Deep beneath every healthy forest lies an invisible web of mycorrhizal fungi, ancient symbiotic organisms that have sustained plant life for over 460 million years. Edinburgh-based Rhizocore Technologies is harnessing these underground networks to revolutionize forest restoration worldwide. Founded in 2021, the startup developed a proprietary fungal pellet technology that dramatically improves tree survival and growth, surprising the forestry industry and securing £4.5 million in new funding to scale in the US and beyond.
What are mycorrhizal fungi and why do trees need them?
Mycorrhizal fungi form mutually beneficial relationships with plant roots, aiding nutrient exchange and tree survival. Ectomycorrhizal fungi colonize roots of species like oak, birch, pine, beech, and lime, extending root reach and delivering water, phosphorus, and nitrogen. However, these fungi are often absent from degraded or cleared land. When forests are felled and soils disturbed, fungal communities collapse. Saplings planted on such sites struggle in biologically impoverished earth, leading to high mortality rates.
RhizoPellet technology: Engineering a fungal solution
Rhizocore produces RhizoPellets, small rectangular grey pellets placed directly into planting holes with saplings. Each pellet contains living ectomycorrhizal fungi, cultivated and selected for specific soil conditions, tree species, and geography. This precision ensures optimal performance for each site. The company has built one of the world's largest living fungal libraries, cataloging strains from global ecosystems to identify the best candidates for each context.
Research supports the approach. A 2023 study in the Journal of Fungi found that mycorrhizal inoculation significantly increased survival and photosynthesis rates of native woody plants after wildfires. A 2025 study in Plant-Environment Interactions highlighted how mycorrhizal associations shift nutrient acquisition based on soil conditions, validating Rhizocore's locally adapted strategy.
Field trial results: 97% survival rate
At Forestry and Land Scotland's Damside site, trees treated with RhizoPellets achieved a 97% survival rate after 12 months, compared to 78% for untreated saplings—a 25% relative improvement. Forestry and Land Scotland confirmed the findings and plans to expand pellet use. At Trees for Life sites, downy birch saplings with RhizoPellets grew 13 times faster than controls. Sitka spruce trials on former pasture showed 23% faster growth. Rhizocore now operates across over 100 active field sites, including heather moorlands, high-altitude locations, former farmland, and cleared forests.
£4.5 million investment to expand into North America
In November 2025, Rhizocore secured £4.5 million in a funding round led by The First Thirty, with participation from Scottish Enterprise, The Grosvenor Estate, Sand River, Generation-Re, Kibo Invest, John Thomson, and Old College Capital. The investment will fuel US expansion, where over 1.4 billion trees are planted annually. The company's production capacity for 2025-26 was already sold out, signaling strong demand. The funding will increase production, invest in the fungal library, and expand field monitoring.
Dr. Parkes emphasized the ecological urgency in North America, where wildfires, drought, and reduced milling capacity make RhizoPellet's drought-resistance properties critical.
A mycological revolution for global forestry
Rhizocore's achievements demonstrate that nature's most powerful forces are often invisible. By working with forest biology evolved over millions of years, the startup has unlocked growth and survival improvements that fertilizers and selective breeding could not replicate. As governments commit to afforestation targets for net zero, the gap between trees planted and those surviving remains a chronic failure. RhizoPellets offer a scientifically grounded, field-proven solution backed by capital ready to scale across continents.
