not-yet-known not-yet-known not-yet-known unknown Lichens are a conspicuous part of many ecosystems, especially arctic-alpine heaths and drylands, but their direct role in ecosystem functioning lags behind knowledge on vascular plants and other cryptogams. Lichen holobiont systems can produce enzymes In particular, the propensity for lichens to produce enzymes to degrade organic matter is poorly understood. We quantified the production of enzymes degrading microbial and plant-litter biopolymers, and tested if these activities were altered by proximity to typical alpine dwarf shrubs. We used a gentle extraction to detect enzymes that may be mobile in the environment and thus contribute to soil enzyme pools. We found that Cladonia arbuscular produces hydrolases that can degrade a range of microbial and plant litter biopolymers, but crucially that the production of plane-litter enzymes can be augmented by the presence of dwarf shrubs. Together this highlights new biogeochemical pathways in lichen system, where they may play a role in complete degradation of plant litter outside of the soil, contribute enzymes and partially-degraded organic matter to soil, and that the magnitude of these effects is a function of lichen:vascular plant interactions. Further work is urgently required to seek generality in these findings, identify the biotic and abiotic constraints to lichen enzyme production, and provide parameters to improve biogeochemical models.