pollinate early spring flowers in the family Rosaceae, and will even forage under poor weather conditions. Some farmers currently manage populations of Osmia to facilitate efficient pollination on their farms. However, using non-native Osmia species as managed pollinators has ignited the spread of disease, introducing invasive bee species that increase competition for native bees. In some areas, native Osmia species are in decline as of 2020; practices to minimize the impact of non-native pollinators on wild species include prioritizing the use of native bee species, raising local bee populations, and enforcing parasite/disease screening. Management Solitary bees produce neither honey nor beeswax. They are immune from acarine and Varroa mites, but have their own unique parasites, pests, and diseases. The nesting habits of many Osmia species lend themselves to easy cultivation, and a number of Osmia species are commercially propagated in different parts of the world to improve pollination in fruit and nut production. Commercial pollinators include O. lignaria, O. bicornis, O. cornuta, O. cornifrons, O. ribifloris, and O. californica. They are used both as an alternative to and as an augmentation for European honey bees. Mason bees used for orchard and other agricultural applications are all readily attracted to nesting holes – reeds, paper tubes, nesting trays, or drilled blocks of wood; in their dormant season, they can be transported as intact nests (tubes, blocks, etc.) or as loose cocoons. As is characteristic of solitary bees, Osmia species are very docile and rarely sting when handled (only under distress such as when wet or squeezed); their sting is small and not painful, and their stinger is unbarbed. See also List of Osmia species References Further reading External links Osmia Identification Guide (female) Osmia Identification Guide (male) List of Species Worldwide Species Map Palaearctic Osmiine Bees Bee genera Taxa named by Georg Wolfgang Franz Panzer