Have you seen bees burrowing in the soil of your lawn or garden? As it turns out, not all bees live in hives or make honey. There are 20,000 species of bees, and 70% of them nest in the ground!
Just like honey bees, ground-nesting bees are important pollinators. Digger bees you may not have heard of include sweat bees, mason bees, and miner bees. These solitary bees nest in the ground, so many people don't know that they exist!
If you're wondering which bees live in the ground, here's what you need to know about these elusive creatures.
What is a Ground Bee?
Ground bees are typically solitary insects that, unlike other bees, don't live in colonies. This means that each female bee builds her own underground nest. Often, many female bees will build nests next to each other, which is called gregarious nesting.
Male ground bees hover around the nests in search of a mate and do not live as long as female bees. You will notice that there are more bees flying around ground bee nests in the early spring as males look for females to mate with.
Many bees that live in the ground don't make honey like their colony nesting cousins. Instead, they feed each baby bee with pollen and nectar gathered from flowers nearby. Ground bees are like single mothers, working hard to bring food to their young every day.
How do I Identify a Ground Bee Nest?
Ground bee nests look like a small hole in the ground, surrounded by a circular pile of dirt. This is from bees excavating the soil to create bee burrows where they can live and lay eggs. The entrance hole can be as small as a pencil tip, but it's still easy for these tiny burrowing insects to get in and out of their homes.
A ground-nesting bee will usually prefer dry soil conditions with morning sun exposure. This is why you often see them nesting in bare patches of well-drained soils between sidewalks and grass.
Other ground bees nest under fallen leaves and in existing holes in dead or fallen wood. This is one reason it's important to not clear all of the leaves off of your lawn - you might be removing a bee's home!
Do Ground Bees Sting?
Ground bees are not aggressive bees, and will only sting if they feel threatened, which is rare. Because most ground bees don't form colonies like other bee species, they don't have a hive to protect. Male bees cannot sting, while most female ground bees have a stinger but will not sting humans unless they are handled.
The exception to this is yellow jackets, which are often confused for bees but are actually wasps that live in underground nests. These insects will sting in order to defend their colony. However, yellow jackets are still important pollinators.
If you're out in nature and notice bees buzzing around your feet or see small holes on the ground, you may be near nest sites for ground bees. Bees that live in the ground are important pollinators for many of our favorite fruits and vegetables, so be careful when mowing your lawn or working outside to not disturb them.
Types of Ground Nesting Bees
Sweat bees are very small bees that are non-aggressive. Most are banded with brown, black, or yellow, but some have beautiful green or blue metallic coloring.
These insects prefer to nest in fallen logs or on flat ground surfaces near flowers for easy access to food.
Mason bees are important pollinators for many fruit trees, so they are also known as orchard bees. They are a solitary species, so they do not nest in colonies.
These ground nesters create doors to their nests with clay, which is why they've been compared to masons.
It's common to mistake a miner bee for a bumblebee because their body shape and coloration are very similar. Both are seen frequently during the summer months.
Female mining bees will build a tunnel-like structure for their nest in clay soils. This is why miner bees are sometimes also called chimney bees. You may see a grouping of tunnel nests near each other, despite the bees being solitary.
Leafcutter bees are known for their amazing pollination skills. They can pollinate ten times more flowers in a day than honeybees!
These ground-nesting bees prefer hollow plant stems, rotten wood, or soft soil where the female builds her nest and lays her eggs. She'll use pieces of leaves she has cut to line the walls of each chamber in her nest, and seal the entrance.
There are over 250 species of bumblebee worldwide. Bumblebees have a more typical colony structure than most ground bees, with a queen and worker bees. Unlike honey bees, they do not make or store a lot of honey.
Bumblebees prefer to nest in old burrows created by rodents such as mice. During the spring and summer, the bumblebees work together to collect nectar and pollen and to raise worker bees. During the winter, the colony decreases in size, and the queen burrows back into the ground to wait for spring.
Yellow jackets aren't actually bees, they belong to the wasp family. Similar to bumblebees, yellow jackets commonly nest in abandoned rodent burrows. They also live in colonies, with a queen and workers.
Yellow jacket nests are made of paper pulp that the insects create from saliva and wood. If you disturb one of these ground nests, yellow jackets can be aggressive and may swarm and sting. They get particularly defensive of their nests in the fall.
Bee happy about ground bees
Ground bees may be tiny, but they're very important for pollinating plants in our fields and gardens! If you see ground bees in your front yard or back garden, be sure not to disturb them. They'll ensure that more flowers bloom year after year.
Most bees living in the ground are very docile and prefer not to sting humans if possible. You shouldn't use pesticides on nesting areas to get rid of ground bees. Not only are they harmful to the bees, but pesticides can also be toxic to other animals and even humans.
Since ground-nesting bees prefer to burrow in dry soil, watering the ground in an area you do not want them to nest can safely encourage them to move elsewhere without hurting them.
Bees that live in the ground play a vital role in our ecosystem, so be sure to "bee happy" about them!