Screening Native PNW wildflowers for Attractiveness to Pollinators and Natural Enemies

Many organizations have published pollinator friendly planting lists for home gardeners. However, most of these lists lack empirical evidence to support their choices. To our knowledge no such list exists In the Pacific Northwest; thus, there is a need for baseline research on the relative attractiveness of native wildflowers to floral visitors in our region. Such data would better inform targeted plantings designed to increase habitat value in urban area. During the summer of 2017, we conducted the first field season of a study screening 23 native Willamette Valley wildflowers for their attractiveness to pollinators and natural enemies. We planted these species at the North Willamette Research and Extension Center in meter square plots spaced six meters apart. We monitored floral visitation, floral bloom, and vacuum sampled insects weekly between April and October Though this research is ongoing, we have early findings on the attractiveness of these wildflower species to bees and natural enemies. Solidago canadensis and Symphyotrichum subspicatum were two of the more attractive perennial species, and Clarkia amoena and Gilia capitata were annual flowers highly attractive to a variety of pollinators. This project will run for several more seasons, and will result in recommended pollinator planting lists for home gardens and for agricultural areas