Where and How do Native Bees Nest?

You may be familiar with honeybees, and how they have been declining in population lately. However, you may not be aware that honeybees are actually a European import! 

North America has a huge diversity of native bees. You may have seen them without realizing it – In our yard, I’ve seen black Mason Bees, little green Sweat Bees, striped Leafcutter Bees, and of course Bumblebees. These bees, along with many more I haven’t even mentioned, actually do the bulk of the pollinating on this continent! 

Seeing all these bees leads to a question – Where do they all nest? 

While European Honeybees sometimes will start wild colonies in hollow trees and sheltered crevices, our native bees are mostly Solitary Nesting, meaning that one queen raises one nest, doing all the work herself. These solitary nesting bees nest in hollow plant stems, tunnels in wood and burrows in the ground. We also have native Bumblebees, which are social bees – They nest in a colony with a queen and workers, prefering old rodent burrows or piles of fallen plant debris.  Each type and species of bee has a unique nesting preference, and knowing this can be very helpful if you are wanting to support our native bees. 

Types of Native Bees 

Of our native bees, there are three types of nesting habits. While North America is home to nearly 4000 species of native bees, they fall into these three categories: Solitary Ground Nesting Bees, Social Bumble Bees, and Solitary Wood Nesting Bees. 

Solitary Ground Nesting Bees 

Most of our native bee species in North America – Roughly 70% – fall into the Solitary Ground Nesting Bee category. These bees excavate burrows in the ground, making small chambers known as Brood Cells where they lay their eggs. 

Nesting in small, narrow burrows in the ground means that these bees need undisturbed, uncompacted bare soil to be able to nest – Usually in a sunny South or West facing area. A typical habitat for these bees might be a sunny bank of sandy soil with scattered plants and plenty of bare soil. 

While gardeners may not like seeing bare soil in their garden, it is important to leave a few places in your landscape for these bees. In our vegetable garden, I have started doing more and more no dig gardening, relying on cover crops to protect the soil. As a result, I have noticed a proliferation of squash bees, which are a native solitary ground nesting bee! This means plenty of zucchini, pumpkins and squash from our vegetable garden, all thanks to a small native bee that nests in the ground. 

Solitary Wood Nesting Bees 

Solitary wood nesting bees make up just under 30% of our native bees. These bees nest in tunnels in wood as well as pithy plant stems – While solitary wood nesting bees are in the minority of total species, they are one of the most common to see in your garden, especially if you put out Bee Houses/Bee Hotels for native bees. Different species prefer different diameter tunnels, so it’s worth doing your research when selecting a bee hotel to find out what species you’re going to attract. 

Related: What Size Bee House Should I Get? 

One type of wood nesting bee is the Mason Bee, a tiny black bee that is an incredibly efficient pollinator of fruit trees. For this reason, many orchards keep mason bee houses around their grounds, ensuring a plentiful crop. 

Another common wood nesting bee is sweat bees – These small green bees are excellent pollinators, but they do have a liking for sweat! I often find them on me when I’m working outside in the summer, but I haven’t been stung by one in years. Their stings aren’t that painful, but they do itch for a while! 

Another solitary wood nesting bee is the carpenter bee – This is probably the only native bee that can truly be a nuisance, excavating large burrows in wooden structures. This is the only bee that I set out traps for, as they can cause a lot of damage in the spring when they’re excavating their nests. 

Bumble Bees 

Of all the native bees, social Bumble Bees have the least number of species. These bees nest in a colony with a queen and worker bees, nesting in old unused rodent burrows, leaf and brush piles, and sometimes even old bird nests. In plains areas, the preference is standing clumps of native bunchgrasses such as Little Bluestem and Indian Grass. 

Bumble bees are one of the most useful native bees for agriculture, and you can even purchase hives of them for greenhouse culture! Our family raises greenhouse tomatoes, and we have hives of bumble bees in each greenhouse to aid pollination. 

Making Your Garden Bee Friendly 

With all these thousands of bee species threatened or in decline, it is so important to make sure you’re doing your part by adopting sustainable landscaping practices in your garden! While it is a great gesture to put up a bee hotel or two, look around your yard – Do those bees have enough to eat? Is there enough shelter for bees that don’t use bee hotels to nest? 

Plant Pollinator-Friendly Flowers 

Many of our native bees are Specialist Pollinators, meaning they can only raise the next generation if their specific pollen preferences are available. A good example is the Squash Bee I mentioned earlier – These bees can only feed on the pollen of squashes and cucumbers. Another specialist pollinator are sunflower bees, which only feed on pollen from plants in the Aster family. 

Ensuring you have a diversity of plants in your garden, with something in bloom throughout the growing season, goes a long way towards supporting native pollinators. Including specific plants for specialist pollinators is another way you can help. Look up your area Xerces Society or National Wildlife Federation, they are an excellent tool for recommendations on plants for your area. 

Adopt Bee-Friendly Landscaping Practices 

Are you the type of gardener who is constantly tidying your garden, removing every last twig and leaf as soon as it falls? Or maybe you cut your garden back to the ground every year, not really paying attention to the season? Taking on a slightly more hands-off gardening approach, and paying attention to time and season, can really give your garden a sustainability boost. 

Many of the wood nesting bees utilize old hollow plant stems from perennials and caney shrubs – When cutting back your garden, leaving 6 to 8 inches of stubble gives these bees a nest site. Once everything grows up, you don’t see the stubble anymore anyways. Also, waiting until spring to cut back gives the bees a good place to overwinter, and the standing plant matter does a great job of trapping leaves that blow around. 

We live in the countryside, surrounded by cornfields, and the few houses along our street all have the typical “suburban” sterile landscape of turf grass, callery pears and yews.  In the colder months, the wind really blows – I notice that even though we don’t have many garden beds, the few we do have trap leaves from trees we don’t even have in our yard! It’s basically a free way of trapping nutrients, as tree and shrub leaves are one of the best garden soil amendments. 

Back to the bees – Again, leaving those clumps of perennials and grasses over the winter gives good shelter and nesting sites for these bees – One of those bee hotels might have up to 100 openings, but a bed of perennials is going to have thousands of openings for bees to nest in! 

Another thing to do is to go easy on the wood mulch – Ground nesting bees need bare soil to nest in, so make sure you’ve got at least a little bare soil in drier, sunner parts of your yard. Wood mulch, applied year after year, is completely unnecessary – Around here, I see mulch applied 6 inches deep, right up around the base of trees in the classic “Mulch Volcano” – Why anyone even thinks this looks good is beyond me! I might use a small layer of wood mulch the first year I plant a bed, but after that, plants are the mulch and the only thing that gets added to the soil is the organic material that is produced by those beds. 

Take on these practices, and observe what happens – Your bees will thank you!