Previous attempts to develop straw-based bioenergy systems have stumbled at costs of transporting this low-density resource to large-scale, centralized facilities. Success in developing small-scale, distributed technologies (e.g. syngas or pyrolysis bio-oil) that reduce these costs will depend on closely matching system requirements to spatial distribution of available straw. We analyzed straw distribution in the Pacifi c Northwest to identify optimal sites for facilities ranging from a pilot plant currently under development to larger ones of previous studies. Sites for plants with capacities of 1, 10, or 100 million kg straw y -1 were identifi ed using a 'lowest-hanging-fruit' iterative siting process in which the location of maximum density of straw over an appropriately sized neighborhood was identifi ed, distance from that point necessary to include desired quantity of straw measured, straw assigned to that plant removed from the raster, and the process repeated until all available straw had been assigned. Compared to K-means, our new method sited the fi rst 44% of plants at superior locations in terms of local straw density (i.e. lower transportation costs) and the next 39% at equivalent locations. K-means produced better locations for the fi nal 17% of plants along with superior average results. For the smallest facilities at locations defi ned by 3-year average available straw density, 1.2 km buffers were adequate to provide straw for the fi rst 10% of plants, with twice that distance suffi cient for the fi rst 70%. For the largest plants, 12 km buffers satisfi ed the fi rst 10% of plants, with 24 km buffers satisfying the fi rst 60%. Buffer distances exceeded 68 km for the fi nal 20% of the largest plants. Siting patterns for the smallest plants were more evenly distributed than larger ones, suggesting that farm-scale technology may be more politically appealing. Smaller plants, however, suffered from higher year-to-year variability in straw supply within pre-defi ned distances. Published in