. . . . . . . . . "Bombus sonorus" . . "Astragalus" . . "Matthew Merrick. 2017. Bombus sonorus nectar plant Astragalus. iNaturalist.org. Accessed at <https://www.inaturalist.org/observations/5436243> on 05 Apr 2018." . . . . "http://iNaturalist.org is a place where you can record what you see in nature, meet other nature lovers, and learn about the natural world." .