Pollinator Paradise 
Where bees and flowers cooperate for mutual benefit

About Blue Orchard Bees, Osmia lignaria, and Hornfaced Bees, Osmia cornifrons  
Orchard bees are solitary bee species in the genus Osmia, family Megachilidae.  They are solitary because each female makes her own nest and lays her own eggs; there are no separate queen and worker castes as in honey bees.  Although they have a stinger, they are very docile, and rarely use their stinger, unlike honey bees and social wasps.  In nature they make their nests in tunnels in wood and other cavities.  We can mimic natural tunnels with artificial ones, and therefore we can manage populations of these bees.

Osmia bees are only active as adults during the spring while fruit trees are in bloom and temperatures are cool.  They are excellent pollinators, flying during cooler weather than honey bees, and later in the day.  Individual bees move more between trees than individual honey bees, and female bees always collect nectar as well as pollen, so they provide good cross-pollination for fruits such as apple that require movement of pollen between tree varieties. 

Adult Osmia bees live only for about 6 weeks, so you do not need to find resources for them for the entire season, unlike honey bees.  Inside the nest, eggs hatch into larvae and feed on pollen provisions left by the mother bee.  She creates individual cells for each bee offspring with it's own provisions.  The cells are separated by mud partitions.  After the larva finishes feeding on the provisions, it defecates and spins a cocoon.  The larvae remain in the cocoons inactive all summer.  In the fall they molt into pupae and then into adults.  They spend the winter as adults in the cocoon, and then emerge in early spring to start another generation.

Blue orchard bees, Osmia lignaria, are native to the US and Canada.  There are two different sub species, one found in the West and one in the East.  Intermediates are found in Arizona and New Mexico.  Most Osmia lignaria sold commercially come from the West.   Ours are from Portland, OR.

Hornfaced bees are native to Japan, and were introduced to the U.S. in the 1960s for pollination of fruit trees by Dr. Suzanne Batra with the USDA ARS in Beltsville, MD.   They have become established in a number of places on the east coast and the midwest.  On the west coast, I have information to suggest that they may be established in the areas around Portland, Oregon and in suburban areas south of Puget Sound in Washington.   To the best of my knowledge they are not yet established in the intermountain west or in California. 

Use of this bee for fruit pollination is controversial in the scientific community.  Many bee biologists are concerned that this species may cause a decline in populations of native fruit pollinators such as the blue orchard bee, Osmia lignaria.  In addition, when bees are introduced to areas where they are not native, their parasites can also be introduced, and the parasites may affect native species.  Recently there have been reports of a Japanese chalcid wasp that is parasitizing some populations of hornfaced bees on the east coast.   For this reason, many bee biologists believe that O. lignaria should be sold only in the same part of the country where they were collected.  They argue that local native populations of Osmia lignaria should be developed for commercial sale.

On the other hand, fruit growers who have tried both hornfaced bees and blue orchard bees often prefer hornfaced bees, which appear to be more active at the nest and in fruit trees.  To my knowledge there is no published data to prove this (if you know of some, please let me know).  My brief observation of a mixed population suggests that male hornfaced bees are more active at the nest site after emergence than are male blue orchard bees, but this does not necessarily mean that the females are more active.

Hornfaced bees are also reported to be more likely to remain in the area where they are released and nest compared with blue orchard bees.  Again, I've not seen published data to document this, but it would be useful to test.  If these bees are not likely to leave the orchard where they are released, the risk that they will impact native bee populations outside of the orchard may be low.

Because hornfaced bees are known to be established on the east coast and in the midwest, but their distribution is not confirmed in the west, I prefer to sell the O. cornifrons cocoons that I have to buyers on the east coast and midwest.    Similarly, I prefer to sell my O. lignaria to buyers in the west.

Recognizing adult hornfaced bees vs. blue orchard bees 

Hornfaced bees are brownish in color with light stripes on the abdomen.  Blue orchard bees are dark blue black.  Hornfaced bees are also a little smaller in size than blue orchard bees.  The "horn" on the face of the hornfaced bee is easy to see in the photo above, but not when observing the bees in the field.

