Tannins in forest soils bind organic nitrogen into long-lasting complexes, affecting nutrient cycling and ecosystem productivity. Mycorrhizal fungi, especially ectomycorrhizal and ericoid types, can degrade these complexes, releasing nitrogen for plant uptake and influencing community composition. Further, there could be a potential role of arbuscular mycorrhizal fungi in acquiring organic nitrogen from persistent organic nitrogen complexes, albeit largely via interactions with free living bacteria. Understanding how tannins and fungi cooperate or compete to control organic nitrogen availability provides new insights into forest ecology, plant invasions, and biogeochemical cycles. These interactions are crucial in tannin-rich environments like temperate and boreal forests. We propose a conceptual framework to explore the feedback loops between plant chemistry, soil microbes, and ecosystem processes. Such knowledge is vital for predicting how forest communities will respond to climate change, land use, and invasive species, informing sustainable forest management strategies.