The goal of the Institute for Applied Ecology’s Willamette Valley Seed Increase Program is to develop a supply of ecologically appropriate, genetically diverse native plant material for restoration of prairie ecosystems in the Willamette Valley. In creating restoration germplasm we seek to maximize genetic diversity while simultaneously protecting genetic integrity of extant native populations. In the absence of genetic data to guide appropriate movement of native seeds, we are testing the use of an ecoregion approach using a variety of research techniques. We collected seeds, defined preliminary seed transfer zones, and planted seed increase fields for each of 21 historically widespread, common species. We captured spatial and temporal genetic diversity by sampling from many populations per species over a 3-y period. Seed zone boundaries for each species were drawn at the scale of the ecoregion or smaller, depending on life history characteristics and potential for adverse genetic effects of translocation. To minimize loss of diversity through domestication selection, we planted increase fields using a novel design, the Diversity Enhancement Block. Seedlots from populations with different phenology or from different areas within the ecoregion were planted in separate adjacent blocks. This design allows harvest of each block separately as seeds mature, while still permitting plants from different regions of the valley to cross-pollinate and to produce crop seeds with maximum genetic diversity. All of our production fields have been entered into the Oregon Seed Certification Service Pre-Variety Germplasm program. We are looking for partners to participate in a buyer’s cooperative.