Did you know there are species of bees that build their nests in the ground?
While you’re probably familiar with honey bee hives or wasp nests, ground bees have very different nesting habits. Instead of using materials to construct a hive, they will build nests in the soil or other loose ground.
If you’ve ever wondered where the bees in your yard live, it could be underground! Read this article to learn more about ground bees and why they’re such interesting insects.
What Are Ground Bees?
Ground bees are also known as ground-nesting bees or ground-dwelling bees. All of these names refer to a group of bee species and not one single type of bee. These species are characterized by building their nests into the ground but can otherwise have many differences.
They’re more common than you might think. About 70% of the 20,000 bee species are ground-nesting bees. Some species you’ve probably encountered in your lawn or garden include bumble bees, sweat bees, and cellophane bees.
Since they’re such a varied group of insects, ground bees can be found worldwide. The exception is cold climates, especially places that don’t get warm summer temperatures.
Physical Characteristics of Ground Bees
There are so many species of ground bees, and they don’t all look alike.
For example, bumble bees are large and instantly recognizable with black and yellow hairs. Sweat bees are very small, almost resembling flies, and can be an iridescent green color. Cellophane bees more closely resemble honey bees.
While all three species are completely different-looking bees, they’re all considered ground bees because of their nesting methods.
Ground Bee Behavior
Ground bees can either be solitary or social.
Solitary bees build their nests, lay their eggs, and forage without division of labor. Social bees live in an organized colony and usually have specific tasks for each individual to contribute. This includes a single fertile queen who lays all the eggs.
Most ground bees are not aggressive and will likely retreat rather than confront humans and other animals. You only risk a sting if you step on them or they feel trapped. Solitary species that don’t live in colonies are even less likely to attack.
Ground nesting bees are generally most active for three to four weeks, but different species will likely be active during warmer months. Many of their life cycle happens underground as they develop into adult bees.
Ground Bee Nests
Ground bees will either dig their tunnels or find existing holes in the ground to use. They generally prefer soil that is loose, dry, and sandy with sparse vegetation. In general, holes will be a quarter to half an inch in diameter.
Each tunnel usually has a chamber at the end to store pollen and nectar to feed the brood. Most ground bees will excavate a tunnel, add pollen and nectar, lay a single egg on top, and seal it off before repeating the process until the tunnel is filled.
This ensures that the developing bees inside have all the nutrients they need to survive the winter until they emerge fully grown in the spring.
Ground bee nests will look different depending on if the species is solitary or social. Social ground bees will connect their tunnels to allow the bees to move around throughout the entire nest. They have a queen who overwinters, so she can continue reproducing the next year.
Solitary nests will often be nearby other nests but are not connected and don’t tend to interact at all. These ground bees typically fill a tunnel and then move on to a new nesting site to repeat the process.
How Ground Bees Impact the Environment
Ground-nesting bees are native species, meaning they are adapted and integral to the ecosystems in which they live.
They are also considered some of the most effective pollinators out there. As they go from one flower to another collecting nectar and pollen, they distribute the pollen among plants. This is how these plants can reproduce.
Since ground bees are present around the world, they contribute to the pollination of a huge number of plants.
Certain species of ground bees are important in pollinating specific plants. One example is mining bees, which play a major role in pollinating fruit trees.
Signs of Ground Bees
Ground bees are inoffensive in terms of their impact on the landscape. You may notice small holes in the soil near your home and occasionally spot a bee entering or exiting.
Otherwise, there aren’t many clues that they’re nesting nearby. Even if you see one flying around, it may not mean their nest is nearby.
Should You Be Worried About Ground Bees?
Generally speaking, ground bees don’t pose any real threats to humans and aren’t usually considered pests that must be exterminated.
Unless you notice a lot of activity and many holes with bees going in and out in a high-traffic area, you probably won’t have any problems.
If you want to deter them from nesting in certain spaces, there are a few simple things you can do. No matter what, avoid using pesticides.
Agitating the soil and packing it down firm will lead them elsewhere. Blocking their access to soil with organic matter like fertilizer and mulch or spreading pea gravel and other material will also be unappealing to them.
You can plant more vegetation so they don’t have an open space to start digging into. Ground-dwelling wasps can be more of an issue, and several species nest this way. Before you take action, try to determine what you’re looking at.
Unlike ground bees, wasps and hornets tend to be much more aggressive and will often sting with little to no provocation. It’s best to consult a professional to avoid being attacked if you need them gone.
Threats to Ground Bees
Many species of ground bees are dwindling, which can lead to serious problems getting food on our plates.
Bees are responsible for pollinating most of the flowering plants on the planet. Without them, it would be impossible for these plants to reproduce.
Pesticides represent one of the main threats to ground bee populations. Pesticides and insecticides don’t differentiate between types of insects, so while you may be trying to get rid of something else, the ground bees will be susceptible too.
If you must use them, try to avoid doing so when nearby plants are flowering and only apply them in the spots that need them. Since they nest underground, they can be harmed by spraying chemicals.
Climate change and habitat loss have also negatively impacted ground bees. While they’re happy to build their nests in your yard, designating lawn space over other flowering plant space means they’ll have fewer resources available.
How You Can Help Ground Bees
There are so many easy ways to support ground bee populations.
A well-manicured lawn doesn’t provide the pollen or nectar that ground bees need. Instead, use that space for native plants, a vegetable garden, wildflowers, fruit trees, or shrubs.
Avoid using mulch, or at least leave an area free of mulch for the bees to use.
Leave the leaves! Resist raking leaves in the fall, as they help insulate overwintering bees. Disturbing fallen leaves too soon in the spring can harm developing ground bees that haven’t emerged yet, so it’s best to wait until late spring or early summer.
Encourage your friends, family, and neighbors to do these things to create more pollinator-friendly areas. It’s also important to support local, national, and global conservation efforts to ensure ground bees are protected now and in the future.
Ground Bees Are an Important Part of the Environment
Ground bees are really not species you need to fear.
They’re very beneficial to have around, and they don’t pose a threat to humans the vast majority of the time. You may even have ground bees nesting in your yard regularly without realizing it.
This is one species we need to be able to coexist with peacefully, and we must do everything we can to make sure they’re around for a very long time.
Want to learn more about hard-working bees? Like ground bees, honey bees are another fascinating pollinator!