Native Pollinators Stewardship Bees of Portland – identification guide by City of PortlandCaring for Mason Bees – presentation by Columbia Land TrustCommon Bee Pollinators of Oregon Crops – report by Oregon Department of AgricultureSupporting Backyard Wildlife – Birds, Bugs & Mason Bees – video presentation by City of GreshamTunnel Nests for Native Bees – article by Xerces Society