Native bees, of which there are over 3,500 in the United States, are important pollinators for backyard wildlife habitats. Their names are often indicative of their nesting styles. For example, mason bees use chambers of cement-like mud for their nest while digger bees construct nests in clay or sand banks. Yet, other bees are named after their traits such as the cuckoo bee. They lay eggs in the nest of other bees just like the cuckoo bird. Most native bees are gentle and solitary. One exception to this is our bumble bee (named from their humming sound while flying). It nests in a colony and can sting if provoked. If you want to watch a bumble bee clean itself and hear the humming sound.
Within the last ten (10) years, parasitic mites have devastated our wild honey bees causing a noticeable decline in backyard fruit and vegetable production. According to an article from the Oregon State University Extension Service in Douglas County entitled "Mason Bees As An Alternative," this devastation of honey bees is a nationwide problem. It's estimated that 30% of our food supply depends on pollination of a wide variety of plants by bees.
In another article, from The Xerces Society entitled "Why Care About Pollinator Insects," it says pollinators are keystone species in most terrestrial ecosystems; and like all wildlife, pollinators suffer as the landscape changes. There is a growing body of evidence that the loss, alteration, and fragmentation of habitats and the extensive use of pesticides have contributed to a decline in pollinator populations and reduced fruit set.
Attracting Bees with Native Plants
According to The Xerces Society, native plants are 4 times more attractive to bees than non-native plants. They also discusses heirloom varieties, planting in clumps, including plants with different colors and recommends having a diversity of plants. The following is a list of some of the recommended Oregon native plants:
- Aster - Aster
- Currant - Ribes
- Elder - Sambucus
- Fireweed - Chamerion
- Goldenrod - Solidago
- Huckleberry - Vaccinium
- Larkspur - Delphinum
- Lupine - Lupinus
- Madrone - Arbutus
- Mint - Mentha
- Oregon grape - Berberis
- Pacific waterleaf - Hydrophyllum
- Penstemon - Penstemon
- Rabbit-brush - Chrysothamnus
- Rhododendron - Rhododendron
- Salmonberry - Rubus
- Saskatoon - Amalanchier
- Scorpion-weed - Phacelia
- Snowberry - Symphoricarpos
- Stonecrop - Sedum
- Wild buckwheat - Eriogonum
- Willow - Salix
- Yarrow - Achillea
Some bees, like leaf cutters, blue orchards, and mason bees, nest in dead trees so leave dead standing trees on your property. If you don't have a dead stand, plant a log into soil to resemble a dead standing tree. Others, like miner and sand bees, are ground-nesting bees and require open bare patches of ground with sand or fine loam. Some bees, like mason bees and bumble bees, nest in man-made structures or bee houses. Bumble bees nest in a hole in the ground and frequently use abandoned mouse nests.
Bees, although attracted to many flowers, are very fond of blue and yellow flowers. Having different species of plants blooming during spring, summer and fall is important to their survival. Bees also need fresh water. A bird bath that is cleaned regularly is a good source.
Most native bees are solitary. The females construct nesting tunnels underground, in plants stems, or in wood. They provide the brood cells with pollen and nectar for the larvae. The eggs are laid on pollen balls inside the tunnel.
If you are interested in their life-cycle, The Xerces Society, has a number of must-reads for anyone interested in native bees. Another excellent source for information is Solitary Bees: An Addition to Honey Bees.
This solitary bee, the mason bee, is a gentle bee that has been a native pollinator for millions of years before the European honey bee arrived. They construct nests with walled-off chambers for each egg they lay; hence the name, mason bee. Mason bee habitat is wooded areas of North America and around homes.
The following is a list of Orchard Mason Bee (OMB) qualities from Solvangca:
The male OMB cannot sting and the female rarely does.
The OMB does not live in a nest like other bees. It lives in wooden blocks, but does not drill holes. It uses holes that are already made.
The OMB pollinates at a rate of 93% to 99% efficiency. The European honey bee is only about 3% efficient.
The OMB starts pollination at 55 degrees Fahrenheit. The European honey bee will not work at this low temperature.
The OMB will work during light rain and wind, whereas the European honey bee will stay in the hive.
It takes only 250 to 750 OMBs to fully pollinate an acre of fruit. It would take about 60,000 to 120,000 European honey bees to do the same job in the same time.
Each female is a queen and will produce as many as 50 eggs during a season before she dies, if there is a habitat available.
For more information on Mason Bees, Washington State University has a very informative article on Orchard Mason Bees with pictures of male and female bees, pictures of nesting blocks and an image of a filled orchard unit.
Crown Bees is an extensive mason bee resource. They have topics such as bee basics, FAQs, a section for the home gardner, commercial orchards, products, along with more information on helping you succeed including the topic called responsiblity.
Another excellent source on the Blue Orchard Mason Bee, Osmia lignaria discusses many details of their physical appearance, foraging behavior, nest sites and breeding behavior, brood development, developing your own osmia bee population, mud availability, pollen mites, and more.
