Native Bees: Pollinate Native Plants, Fruits and Vegetables

While raising monarch butterflies in her Round Lake backyard, Pam Wolfe began learning about some much lesser-known and tinier insects—native bees. She’s seen a green sweat bee visiting native goldenrods, asters and ironweed, and a squash bee visiting her vegetables.

        “Native bees are the unsung heroes of pollination,” says Wolfe, a member of Wild Ones (WildOnes.org), which promotes using native plants. “People are concerned about honey bees declining, but they should also be thinking about and helping the native bees.”

        Native bee numbers are declining both in the Chicago region and nationwide. A Center for Biological Diversity (BiologicalDiversity.org) study has shown that nearly 25 percent of the nation’s native bee species are at risk of extinction.

        Honey bees, which European settlers brought to North America in the 1600s, contribute nearly $20 billion to the value of U.S. crop production, according to the American Beekeeping Federation (abfnet.org). Their numbers have been declining due to reasons being researched by agriculturists.

        But scientists are also focusing on the decline of native bees, which pollinate various crops such as blueberries and cranberries, as well as a host of native plants that provide food and shelter for other wildlife. Some native bees are capable of “buzz pollinating” plants, something honey bees cannot do—by rapidly moving their muscles to shake pollen loose from a plant.

        Laura Rericha-Anchor, a wildlife biologist with the Cook County Forest Preserves (fpdcc.com) and a research associate with the Conservation Research Institute (ConservationResearchInstitute.org), notes her research is finding that some native bee species in the Chicago region are as common as they were 100 years ago, but others are quite rare or not being seen any longer. “Their numbers are declining due to pesticide, fungicide and herbicide usage, as well as habitat loss, climate change and the introduction of non-native bees,” she says.

        “A grand symphony occurs with bees,” says Rericha-Anchor. “Bee species have synchronized their emergence from the ground with the blooming time of certain plants. But with the gradual warming we are observing, some bee species are emerging and their host plants are not available because they’ve already bloomed. If climate change predictions are correct, within 100 years, we will not only lose many of our native bees, but also the native plants they pollinate.”

        She is writing a book-length scientific paper on the 483 bee species that occur in 53 counties near the southern tip of Lake Michigan in Wisconsin, Illinois, Indiana and Michigan. Many are native to the Chicago region.

        One declining species is the rusty-patched bumblebee. Once fairly common in the Chicago region, this bee’s population has declined by 87 percent in the past few decades, and is now listed as a federally endangered species. Like other native bumblebees, the rusty-patched requires plants that provide both nectar and pollen, underground nesting sites and hibernating areas for queen bees. Rusty-patched bumblebees are easy to identify if seen closely. The worker bees display a rusty patch in the center of the yellow hairs on their abdomen. Many other native bees are difficult to identify to species without the use of a microscope.

        The most common native bees are placed into groups such as bumblebees, sweat bees, mining bees, carpenter bees, cuckoo bees, leafcutter bees, mason bees and plasterer bees, according to the Illinois Department of Natural Resources (dnr.Illinois.gov).

        Bees belong to the order Hymenoptera – all of which have hairs on parts of their body. Their life cycle includes eggs, larva, pupa and adult. They live in varied habitats including near wetlands, grasslands and suburban and urban yards. About 70 percent of the Chicago region’s native bees live in the ground, each with different life cycles. The rest of the species, about 30 percent, nest in holes such as hollow stems, dead wood and rock crevices.

        Native bees can be smaller than a pinky fingernail or as large as a thumb. Some are solitary; others are communal and somewhat social. The bees seen in yards and neighborhoods are mostly generalist species, meaning they can find more than one plant to gather pollen and nectar. Other native bees require specific soil types, such as sandy dune lands. Some will only gather pollen from specific plants or those in certain families. “Then you have a cohort of bees that specialize only on the pollen of that plant, and only the nectar for another plant,” Rericha-Anchor says.

        People that live near high-quality remnant woods, prairies and other ecosystems might help the specialists by planting what they need. But anyone can help bees, no matter where they live. “We should do whatever we can to increase the amount of resources available to bees—pollen and nectar—and eliminate the biological desert of green grass,” Rericha-Anchor says. “Since each species has a different life cycle and timeline, it would be great if gardens had flowers blooming all season long, from early spring to late fall.”

        Two easy spring-blooming plants to grow for bees are wood betony and Virginia bluebells. Shooting stars and wild indigo also attract native bees. For summer bloomers, Rericha-Anchor suggests pale-leaved sunflower, black-eyed Susan, coneflower and butterfly weed. To attract native bees in late summer and fall, plant goldenrod and asters.

        Rericha-Anchor has maintained a small perennial garden in her Elk Grove Village yard for 20 years. In that time, she’s documented 30 species of native bees. She also uses no chemicals because many can cause neurological dysfunction in bees.

        Of course, bees do sting, but typically the native ones aren’t aggressive unless someone steps on their nest. “Only females have stingers, and many species are too small to affect humans or penetrate skin,” Rericha-Anchor says.

          To learn more about native bees, Rericha-Anchor suggests visiting the Morton Arboretum (MortonArb.org) where she has documented more than 100 species.

         Rericha-Anchor says nature lovers might enjoy sitting near flowers in summer and watching for native bees. “You don’t have to know what the species are,” she says. “You can just note that one collects its pollen on its abdomen, another on its leg. Or here’s a metallic-colored bee. Here’s a black bee. Then you become more in tune with nature and more responsible about caring for it.”

 

Ways to Help Native Bees in the Back Yard

• Eliminate pesticide use.
• Create a garden with native plants that provide nectar and pollen to bees from spring through fall.
• Reduce lawn space and mow less often.
• Leave some broken branches for cavity-nesting bees.
• Build or purchase and erect a bee box, although the boxes might also attract non-native bees.

 

Visit Facebook.com/nativebeeawareness to learn more about the native bees of the Greater Chicago Region and what can be done to help these pollinators.

Sheryl DeVore is the author of several books and hundreds of articles on nature, the environment and health. She can be reached at [email protected].