Most people envision wasps as terrifying, territorial, yellow and black bugs, that are good for nothing, except stinging people and being generally angry. While there are territorial, stinging wasps, they make up a very small percentage of wasps, and often give other wasps a bad rep. The truth is, wasps are very important. They are responsible for regulating insect populations, seed dispersal, decomposition, and are even important pollinators. But before we get into that, we should go over what a wasp is.
What is a wasp?
Wasps are insects belonging to the insect order Hymenoptera, the second most diverse group of organisms in the animal kingdom. The order Hymenoptera contains over 150,000 species, and wasps account for about 103,000 of those species.
Wasps are often called bees, but this isn't true. The two are related, but both bees and ants actually evolved from wasps, about 140 million years ago. At-present, there are two different categories wasps are classified into: Aculeata (stinging wasps) and Parasitica (Parasitoid) wasps.
Wasps are insects belonging to the insect order Hymenoptera, the second most diverse group of organisms in the animal kingdom. The order Hymenoptera contains over 150,000 species, and wasps account for about 103,000 of those species.
Wasps are often called bees, but this isn't true. The two are related, but both bees and ants actually evolved from wasps, about 140 million years ago. At-present, there are two different categories wasps are classified into: Aculeata (stinging wasps) and Parasitica (Parasitoid) wasps.
Parasitica - Parasitoid Wasps
Parasitoid wasps occupy about 70% of the total wasps species, and contain a wide, and diverse variety of wasps, which vary from less than 1mm long to over 150mm long (that's over 5 inches!). All parasitoid wasps are solitary and nest individually. These wasps are called parasitoid because they need to kill another arthropod (invertebrates such as insects, arachnids or crustaceans), to complete their life cycle. Parasitoids are separate from parasites, as a parasite is an organism that lives in or on a host, but does not kill the host, and a parasitoid is an organism that lives in or on the host, and kills their host organism. Parasitoids are also separate from Aculeate, as they do not have stingers. Instead of stingers, parasitoid wasps have an ovipositor. An ovipositor is a modified egg laying device that can inject eggs, as well as venom, into a host organism. Many ovipositors also have the ability to dig or drill into substrate, as many potential hosts are wood boring, or underground insects. While this may sound potentially terrifying, most parasitoids are unable to harm humans, and as their ovipositor used mainly for reproduction, and is only used for defense in extreme situations.
A parasitoid's life cycle is eerily similar to that of the xenomorphs' in the alien franchise. The xenomorph larvae (face-hugger) must kill its host (space marines) in order for larvae to pupate (chest-burster). In parasitoid wasps, the female, adult wasp will start by paralyzing, and injecting an egg, into or onto a host arthropod(s). Then, the wasp's larvae will hatch and devour the host(s) (often times alive) in order for the larvae to grow, molt, and pupate. Eventually, resulting in a fully grown, adult wasp. Despite this grim start to life, adult parasitoid wasps do not eat other insects and, like bees, primarily eat nectar.
Parasitoid wasps occupy about 70% of the total wasps species, and contain a wide, and diverse variety of wasps, which vary from less than 1mm long to over 150mm long (that's over 5 inches!). All parasitoid wasps are solitary and nest individually. These wasps are called parasitoid because they need to kill another arthropod (invertebrates such as insects, arachnids or crustaceans), to complete their life cycle. Parasitoids are separate from parasites, as a parasite is an organism that lives in or on a host, but does not kill the host, and a parasitoid is an organism that lives in or on the host, and kills their host organism. Parasitoids are also separate from Aculeate, as they do not have stingers. Instead of stingers, parasitoid wasps have an ovipositor. An ovipositor is a modified egg laying device that can inject eggs, as well as venom, into a host organism. Many ovipositors also have the ability to dig or drill into substrate, as many potential hosts are wood boring, or underground insects. While this may sound potentially terrifying, most parasitoids are unable to harm humans, and as their ovipositor used mainly for reproduction, and is only used for defense in extreme situations.
A parasitoid's life cycle is eerily similar to that of the xenomorphs' in the alien franchise. The xenomorph larvae (face-hugger) must kill its host (space marines) in order for larvae to pupate (chest-burster). In parasitoid wasps, the female, adult wasp will start by paralyzing, and injecting an egg, into or onto a host arthropod(s). Then, the wasp's larvae will hatch and devour the host(s) (often times alive) in order for the larvae to grow, molt, and pupate. Eventually, resulting in a fully grown, adult wasp. Despite this grim start to life, adult parasitoid wasps do not eat other insects and, like bees, primarily eat nectar.