Mason Bee Houses
There are many mason bee houses available for purchase. Some come with predator guards to help fend off woodpeckers and squirrels. If they don't come with a predator guard, place chicken wire, with a 1 inch diameter hole, around the front of the nest. If ants are a problem, Dr. Jim Cane from the University of Utah, uses a tennis ball cut in half and punctured in the center. The lower half of the tennis ball is filled with Tanglefoot®. The top half protects the bottom from filling up with water. Both halves of the tennis ball are skewered onto conduit pipe.
You can purchase an "Observation House" from Cozybee. By opening the lid, you can observe the mason bee's life cycle. You can watch larva feeding on top of the pollen ball, the adult female building mud plugs between every cell and bee larva busy eating the pollen lump. You can also observe bee development through the summer and fall until they spin cocoons and rest during the winter. Before moving bees out of the field, growers can use the observation nest to assess if larvae have stopped feeding to ensure safety in moving the nests.
If you are interested in building a mason bee house, the Cooperative Extension of Washington State University in King County has a fact sheets that you can download describing the life cycle of mason bees along with how to build and maintain houses. Studies show holes 5 3/4" deep produce the best female to male ratio. (Females live longer, are more active and do a better job of pollination.) Also, a clean 5/16" hole is the most attractive size for the female to use.
Provide landmarks for the bees so she can readily orient herself back to the nest entrance so she doesn't spend valuable pollinating time trying to find her nest site. Decorate the nest with a simple design such as single letters; i.e, L O V I X. Blue, pink or yellow are good colors. Making the straws or holes uneven also helps her to identify her site.
Even though bumble bees are native, they are not solitary bees. Like honey bees, they are social and live in colonies consisting of a fertile queen, sterile female workers, and males called drones. These social bees are the only bees to produce and store honey. And, unlike solitary bees who rarely sting, these social bees can readily sting to defend their colony. The largest North American colony of bumble bees on record consisted of 3,000 individuals.
Bumble bees can nest underground, in cavities along roots, or in tree cavities created by other animals. They like to nest in fiberglass insulation or abandoned nesting materials. Bird houses with abandoned bird nests and abandoned mouse nests are also used for nesting sites.
When blossoms first appear in early spring, the mated bumble bee queen emerges from hibernation. First, she replenishes her energy with nectar and then it is time to fine a summer home. Once she finds her nesting spot, she collects nectar and pollen and mixes them to form lumps of food. When the lumps are large enough, about the size of the first digit of a finger or thumb, she lays a cluster of eggs on it and buries the eggs near the surface. Next comes a 20-30 day brooding period. By vibrating her thoracic muscles, she generates heat to keep the eggs warm. Once they develop into larva, they feed on the pollen and nectar lump. Each larva transforms into a pupa and emerges as an adult bumble bee.
Young bumble bees stay at home until they mature and become foragers. This process can take from a few days to a week. The queen stays in the nest and lays more eggs while some of the workers help her with incubating the eggs.
In the middle of the summer, when the colony is large, new queens and drones are produced. In about a month, new queens emerge from the nest, feed on nectar and mate with the drones. Once drones emerge, they do not re-enter the nest. They spend the night on flowers or in foliage. Drones have abundant yellow hairs on their faces, lack pollen baskets and have longer antennae.
While the original colony dwindles and dies, the newly-mated queens hibernate in a cavity until spring when they start the cycle of life once again.
For more details on the life cycle of the bumble bee, check out The Bumble Bee Pages.
Bumble Bee Houses
There are a number of bumble bee houses you can purchase. If you want to build your own bumble bee house, don't use cotton-wool or surgical cotton as the bees tend to become entangled in the fibers. For their safety, use upholsterer's cotton. By the way, the first artificial bumble bee nests were made in 1887.
If you find a mass of bees hanging on a branch, please contact a beekeeper. They are very happy to capture swarms and give them good homes. Never kill the swarm with insecticides. Those 20,000 bees could have pollinated millions of plants and produced up to 50 pounds of surplus honey.
Don't confuse bees with the "Flower Fly." They have one pair of wings; bees have two. And, flower flies don't accumulate pollen on the undersides of the abdomen and legs like bees do.
If you are interested in honey, there is a great website An Expert's Guide to All Things Honey where you will find information on Honey Making, Honey Facts and Trivia, Honey Recipes for Kids, and Teacher Resources.
Insecticides & Pesticides
Bees are extremely sensitive to many commonly applied insecticides. Please do not use them. If you have to spray, apply organic sprays and apply them in the evening when bees are less likely to be active. Pesticides contaminate blossoms, nectar, pollen, soil and water. Honey bees have lost at least 20% of their population from pesticide poisonings. Check out Natural Pest Controls to find alternative sources for the problem.
The Xerces Society
Donate to The Xerces Society for Invertebrate Conservation, an international nonprofit organization dedicated to protecting biological diversity through invertebrate conservation, and receive their popular magazine Wings.