Meet the chansons bee (Chenosmia group including metallic green or blue Osmia) Yes, sometimes taxonomy is weird, and names are very long.
Chenosmia bees are mason bees in the Genus Osmia. There are 150 species of Osmia in North America. You’re probably most familiar with blue orchard bees (Osmia lignaria) who are very sparkly and can be blue, green or blue-green.
Chenosmia, however, kick the sparkle, shine and vibrancy up a notch from other metallic osmia. Finding one of these uber glittery bees takes a bit of luck as there are only about 40 recorded sightings of them in Oregon.
Our pictured Ms. was alongside Abbott Creek Road in the Rogue River National Forest digging into some bird’s-foot trefoil flowers (Lotus corniculatus). We know she’s a she because of the pollen gathered under her abdomen.
That’s the first fun fact about osmia bees. While many bees have pollen baskets on their hind legs, mason bees (and some other bee species) have flat abdomens with brush-like hairs to hold pollen.
This pollen-gathering mechanism makes osmia pollinating superstars because they gather pollen much quicker than their pollen basket cousins.
How fast are they? Osmia are so fast packing pollen and zipping from flower to flower that 275 osmia can pollinate at a rate equivalent to 90,000 European honeybees. That’s “so fast it’ll make your head spin!” fast.
Moreover, osmia are native bees (the ones we really need to save) versus the introduced European honeybee (it’s right there in the name).
Osmia may not give us honey, but several species specialize in pollinating apples, almonds, plums, cherries, strawberries, blackberries and raspberries. Some eastern species specialize in pollinating blueberries, and I don’t want to imagine a world without blueberry muffins and blueberry pancakes.
If you want to woo osmia to your yard (which of course you do), provide them with a pollen buffet of native plants which bloom during peak osmia season (March – May). Plant options include Oregon crabapple, flowering currant, elderberry, huckleberry, Oregon grape, lupine, antelope bitterbrush and big leaf maple.
But wait, there’s more! To keep osmia in your yard, you’ll need to provide someplace for them to nest. While you can buy or build a “bee hotel” with wooden tubes for nestmaking, know that those do require maintenance and cleaning to prevent parasites, fungi and diseases from spreading among the bees.
If you want to make or purchase a “bee hotel,” keep these tips in mind:
A flimsy bee house may become easily damaged, and will not protect the nest cells, eggs and larvae inside.
- Made of wood
Ensure untreated wood is used. Do not use glass or plastic as these materials may help to encourage the growth of bacteria and fungi.
Pollen mites can be a problem for mason bees and can infest nests. Ensure you provide replaceable cardboard inserts for the bee house, and carefully follow the instructions.
If you feel you could not make a commitment to replace tubes, it may be better to simply leave natural hollow plant stems or a small woodpile that’s just for them. Split or whole rounds will work. Let other critters take up residence too as the bees will use holes made by other insects once those insects have abandoned them.
You can pre-drill holes in your wood pile wood as well. Holes need to be about one-quarter of an inch in diameter, and just over one-half inch in depth.
Then sit back and enjoy as your garden is pollinated by little, living sparkly ornaments.