Honey bees, imports from Europe, are important – critical pollinators of 30 percent of the crops Americans eat, but it’s the thousands of native species – solitary, stingless, ground-nesting bees that are far more efficient pollinators and perhaps more imperiled.
Coming to their aid in local gardens, ecological science meets whimsy in wooden shelters called ‘pollinator houses.’
A late summer morning on a quiet street in Blacksburg, a blue jay is yelling from an old black cherry tree, a squirrel is munching scarlet dogwood berries and Sandy Weber is waist deep in shaggy blue blossoms of wild ageratum talking about her pollinator house.
Pollinator houses, shelters for bees, butterflies, ladybugs and bats, some rustic, some sleek, first became popular in European gardens. In recent years, as concern grew for the declining populations of honey bees, awareness grew around the importance all pollinators in the US,” said the Xerces Society, the prominent environmental organization dedicated to raising popular awareness of pollinators.
Weber’s pollinator house is both whimsical and handsome at the same time. It’s a simple wooden box set in a mound of ageratum stacked tidily with what looks like sticks and pinecones. A tiny sign on the front says, ‘Bug Hotel: Vacancy.’
“They’re very simple to build,” she said. “I got the wooden box at the thrift store for a dollar.” The roof is a slab of slate “to keep the deer for knocking the whole thing over.”
Already interested in biological sciences, Weber learned about her garden’s role in supporting native pollinators through Master Naturalist entomology lectures.
Timothy McCoy, Extension Associate with the Virginia Tech Pesticide Programs, gave those lectures about native and solitary bees
“As more people are coming to understand that pollinators like honey bees need our help, native bees are all around us and need our help too,” he explains.
“I encourage everybody to put out solitary bee houses,” McCoy said. “It’s easy. Solitary bees are incredibly opportunistic. If you’ve got a pollen source, flowers or trees, a nesting location, and proximity to water. It’s pretty effortless.”
“I don’t want to choose ‘who’s more imperiled’,” McCoy said.
Honeybees are a managed livestock, so we know what their numbers were and what they are now. But not much is known about solitary bees numbers.
“They’re more susceptible to the same kinds of things honey bees are, but those dangers are more devastating to native bees – viruses carried by to flowers the consequences to solitary bees are worse – It’s just them. They’re all by themselves.”
There are 4000 species of native bees, they come in all sizes seeking all kinds of nests.
Weber focuses on Mason bees, also called Blue Orchard bees for their metallic blue bodies, like to lay their eggs in tubes.
The bee goes in the tube stuffs pollen balls in there sometimes with a little earth, so there needs to be bare soil nearby. There’ll be a row of bee eggs and pollen balls in the tube. That’s in late summer – now, really. Then she dies, but the larvae grow in the tubes. There’s pollen for them to eat all winter. Then they come out in the spring – when the peaches are blooming. They really like redbud blossoms.”
Weber made tubes for mason bees. “I drilled holes in little logs – 5/16″ diameter, and 6″ deep. I rolled up corrugated cardboard and added pinecones and there’s a brick.” The house provides a haven for egg laying, nesting, and weathering winter storms.
Vertical slots invite butterflies to roost, horizontal slots attract lacewings, and holes attract ladybugs who eat garden pests like aphids.
McCoy advises to be sure to clean the pollinator house well each season so disease and parasites don’t move in causing more harm than good.
Walking through the pink and purple autumn blooming flowers of Weber’s yard, she said, “This is maybe not the best location – it should be in a more protected spot, but I wanted to raise awareness of my neighbors and people going by.”
For more information on pollinator houses, visit www.crownbees.com or www.virginiamasternaturalist.org.