The Classified Role of UK Forests: Adaptation to National Security Threats

In early 2026, the UK Cabinet Office released a 14-page summary of a Joint Intelligence Organisation (JIO) national security assessment detailing the security risks posed by global ecosystem degradation and collapse. For the first time, intelligence analysts, working alongside ecologists, applied formal probabilistic modeling to environmental tipping points, evaluating threats like the collapse of the Amazon rainforest or the Boreal forest belt not merely as environmental disasters, but as catalysts for state-level security crises.

Disclaimer: This article is a foresight thinkpiece exploring plausible future scenarios. It draws upon publicly available intelligence methodologies, recent academic research on forest resilience, and the sanitised 14-page summary of the UK Cabinet Office’s National Security Assessment (“Global biodiversity loss, ecosystem collapse and national security”, released January 2026). The speculative scenarios, classified annexes, and strategic options examined here represent a reasoned exercise in silvicultural foresight rather than official policy.

As reports from The Times and civil society challenges made under Freedom of Information laws made clear, the published document was a heavily sanitised executive summary. The unabridged document is thought to have said disappearing forests and rivers drying up would drive people to Europe and lead to conflict in Asia. What is not in doubt is that behind those 14 pages lies a classified draft that evaluates Reasonable Worst-Case Scenarios (RWCS) out to 2030 and 2050. Such scenarios explore cascading environmental failures that would strain global trade, disrupt agricultural systems, and threaten geopolitical stability.

As a silvologist, my work centers on understanding how forest systems behave over long time horizons. When we read this assessment through the lens of forest science, a crucial question emerges:

If the worst-case scenarios materialise, what is the true, tactical role of trees and forests in Britain’s adaptation?

In a country where woodland cover stands at just 13%—one of the most nature-depleted baselines in Europe—we cannot afford to view trees solely through the lens of carbon targets or landscape aesthetics. Under severe climate and geopolitical stress, trees shift from passive environmental assets to essential biological infrastructure.

Researchers (including this author) warned in a horizon-scanning study published in 2024 that UK forests face a ‘catastrophic forest ecosystem collapse‘ within the next 50 years if urgent action is not taken (see Tew et al 2024 in Further Reading).

1. Deconstructing the Redactions: What Threat Intelligence Looks Like

Standard intelligence assessments use structured frameworks, such as the Professional Head of Intelligence Assessment (PHIA) probability yardstick to evaluate low-probability, high-impact events. While public summaries speak broadly of “supply chain disruption” or “resource competition,” classified intelligence drafts model specific operational vulnerabilities.

Extrapolating from these analytical methods suggests five core tactical focus areas within the unredacted draft (as mapped in the infographic above). Note these are speculative as I have had no insights into the classified document.

A. Caloric Deficits and Agricultural Soil Protection

The public report notes that the UK relies on imports for a significant portion of its food and fertiliser, leaving it vulnerable if global ecological collapse triggers trade protectionism. In a severe trade disruption scenario, the UK’s immediate challenge becomes maintaining domestic crop yields without relying on imported synthetic inputs.

• The Silvicultural Role: When synthetic fertilisers and imported animal feeds are constrained, agroforestry shifts from an innovative farming practice to a core land-preservation strategy. For example, the planting of deep-rooting broadleaved trees in alley-cropping systems protects topsoil from wind and water erosion during extreme weather events. Furthermore, integrating trees into livestock systems (e.g. silvopasture or silvo-poultry) provides vital shade, reducing livestock mortality during intense summer heatwaves.

B. Strategic Biomass & Fuel Autarky

Classified energy security modeling frequently evaluates compound or overlapping crises—such as the disruption of sub-sea power interconnectors, pipeline sabotages, or imported gas blockades during European winter crises. [Autarky refers to the concept of self-sufficiency]

• The Silvicultural Role: In a severe grid-failure scenario, domestic timber stocks cease to be mere commercial building products; they become Strategic Biomass Reserves. Under-managed broadleaf woodlands (which represent roughly half of UK broadleaf cover) would be cataloged for emergency coppicing and sustainable thinning to secure decentralized, low-tech thermal heating and fuel for communities and essential local infrastructure.

C. Urban Thermal Buffering and Public Health

Classified hazard modeling frequently examines urban resilience—such as prolonged summer heatwaves exceeding 40°C occurring alongside power grid strain or failure. In dense urban centers, the urban heat island effect can escalate ambient temperatures to dangerous levels, severely impacting public health and straining emergency services.

• The Arboricultural Role: Strategic urban canopy expansion acts as passive cooling infrastructure. Mature street trees and dense mini-forests lower localised air temperatures through shade and evapotranspiration, mitigating heat-related mortality and civil unrest during thermal stress events without requiring grid power.

D. Catchment-Scale Hydrological Resilience

As global weather patterns become more volatile, severe rainfall events threaten downstream urban centres, transport corridors, and critical industrial and coastal infrastructure.

