscape. The transition to more sustainable modes of transport will reduce the need to clear land for new roads or tracks, thereby protecting ecosystems. Forests will be able to reinforce their status as specific destinations for sustainable tourism, offering visitors the chance to recharge their batteries in an environment rich in stimuli that introduce them to the realities of nature. The forest will be recognised as a medium for immersion education in national environmental education programmes. The forest, a place of tranquillity, will become a bubble of well-being in which to develop the ‘forest baths’ already tried and tested in the Vosges mountains ⁵.

Beyond the perilous consequences of the present period, the post-oil era calls for a rethink of the relationship between human activities and forest ecosystems. It aims to create sustainable balances between the conservation, production and use of forest resources, guaranteeing the economic value, environmental value and heritage value that make up the spirit of these complex areas. The effects of these choices in favour of ecological transition on the forest environment must be assessed and supported. This can be done through the deployment of various measures.

A tool for knowledge and dissemination: the photographic observatory of forest landscapes

Since 2020, the ONF has been developing a photographic observatory of forest landscapes (OPPF) to capture and share the complexity and landscape dynamics of the forest ecosystem. The tool takes into account the economic, ecological, landscape and social dimensions of the forest. Thirty years after the development of this tool to document changes in town and country, the photographic image can contribute to the collective memory of the forest by rediscovering the trace of landscape dynamics that environmental amnesia could have caused to be lost sight of. The most significant example of this is the mountain land restoration (RTM) campaigns at the end of the 19th century, which were accompanied by exemplary visual documentation. The photographic observatory makes it possible to describe the work carried out by foresters and to provide an objective basis for society’s understanding of it. It is important that as many people as possible learn about forest landscapes and have a good understanding of the reasons behind the actions carried out on a daily basis.

Several initiatives are currently being rolled out. In Provence-Alpes-Côte d’Azur (PACA), around fifty regional partners have come together: government departments, existing PPOs, the forest communities concerned, partners in the forestry and wood industry, the Ecole Nationale Supérieure de la Photographie d’Arles and two professional photographers. Alongside the collective writing workshops, a call has been launched for other partners to join the operation to identify sites to be monitored according to collectively defined objectives that will ‘tell the forest story’. These objectives are natural hazards, biodiversity, climate change observation, forest management, plantations including islands of future ⁶, free evolution, public reception, forest interfaces and edges, the energy transition, the men and women of the forest and the landscape itself.

Four hundred regional proposals resulted from this appeal. Some concern the renewal of mountain land restoration campaigns, while others, directly linked to climate change, aim to give concrete expression in the medium and long term to the effects of climate projections on forest stands. The OPPF in the PACA region is bringing together historical and contemporary photographic series, the latter consisting of man-height and drone shots.

Between June 2022 and June 2024, foresters, landscape architects, photographers, photography students, institutions, elected representatives and forest managers visited around a hundred sites together. The aim was not to find the most beautiful viewpoint, but rather one that, by combining different viewpoints, would lead to shared proposals on the views that should be followed to observe the evolution of the forest landscape. This fieldwork was accompanied by a framework note outlining the implementation, functions and uses of this knowledge tool in forest landscapes ⁷. Another PPO was launched in 2020 on the Fontainebleau massif. It describes 42 tourist sites and footpaths, emblematic landscapes such as moorland, grassland and rocky chaos, identified landscape issues such as tree dieback, areas of silvicultural intervention and places likely to change as a result of climate change or tourist pressure.

Going further with the Exploratoire photographique des paysages forestiers (Exploratory photographic study of forest landscapes)

A team from the Office National des Forêts has embarked on an internal ‘innovation challenge’ to consider extending the OPPF nationwide, including overseas, by extending it to other partners, the Centre National de la Propriété Forestière (CNPF), the Office Français de la Biodiversité (OFB), the Institut Géographique National (IGN) and the Ministère de la Transition Ecologique et de la Cohésion des Territoires. The project is now called ‘Exploratoire photographique des paysages forestiers’ and will provide dedicated geo-photo-graphic data. This enlarged group will attempt to integrate the Observatory of French Forests ⁸ so that the forest landscape, with its photographic series and cross-referenced analyses, becomes a source of knowledge and decision-making aid for forestry action. The collective promotes a more sensitive vision of the French forest, contributing to a better dialogue between the forest and society.

