Kew's 2026 Report Reveals How Little We Know About the Fungi That Sustain Life on Earth
- Marc Violo
- Jul 15
- 5 min read
The Royal Botanic Gardens, Kew has published its State of the World's Plants and Fungi 2026 report, revealing the scale of what remains undiscovered in the fungal kingdom.
Fungi underpin nutrient cycling, forest connectivity, and food systems, yet the majority of species remain formally undescribed by science.
The findings carry urgent implications for conservation, medicine, and food security at a time when fungal habitats face mounting pressure from land-use change and climate disruption.
A Kingdom Still Largely Unknown
There is a persistent gap between what fungi do for life on Earth and how much attention science pays them. The Royal Botanic Gardens, Kew's State of the World's Plants and Fungi 2026 report attempts to close that gap, at least in terms of awareness, by assembling the most current evidence on the state of the fungal kingdom. The picture it paints is one of extraordinary ecological importance combined with remarkable scientific ignorance.
Fungi are not plants. They are not animals. They occupy their own biological kingdom, one that includes everything from the yeasts used in bread and beer to the mycelium networks threading through forest soils and the pathogens capable of decimating crop harvests. Despite their ubiquity, the report makes clear that the formal scientific description of fungal diversity remains deeply incomplete.
The challenge is partly one of scale. Fungi are estimated to number in the millions of species globally, yet only a fraction have been formally described and named. The State of the World's Plants and Fungi 2026 report underscores that the rate of new species discovery remains high, which is simultaneously encouraging and sobering: encouraging because it shows science is catching up; sobering because it confirms how much remains invisible to formal taxonomy.
What Fungi Actually Do
The ecological roles fungi perform are not marginal. Mycorrhizal fungi, which form symbiotic partnerships with the roots of the majority of land plants, are central to how forests absorb carbon and how agricultural crops access phosphorus and water. Without these fungal networks, many terrestrial ecosystems would function very differently, or not function at all.
Beyond soil ecology, fungi are decomposers of first resort. They break down lignin, the tough polymer that gives wood its structure, in ways that most other organisms cannot. This decomposition function is what returns carbon and nutrients locked in dead wood back into circulation. The scale of this service, performed quietly across billions of hectares of forest, is difficult to overstate.
habitat in Indonesian
Borneo.
Fungi also underpin food systems more directly. The report draws attention to the role of fungi in fermentation, in the production of enzymes used across food manufacturing, and in the emerging field of fungi-based food ingredients that are beginning to offer alternatives to conventional animal proteins. The intersection of fungal biology and food security is not a future prospect; it is already operational.
The pharmaceutical dimension is equally substantial. Fungi have historically been the source of some of medicine's most important compounds, penicillin being the most cited example. The Kew report situates this legacy within a broader argument: that the undiscovered majority of fungal species represents a reservoir of bioactive compounds whose potential remains largely untapped. Research into fungal bioactive compounds continues to yield new candidates, as recent surveys of novel fungal chemistry have demonstrated.
The Threats Accumulating Against Fungi
The report does not confine itself to cataloguing what fungi do. It also documents what is being done to the habitats that fungi depend upon. Land-use change, driven by agricultural expansion, remains the primary pressure. When forest is converted to farmland, the complex fungal communities associated with that forest do not simply relocate; they are largely lost, along with the ecological services they provided.
Climate change compounds these pressures. Shifts in temperature and precipitation alter the conditions under which fungal species can survive and reproduce. Species with narrow ecological tolerances are particularly vulnerable. The difficulty, from a conservation standpoint, is that the baseline data needed to track fungal population trends is thin. You cannot monitor the decline of a species that has never been formally described.
Invasive fungal pathogens represent a further and more acute threat, one that cuts across ecosystems and across kingdoms. Fungal disease has driven amphibian population collapses globally, through the chytrid fungus Batrachochytrium dendrobatidis. The ash dieback pathogen Hymenoscyphus fraxineus has transformed forest landscapes across Europe. The report places these examples within a pattern of increasing pathogen pressure that is partly driven by globalised trade and movement of biological material.
Conservation Without a Complete Map
The central practical difficulty raised by the Kew report is this: effective conservation requires knowing what you are trying to conserve. For plants, decades of systematic survey have produced reasonably comprehensive species inventories for most regions. For fungi, no equivalent exists.
This gap has consequences for policy as much as for science. Protected areas are typically designed around the distribution of charismatic or well-studied species; fungi rarely feature in the criteria. Fungi are largely absent from the international conservation frameworks that govern what gets protected and how. The Kew report argues, implicitly if not always explicitly, that this needs to change.
Citizen science and environmental DNA sampling, a technique that detects species from trace genetic material in soil or water, are beginning to accelerate fungal discovery. These tools cannot fully substitute for the expertise of trained mycologists, a profession whose numbers remain modest relative to the task. The report draws attention to the geographic concentration of mycological expertise in high-income countries, while much of the world's fungal diversity is concentrated in tropical and subtropical regions where specialist capacity is thinner.
The Fungi Foundation's conservation tracking initiatives represent one attempt to build the kind of distributed, community-supported baseline data that formal science has so far been unable to generate alone.
Limitations and What Comes Next
The State of the World's Plants and Fungi 2026 is a synthesis report, not a primary research publication. Its strength lies in aggregating current knowledge across disciplines; its limitation is that the underlying data, particularly on fungal population trends and extinction risk, remains sparse. The report itself is candid about this. Many of the assessments it makes are qualified by the absence of the very evidence needed to make them with confidence.
What the report does establish clearly is a direction: more investment in fungal taxonomy, more inclusion of fungi in conservation frameworks, and a broader recognition that the services fungi provide to ecosystems, medicine, and food systems are not separable from the question of whether fungal species survive. That argument, at least, does not require more data to make.
