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The aerial surface of plants, known as the phyllosphere, represents the largest environmental surface area of microbial habitation on the planet, with an estimated surface of 10 8 km 2 globally. The phyllosphere of bioenergy crops, such as switchgrass ( Panicum virgatum) , are of particular interest for bioprospecting for efficient microbial biomass degraders because of the potential for microbial adaptation to exploit leaf surfaces. The purpose of our study is to curate an isolate collection of switchgrass phyllosphere bacteria for genomic interrogation and future study of phyllosphere microbial interactions. We hypothesized that different cultivation techniques yield phylogenetically unique isolates that have specialized functions (and thus genetic pathways) to support their leaf lifestyle or have benefit for their host. These functions could include tolerance to dessication, radiation, and nutrient limitations which are important stressors on leaf surfaces. We collected leaves from switchgrass at the Great Lakes Bioenergy Center's intensive field plots (Kellogg Biological Station, Hickory Corners, MI). We washed cells from leaves and then used targeted plate‐based cultivation conditions, including several different types of media, to target phyllosphere microbial growth. We then sequenced the isolates using Sanger sequencing of the 16S rRNA gene, a marker of bacterial and archaeal phylogenetic diversity. We compared switchgrass phyllosphere gene sequences to 16S rRNA sequence databases to make taxonomic identifications of our isolates. To date, our collection includes sixty switchgrass isolates including genera belonging to Sphingomonas, Pseudomonas, Pantoea, Luteibacter, Arthrobacter, and Rhizobium. Some of our isolates can degrade cellulase. This data will complement a seasonal time course of cultivation‐independent assessment of phyllosphere diversity. As a result of this research, we expect to quantify the intra‐annual variability of switchgrass phyllosphere microbial communities and to identify core switchgrass phyllosphere members. This will help set the course for predicting and managing the dynamics of crop microbiota for the hosts' benefit. Support or Funding Information Michigan State University and the Great Lakes Bioenergy Research Center for funding the research project. The Great Lakes Bioenergy Research Center for travel funds.