As knowledge of forest landscapes becomes more widespread, thanks to the OPPF and then the Exploratoire, it will be possible to design landscapes that meet the challenges of the post-oil era.

The ‘landscape intervention booklet’, a tool successfully tested in the Montmorency forest

The landscape gardeners and forest engineers in the ONF’s landscape network are helping the forest to adapt to climate change with another pragmatic solution, the landscape notebook that accompanies forestry operations. This approach was developed in the context of the crisis triggered by ink disease in the Montmorency state forest. Formerly made up of chestnut coppice under oak stands, this forest is now almost 70% chestnut. Since 2016, there has been massive and rapid dieback despite a switch to irregular high forest in 2012. The drastic sanitary cuts are transforming the landscape and are frowned upon by local people accustomed to continuous wooded areas. In 2021, a steering committee has been set up to define management principles that are more appropriate than clear-cutting. Foresters and landscape architects are working together on the ground to maintain a forest landscape that will lessen the trauma of mass felling due to the health crisis. A tool was then created for use by local forestry operators, the ‘landscape intervention booklet’. It describes new operating methods that can be combined depending on the situation. By taking into account the state of the forest cover, the geomorphology and the level of use and visibility, the appropriate management methods can be defined. At the edge of the forest or within a plot, for example, a type of regeneration known as ‘recruit line’ regeneration is recommended. Its purpose is to quickly establish a visual screen and maintain a biodiversity corridor. With the positive feedback it has received, this experiment, which was set up as a matter of urgency, will be replicated in the future across the whole geographical and thematic range that makes up the great diversity of French forest landscapes, thereby contributing to actions to adapt and renew the forest in the context of climate change.

For a post-oil forest

The deployment of OPPFs on a regional scale, the development of the Exploratoire photographique des paysages forestiers on a national scale and the carnets d’intervention extending the conclusive trial at Montmorency make up a coherent and promising response from the ONF in the service of a post-oil forest. This will enable us to meet the challenges of an ecological transition that will be facilitated and accelerated by the landscape approach. The aim of adapting and renewing the forest through landscape is to give it back its shape and health in the long term by strengthening the shared recognition of forest landscapes and landscape action within the forest, this ecosystem that animates us, fills us with wonder and provides us with well-being every day. Our post-oil forest is based on two levers for action: diversifying tree species and diversifying management methods. These must inspire as many experiments as possible, starting today. What will the forest of the post-oil era look like if decisions are taken now that make sense for the landscape everywhere? Planning developments that make use of the diversity of tree species and planting them according to site and viewpoint means creating landscapes that mimic the way in which living species settle in natural forests, or creating other landscapes, as in parks and gardens.

Let’s imagine that it’s 2070 and the French forest has changed a great deal. It has adapted to the climate change that is still underway. The erosion of biodiversity has slowed. Forests have found their place in regional planning since the balanced development of towns and countryside has meant that they are now linked by woodland. A public debate has been established through a calm dialogue between the world of forestry and that of the forest’s beneficiaries. When the woodlands are felled, landscape islands with progressive contours are systematically maintained, with a predominance of free forms in keeping with the interlocking scales within the areas.

The forest of 2070 has adapted to climate change and societal demands. Its identity is a mosaic. Mixed stands of coniferous and deciduous trees share the space with flexibility, following the main lines of the landscape. The so-called Mediterranean species - Atlas cedar, Aleppo pine, holm oak, Montpellier maple etc. - are all migrating northwards. Solid partnerships have been forged between agriculture and forestry to preserve the living world. To curb wildfires, fuel breaks are set up in a judicious and fluid manner, ensuring optimum protection for the forest. These developments contribute to the natural regeneration of the forest cover while preserving trees of environmental and landscape interest with their footprint on the ground. In terms of use, this is a shared forest, a model of care and sobriety. At a time of climate upheaval, we need to work together to develop our landscape responses to the call of a forest that deserves to be cared for because it also knows how to care for us.

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