The worldwide decline in bee populations is threatening the delivery of pollination services, thus leading to the development of pollinator restoration strategies. In the United States, one way to protect and restore bee populations is to use seed mixes composed of pollinator-friendly native plants to revegetate federal lands following disturbance. However, we lack information about which native plant species and mixes are best for bees. We assessed the attractiveness and use by bees of 24 native plant species that are standard for revegetation projects (focal plants) on national forest lands in western Montana. Focal plants that had the highest visitation rate, attracted the most bee species, supported specialist bee species, and bloomed for extended periods across the landscape were considered "pollinator-friendly." Our results suggest that Salix bebbiana, Arctostaphylos uva-ursi, Lupinus sericeus, Rosa woodsii, Symphoricarpos albus, Erigeron speciosus, Symphyotrichum foliaceum, and Gaillardia aristata could create a seed mix that is effective for pollinator restoration on public lands. Pollinator-friendliness score cards are provided to allow land managers to select plant species to include in restoration mixes that benefit pollinators. Identifying mixes of pollinator-friendly native plant species that are available for restoration will allow land managers to both revegetate disturbed habitats and restore bee communities on federal lands. The methods developed in this project can be used to design seed mixes for pollinator restoration on other public lands.
Glenny, Will; Runyon, Justin; Burkle, Laura. 2022. Assessing pollinator friendliness of plants and designing mixes to restore habitat for bees. Gen. Tech. Rep. RMRS-GTR-429. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 54 p. https://doi.org/10.2737/RMRS-GTR-429.