Osmia Lignaria are native to the contiguous United States and into Canada.  They usually can be found near wooded or brushy areas in the early spring.  There are two subspecies of Osmia Lignaria in the United States, Osmia lignaria lignaria and Osmia lignaria prorinqua.  Osmia lignaria lignaria live in the more humid areas (above 60% annual humidity) while Osmia lignaria prorinqua live west of about the 100th parallel in the arid portions of the USA.  (SEE MAP)
  Their common name is the Blue Orchard Bee due to the blue cast on their blackish colored bodies.  Because of the humidity requirements of the two subspecies they cannot be moved far outside of their natural ranges.  If they are, they disperse from where they emerged to try and find the right nesting habitat and they won't re-nest in your nests.  So if you find another bee supplier - be sure they have your type of bees!  If you are near the bordering humidity lines, be sure to get at least 250 bees to get started - so they will have enough of the same subspecies to maintain a population.

Blue Orchard Bees are larger than Hornedfaced bees and will nest in a hole diameter as small as 5/16th of an inch without changing the sex ratio of the offspring.  This is the same size as the largest sized hole that Hornedfaced bees will use without changing the sex ratio.  Smaller holes may be nested in, but there will be more males produced in them.  Females are an average of twice as large as the males.  However, two males are normally produced for every female.  During tests in Utah, an average of 1 in 4 nests had bees begin nesting in them the first year - that is why I suggest getting an initial starting population.