Lichens are an impressively stress-tolerant photosynthetic symbiosis between at least two partners, the fungus and alga – mycobiont and photobiont respectively – and a host of accessory fungi, secondary photobionts, epicorticular bacteria, etc. They are often the only macroscopic organisms capable of living on bare rock in the dry, western US owing to a suite of adaptive traits unique to the lichen symbiosis. As such, they are essential for primary succession, soil formation, and a source of biodiversity in mountainous environments. Despite their importance for ecosystem functioning, few studies have attempted to link microclimate (relative humidity, temperature, vapor pressure deficit [VPD], and light), and substrate (soil, rock, bark) to variability in lichen community composition and functional diversity. As poikilohydric organisms, lichen thallus hydration status is always in equilibrium with the environment making VPD an important driver of lichen photosynthesis and metabolism. Yet, few studies have directly measured VPD at fine scale in relation to lichen communities. Further, the majority of past work on lichen functional traits has focused on either a small selection of quantitative traits such as specific thallus mass (STM) and water holding capacity (WHC) or many categorical traits such as growth form (leprose, crustose, squamulose, foliose, fruticose). Here, we assess many quantitative functional traits (thallus size, STM, WHC, growth form, layer thicknesses, hydrophobicity, symbiont proportions, photobiont trading, thallus reflectance spectrum, reproductive type, etc.) across a broad taxonomic and environmental range to better understand tradeoffs between traits and environmental drivers of functional strategies in lichens. To do this, we established 35 plots (0.25 hectares) distributed across an elevational gradient of native environments within the City of Boulder Open Space and Mountain Parks land in Colorado. At each plot, we measured microclimate, mycobiont community composition, and functional traits for each species. Preliminary results suggest wetter (low VPD) and lower light environments host a greater taxonomic and functional diversity of lichens, while more stressful environments host fewer, specialized lichen species with a characteristic set of stress tolerance adaptations. Despite these general trends, there seem to be many successful functional trait combinations exhibited by lichens. The results of this study provide an important step toward developing a unifying functional trait framework for the lichen symbiosis.