• The Silvicultural Role: Upland woodland restoration acts as natural but carefully designed hydraulic management (“hydrological acupuncture”). Deep root systems increase water infiltration into subterranean aquifers, while canopy interception slows peak runoff during extreme storms, mitigating catastrophic flood impacts downstream.

E. Geopolitical Instability and Domestic Resource Autarky

The redacted security assessment models cascading international threats—where global ecological collapse drives resource wars, mass migration, and severe trade disruptions across international borders.

• The Silvicultural Role: At a national scale, expanding domestic woodland cover reduces UK vulnerability to geopolitical shocks. By securing localised timber, bio-energy, and agricultural microclimates, the UK builds a degree of resource autarky. Furthermore, landscape-scale restoration buffers the socioeconomic stability of rural communities, helping insulate domestic systems against global supply chain volatility.

2. The UK’s Baseline Challenge: Managing Tree Scarcity

The central challenge for UK forestry in these scenarios is our starting position. Unlike Scandinavian or Central European nations with extensive woodland cover, the UK’s 13% forest cover leaves little margin for error (the UK is the second-least wooded country in Europe).

Furthermore, a significant portion of our existing softwood supply consists of even-aged conifer plantations, primarily Sitka spruce (Picea sitchensis). While highly productive, uniform monocultures carry inherent risks when exposed to novel pests, pathogens, and changing climate conditions.

To counter these threats and build genuine ecological resilience, British forestry must transition along four core pathways (as shown on the right-hand side of the infographic):

Species & Structural Diversity: Transitioning away from vulnerable monocultures toward Continuous Cover Forestry (CCF) and integrating climate-resilient species—such as Sweet Chestnut (Castanea sativa), Walnut (Juglans regia), Douglas Fir (Pseudotsuga menziesii), and native broadleaves. Management must explicitly account for compounding risks from pests, diseases, flooding, drought, and wildfire.

3D Agroforestry & Silvopasture: Integrating trees directly into crop and livestock systems to maximize multi-functional land yield, ensuring food production and ecological buffering occupy the same footprint.

Structural Heterogeneity: Moving away from clear-felling toward selective harvesting, maintaining continuous canopy cover to protect forest microclimates and soil health.

Targeted Expansion: Utilising spatial modeling and land-use optimisation to identify high-priority locations for new planting—such as riparian corridors, contour lines, degraded agricultural margins, and field corners—maximising ecological benefits per hectare.

3. From Reactive Management to Hybrid Foresight

Anticipating these complex, interconnected risks requires moving beyond traditional, static horizon scanning. In a recent paper published in Forestry: An International Journal of Forest Research (Hemery & Petrokofsky, 2026), my co-author and I proposed a framework termed Hybrid Foresight.

Such an approach draws on artificial intelligence which is very capable of continuously scanning global scientific literature, policy shifts, and environmental data for subtle “weak signals” of emerging threats. When this is combined with the contextual judgment of expert foresters and land managers, we can better anticipate systemic risks before they manifest on the ground.

Whether responding to emerging tree pathogens or adapting to shifts in global timber markets, integrating data-driven foresight with practical silvicultural expertise will be essential for maintaining resilient landscapes.

Conclusion: Trees as Biological Infrastructure

The National Security Assessment serves as a stark reminder that human security is inextricably linked to ecological stability. If the severe scenarios outlined in intelligence threat models come to pass, Britain’s trees and woodlands will play a vital role in our long-term adaptation.

Trees are not merely passive elements of the landscape; they are active biological infrastructure. They hold topsoils in place, buffer extreme temperatures, regulate water cycles, and provide essential renewable materials. By expanding, diversifying, and thoughtfully managing our tree resource today, we build the living buffers necessary to safeguard our landscapes and communities for the future.

References & Further Reading

1. Cabinet Office / Joint Intelligence Organisation (2026). National Security Assessment: Global biodiversity loss, ecosystem collapse and national security (14-page summary). UK Government / GOV.UK. https://commonslibrary.parliament.uk/research-briefings/cbp-11087/
2. Hemery, G., & Petrokofsky, G. (2026). Hybrid foresight: integrating artificial intelligence and expert judgement to address strategic challenges in UK Forest resilience. Forestry: An International Journal of Forest Research, Vol 99, Issue 4, cpag066. https://academic.oup.com/forestry/article-abstract/99/4/cpag066/8771346
3. Tew, E.R. et al. (2024) ‘A horizon scan of issues affecting UK forest management within 50 years’, Forestry: An International Journal of Forest Research, p. cpad047. https://doi.org/10.1093/forestry/cpad047
4. Dasgupta, P. (2021). The Economics of Biodiversity: The Dasgupta Review. HM Treasury, London. https://www.gov.uk/government/publications/final-report-the-economics-of-biodiversity-the-dasgupta-review