Credit where credit is due: Honeybees aren’t the only bees in the garden

By Julie Banken
WSU Chelan/Douglas County Master Gardener

Bee on a flower.
A leafcutter bee cuts pieces of petals to line her next. – Provided photo/Lisa Robinson
Bee tube nests.
Resin bees, leafcutter bees and mason bees filled these hollow reed stems with insulation materials and provisions of pollen for their offspring – Provided photo/Julie Banken
Julie Banken
Julie Banken – WSU Master Gardener intern – Provided photo/WSU Master Gardeners

There are three main ways to be a bee. Honeybees live social lives and share the work of raising young and gathering food to sustain their colonies. Queens lay eggs and workers divide all the labor. Even in winter, their hives remain busy, crowded places, literally buzzing with the activity of thousands of workers.

Bumble bees also live in colonies, but unlike honeybees, their social life comes to an end at the onset of winter. All bumble bees in a colony die in fall except the mated females. These future queens dig shallow burrows and spend the winter underground in a dormant state. In the spring, each new queen, or “foundress,” will establish her own nest, lay eggs, and nurture the first generation of daughters that will help her with foraging and caring for subsequent broods.

Fewer than one out of 10 bees are social. The other 90% are solitary bees, and as their name implies, they spend their entire lives on their own. They serve no queen and do all their work alone.

Males typically don’t live long after mating, but female solitary bees have an extensive to-do list. In the spring, they choose nesting sites, construct nurseries, gather nesting materials, lay eggs, and provision egg chambers with pollen. The one thing they don’t have to do is take care of their babies. Once their eggs are safely tucked in, the females’ work is done.

Solitary bees don’t make honey or combs of wax, but they are incredibly creative when it comes to building nests. Remarkably, over two-thirds of solitary bees nest underground. Mining bees and digger bees are good examples. These small insects that we typically see in flowers also dig burrows that can range from a few inches to several feet deep.

The rest of the solitary bees are cavity-nesters. They build their nests in hollow plant stems and holes they find in dead wood. Starting at the back of the hole, they add pollen and an egg, then seal them up together, repeating this process until the hole is filled. If you could open it up, the completed nest of a cavity-nesting bee would look like a colorful pollen parfait.

Cavity-nesting bees are particular about the materials they use to seal each brood chamber. Mason bees use mud, and resin bees use sap. Leafcutter bees are the best interior decorators; they line and seal their nests with a quilt of carefully cut pieces of green leaves or colorful flower petals.

Tips to help native bees in your yard

Whether they are social, annually social or solitary, all bees pollinate flowers as they forage for food. Unfortunately, not all bees get the credit they deserve for the vital role they play in plant reproduction. Honeybees may be the most iconic pollinators but are actually not native and have spread across North America like dandelions. Despite threats from pesticides, diseases and parasites, thanks to their importance to the crops we depend on for food, there are more honeybees in the world today than at any time in history. To put it simply, honeybees are hogging the resources. It is the native bees that need our help.

The best way to help native bees is to provide them with places to live as well as food to eat. When flowers have faded, there are still things you can do to make your yard “bee-friendly”:

  • Leave the leaves that fall in flower beds to provide shelter and habitat for ground dwellers.
  • Leave rodent holes, too. Bumblebees love to build nests in holes that come pre-lined with fur.
  • Add logs, rock piles, and sandy areas to your garden to create nesting sites that will be ready for bees when they emerge in the spring.
  • Allow some dawn-facing, bare patches of soil to remain undisturbed and uncovered. Tilling and covering the ground with landscape fabric or thick layers of mulch prevent ground-nesting bees from emerging.
  • Save the stems on perennials that die back in the winter. Let flowers go to seed for birds and other insects, then old stems will be ready for cavity-nesters to move in when they emerge in spring. Vegetation will grow up and hide the dry stems, and a new generation of bees will emerge to pollinate its flowers.
  • Keep your yard chemical-free so bees have healthy nesting places to raise their young. Many herbicides and systemic insecticides can persist in soil or vegetation for months or even longer.

A WSU Chelan and Douglas County Master Gardener column appears weekly in The Wenatchee World. To learn more, visit bit.ly/MGchelandouglas or call (509) 667-6540.