Recognizing hornfaced bee vs. blue orchard bee cocoons

Hornfaced bee cocoons (right column in the photo) tend to be smaller, and silver in color compared to brown blue orchard bee cocoons.  Hornfaced bee cocoons have a smooth surface whereas blue orchard bees have a more crinkled surface.  Hornfaced bee cocoons often have a rim of hairs around the nipple (visible on the center right cocoon).

Generally there are more hornfaced bees per nest than blue orchard bees (average 11 vs. 7 cells in 6 inch tunnels).  Hornfaced bee cocoons are packed into the nest more tightly, with little or no space between cocoons.  Blue orchard bees are more likely to have empty space between the cocoon and the nest plug (but not always).  Male hornfaced bee cocoons are oriented on an angle, but blue orchard bee cocoons are not. 

Usually complete nests of these two species can be easily distinguished, but when a nest is incomplete, or two species have used the same nest (usurpation), some of the distinguishing characters may not be apparent and identification may be more difficult.

Hornfaced bee nests (top 3 nests) and blue orchard bee nests (bottom 3 nests) in straw liners. 
Click on image to enlarge.

Managing Osmia bees for orchard pollination

Hornfaced bees are managed in much the same way as blue orchard bees.  The books that are available about management of blue orchard bees provide general guidelines.  However, note that overwintering hornfaced bees in cocoons may not tolerate freezing temperatures as blue orchard bees do, and the timing of bee emergence with bloom may need some modifications compared with blue orchard bees.  The same nesting materials that are used for blue orchard bees work well for hornfaced bees.

Also relevant to both species of Osmia is Dr. Batra's guide to the management of hornfaced bees.

About the bee cocoons that we have for sale

The cocoons that we have for sale come from a population in the Portland, Oregon area.  Last year they were a mixed population of hornfaced bees and blue orchard bees. We separated the two species and returned only the blue orchard bees to Portland. This year we have only a very few O. cornifrons that have returned, and those will be sold to the midwest and east coast where they are already established.  Most of the O. lignaria are committed for sale, but we have a limited quantities for sale, especially to western buyers.

 We have cleaned the cocoons to remove hairy-fingered mite parasites, and we have removed any cocoons that had signs of chalcid wasp parasites.

The O. lignaria population is estimated to be about 50% female. Mortality has not yet been determined but last year 3% of the cocoons contain dead larvae or dead adults.  Sex ratio and cocoon mortality are taken into account in our pricing.  We are continuing to test our population prior to final sale, and will adjust the quantity of bees accordingly. 

Pricing 

Order ASAP!  Quantities are limited. 

Get 10% off the price of a Binderboard® if you purchase bees for the board.

Garden Package:  A minimum of 15 female and 15 male cocoons, enough for our 14-hole sampler Osmia Binderboard®.
Shipped in a small emergence box. (Binderboard® sold separately)
Osmia cornifrons  $25. 00  Sold out
Osmia lignaria        $31.00  Sold out

Beginner Small Orchard Package:  50 female cocoons and about 60 male cocoons, enough for our 49-hole Osmia Binderboard®.  Shipped in a small emergence box. (Binderboard® sold separately)
Osmia cornifrons  $75. 00  Sold out
Osmia lignaria        $96.00  Sold out

Intermediate Small Orchard Package:  approximately 100 female cocoons and 100 male cocoons, enough for our 98-hole Osmia Binderboard®.  Should provide pollination for about 1/3 acre of fruit trees.  Shipped in an emergence box. (Binderboard® sold separately)
Osmia lignaria      $175.00  Sold out

Advanced Small Orchard Package:  approximately 300 female cocoons and 300 male cocoons, enough for our 300-hole Osmia Binderboard®.  Should provide pollination for about an acre of fruit trees.  Shipped in an emergence box. (Binderboard® sold separately)
Osmia lignaria      $405.  Sold out

Professional Package, for large acreages:  Osmia lignaria only.  For 500 - 999 females (plus approximately equal numbers of males):  $1.25 per female.  For  1,000 or more females, (plus approximately equal numbers of males) $1.00 per female.  Sold out.

Shipping and handling additional.  Cocoons will be shipped priority or overnight mail depending on weather and time during the season.   Cocoons will be shipped with an ice pack.  Shipping and handling will be calculated when you contact us with your request.

Prices subject to change.

How to order