Recently, many people have become interested in the native blue orchard bee (Osmia lignaria)—also called the orchard mason bee—as a garden and orchard pollinator.

In fact there are two distinct subspecies of the blue orchard bee: Osmia lignaria propinqua in western North America, and Osmia lignaria lignaria in the east. The species is largely absent in the Great Plains region, although some intermediate specimens have been collected.

Most commercial producers of the blue orchard bee are located in the Pacific Northwest, where they rear the locally native western subspecies. Unfortunately, the bees are marketed nationwide, resulting in the frequent shipment of locally non-native bees to the eastern U.S. The potential ecological consequences of the western blue orchard bee hybridizing with its eastern subspecies are unknown. Similarly, these shipments have the potential to introduce locally non-native parasites and diseases. For the consumer, there is another significant drawback—the western bees may not develop in sync with local conditions, resulting in poor establishment and poor performance as pollinators.

Similarly, the package bumble bee industry, which caters to farmers and gardeners with live bumble bee colonies for crop pollination currently only produces a single eastern bumble bee species, Bombus impatiens, which like the blue orchard bee, is then shipped nationwide, often far beyond its native range. Many bumble bee scientists now believe that these commercially produced bumble bees are responsible for the introduction of one or more diseases which have decimated several bumble bee species.

There is an enormous need for managed agricultural pollinators in this country, but it is very important not to import bees that are not local, especially near wild areas, even if they are represented as being the same species as local bees.

-Eric Mader, The Xerces Society for Invertebrate Conservation

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