In an ambitious response to escalating climate challenges, Luxembourg has launched one of Europe's most comprehensive forest resilience research initiatives. On Thursday, 26 February 2026, the City of Luxembourg, in collaboration with the Ministry of the Environment, Climate and Biodiversity, the Nature and Forests Agency, and the Luxembourg Institute of Science and Technology (LIST), planted a new experimental forest as part of the FORLUX research project on the health, adaptation and sustainability of Luxembourg City forests.
The Scale of Luxembourg's Forest Crisis
Luxembourg's forests are under unprecedented stress. Luxembourg's forests, which are largely made up of beech and oak groves, are particularly vulnerable to weather events linked to climate change, with almost 60% of beech trees already showing the effects of drought, while forecasts predict an increase in the intensity, duration and frequency of these dry spells in the coming years. Recent national forest inventories paint an alarming picture: Between 2010 and 2023, forest growth volume also fell by 25% compared with 2000-2010. Calamities, dieback and bad weather conditions have contributed to this decline.
The situation has become so severe that in 2022, a government inventory shows that only 15% of the trees surveyed in Luxembourg show no damage, almost 23% are slightly damaged and around 62% are severely damaged or dead. This crisis has prompted urgent action from researchers and policymakers alike.
The FORLUX Experimental Forest: A Living Laboratory
Some 3,500 trees are to be planted on a one-hectare site in Eecherfeld, in the Muhlenbach district. What makes this project extraordinary is its scientific rigor and comprehensive approach. The site is divided into four plots, each of which is reserved for a specific combination of tree species so that researchers can study and compare different types of mixed forests: natural regeneration, broadleaf mixture, coniferous mixture, and broadleaf-coniferous mixture.
The species selection process follows strict scientific criteria. The various species were selected based on recommendations from the Nature and Forest Agency's Ecological Species Database, a decision-support tool. Only species with a high degree of resistance to heat waves, high temperatures and frost were selected. This careful curation ensures that only the most climate-resilient candidates are tested under real-world conditions.
Advanced Monitoring Technology
The project employs cutting-edge technology to gather comprehensive data. Sensors will be installed in all of the plots to collect data on the trees' health and surrounding air quality to determine how these are affected by weather conditions, the amount of water infiltration in the soil, and the amount of carbon stored in the trees and the soil. This multi-parameter monitoring system represents a significant advancement in forest research methodology.
As such, researchers will be able to observe, in real-world conditions, how climate change affects the resilience of different types of stands and their development, and what role the trees play in safeguarding groundwater quality. The integration of hydrological and carbon cycle studies makes this the first of their kind for Luxembourg's forest ecosystems and will pave the way for new forest management strategies under global change.
Broader Context: The Shift from Coniferous to Broadleaf Species
Luxembourg's forest transformation reflects broader European trends in climate adaptation. The adaptation efforts carried out in forest stands over the past two decades are starting to show results: the share of broadleaved species has risen from 66% in 2010 to 75% in 2023, and forest structure has become more diverse, with a wider mix of species and more multi-layered stands.
This shift aligns with recent scientific findings that conversion from coniferous to broadleaved trees in currently forested areas can provide cooling for summer hot extremes (e.g., reducing the monthly mean daily maximum temperature in July over Continental Europe by 0.6 °C). The research suggests that the conversion can also mitigate the undesired warming impacts of forestation with present-day forest composition in most of Europe, e.g., reversing effects on the monthly mean daily maximum temperature in July over Continental Europe from +0.3 °C to −0.7 °C.
Luxembourg's Forest Heritage: Facts and Figures
Understanding the scale of this initiative requires context about Luxembourg's forest landscape. The Grand Duchy is covered by 92,150 hectares of forest, equivalent to around 35% of Luxembourg's surface area. Hardwoods cover 64% of this area and softwoods 36%. In terms of ownership, 52% of the plots of land are privately owned by around 14,000 family companies or private individuals: 34% are municipal forests, 13% are state-owned forests and 1% of forests belong to public institutions.
The proximity of these forests to urban areas makes their health particularly crucial for residents' quality of life. More than 85% of forests are located less than 1,500 metres from a built-up area, which makes them ideal spots for leisure activities.
The Science Behind Species Selection
The project's scientific foundation rests on decades of research into climate-resilient forestry. Since many indigenous trees (e.g. beech, spruce, etc.) are being exposed to considerable stresses as a result of successive periods of drought, it is important to determine which species will be the most resistant to the hotter, drier climates that we are likely to experience in the future.
The challenges facing traditional species are becoming increasingly apparent. Almost all landowners of private forests have been affected by climate change, which has become a major issue over the last decade. Certain trees died as a direct result of drought, while others were weakened before being attacked by pathogens such as insects or fungi. Private landowners are making a huge effort to replant affected woodland areas with species adapted to climate change.
Community Engagement and Education
FORLUX goes beyond pure research, emphasizing public involvement and education. In line with the FORLUX project's focus on raising awareness, the Eecherfeld site will become a place dedicated to learning and passing on knowledge about trees and forest management. The site could eventually be used as a venue for educational visits to explain how trees function – how they grow, how their roots develop, how they interact with the soil, the physiology of their leaves, making complex forest science accessible to the general public.
Even the planting ceremony embraced this educational mission. Children from the Bëschspillschoul took part in the planting operation, connecting the next generation directly with forest conservation efforts.
Strategic Objectives and Future Impact
FORLUX is a multi-year project financed by the Ministry of the Environment, Climate and Biodiversity through the Luxembourg Climate and Energy Fund. It was set up to assess the resilience of municipal forests to the major climate changes observed over the past five years, and to support the adaptation of forest management practices to current and future weather conditions. It will also provide a better understanding of the interaction between forest health, water resources, and carbon resilience.
The project's ambitious scope encompasses three primary objectives: quantify and predict how forests respond to climate change; develop strategies for adapting forest management practices; and heighten citizen awareness of and involve citizens in forest preservation.
Integration with Broader Luxembourg Forest Policy
The experimental forest represents just one component of Luxembourg's comprehensive forest protection strategy. In July 2024, the City of Luxembourg presented its priorities and upcoming projects in the area of environmental protection. These are geared towards enhancing the resilience of Luxembourg City's forest heritage and ecosystems, further to the findings reported by the Nature and Forest Agency that the health of trees has been deteriorating for several decades.
Additional initiatives include building a forest nursery in Eecherfeld, in the district of Muhlenbach, where young trees will be cultivated using seeds from selected trees in Luxembourg City's forests that are suited to the soil conditions in our local forests. The young plants will then be replanted in the municipality's forests.
Looking Ahead: A Model for Europe
The implications of this research extend far beyond Luxembourg's borders. With the implementation of this highly innovative research project, the City's municipal forests will be among the most studied forest environments in all of Europe. The data generated will inform forest management decisions across the continent, where similar climate pressures are reshaping traditional forestry practices.
As Europe grapples with the dual challenges of maintaining forest ecosystem services while adapting to climate change, Luxembourg's FORLUX project offers a rigorous, science-based approach to forest transformation. The experimental plots in Eecherfeld may seem modest in scale, but their potential to revolutionize how we manage forests in a changing climate makes them among the most important research sites in contemporary European forestry.
The success of this initiative could provide the blueprint for climate-resilient forest management across the region, demonstrating that small nations can lead in addressing humanity's greatest environmental challenges through innovative science, community engagement, and forward-thinking policy.