Aculeata - Stinging Wasps
Aculeate wasps, also known as stinging wasps, occupy about 30% of the total wasp species, and contain both social and non-social wasp species. These wasps are classified as stinging wasps as their ovipositor has been modified, over time, into a defensive tool, that we now call, the stinger. This is also why only female wasps have stingers, as only female wasps have ovipositors and can lay eggs! Non-social aculeate are exactly as they sound. They live in individual nests, and fend for themselves. However, these non-social aculeate wasps also engage in parasitoid behavior, except these wasps can only lay eggs onto a host, and not into a host, as they lack the specialized ovipositor that other parasitoid wasps have. They may also provision their nests with additional hosts for their larvae, while the adults consume mostly plant nectar. These solitary wasps account for about 97% of aculeate wasps, with the remaining 3% accounting for the social wasps that most people are familiar with (i.e. paper wasps, hornets, and yellow jackets). These wasps live in colonies with a queen and a cast of workers, and can often be aggressive and territorial. Social wasps also provision their young with prechewed arthropods. Adult social wasps feed on a wide variety of arthropods, as well as nectar.
Aculeate wasps, also known as stinging wasps, occupy about 30% of the total wasp species, and contain both social and non-social wasp species. These wasps are classified as stinging wasps as their ovipositor has been modified, over time, into a defensive tool, that we now call, the stinger. This is also why only female wasps have stingers, as only female wasps have ovipositors and can lay eggs! Non-social aculeate are exactly as they sound. They live in individual nests, and fend for themselves. However, these non-social aculeate wasps also engage in parasitoid behavior, except these wasps can only lay eggs onto a host, and not into a host, as they lack the specialized ovipositor that other parasitoid wasps have. They may also provision their nests with additional hosts for their larvae, while the adults consume mostly plant nectar. These solitary wasps account for about 97% of aculeate wasps, with the remaining 3% accounting for the social wasps that most people are familiar with (i.e. paper wasps, hornets, and yellow jackets). These wasps live in colonies with a queen and a cast of workers, and can often be aggressive and territorial. Social wasps also provision their young with prechewed arthropods. Adult social wasps feed on a wide variety of arthropods, as well as nectar.
What do wasps do?
While a wasp's life sounds frightening, they provide many important services for our environment, such as pollination, decomposition, seed dispersal, and biological control.
Biological Control
Wasps hunt a wide variety of arthropods and serve as natural "pest control" and regulate populations of many pests in our ecosystem. Social wasps are generalist hunters, while parasitoid wasps are often specialized hunters and capture specific prey, such as, caterpillars, beetles, flies, spiders, and other pests. Regulating these populations is important as many arthropods can reproduce rapidly and can be harmful if left unchecked. It is predicted that this service done by aculeate wasps is likely to be equal to, or more effective than the service done by insectivorous birds, mammals and amphibians. Parasitoids often target specific life stages of pest arthropods, such as, the larval stage or pupal stage. Wasps are so successful at regulating arthropod populations that populations of parasitoids have been deployed into agricultural systems, or used in conservation efforts when there is an increase in pest, or invasive arthropods. For example, the US Department of agriculture has deployed parasitoid wasps that specialize in hunting wood-boring beetle larvae, to combat emerald ash borers throughout the US.
Wasps hunt a wide variety of arthropods and serve as natural "pest control" and regulate populations of many pests in our ecosystem. Social wasps are generalist hunters, while parasitoid wasps are often specialized hunters and capture specific prey, such as, caterpillars, beetles, flies, spiders, and other pests. Regulating these populations is important as many arthropods can reproduce rapidly and can be harmful if left unchecked. It is predicted that this service done by aculeate wasps is likely to be equal to, or more effective than the service done by insectivorous birds, mammals and amphibians. Parasitoids often target specific life stages of pest arthropods, such as, the larval stage or pupal stage. Wasps are so successful at regulating arthropod populations that populations of parasitoids have been deployed into agricultural systems, or used in conservation efforts when there is an increase in pest, or invasive arthropods. For example, the US Department of agriculture has deployed parasitoid wasps that specialize in hunting wood-boring beetle larvae, to combat emerald ash borers throughout the US.
Seed Dispersal
Social wasps have also been observed participating in insect mediated seed dispersal. Insect Mediated seed dispersal is when an insect, mainly ants, feed a fatty, protein rich part of a seed (called an eliasome) to their young, but discard the living, healthy part of the seed that may grow into a new plant. Social wasps have been shown to participate in seed dispersal where they feed their offspring part of the seed and discard the healthy part of the seed. Social wasps are believed to support 10 plant species, across 12 different wasp species. Unfortunately, it is difficult to estimate the importance of this service as wasp mediated seed dispersal is a largely unresearched field, but it is predicted to be more common than current scientific literature suggests.
Social wasps have also been observed participating in insect mediated seed dispersal. Insect Mediated seed dispersal is when an insect, mainly ants, feed a fatty, protein rich part of a seed (called an eliasome) to their young, but discard the living, healthy part of the seed that may grow into a new plant. Social wasps have been shown to participate in seed dispersal where they feed their offspring part of the seed and discard the healthy part of the seed. Social wasps are believed to support 10 plant species, across 12 different wasp species. Unfortunately, it is difficult to estimate the importance of this service as wasp mediated seed dispersal is a largely unresearched field, but it is predicted to be more common than current scientific literature suggests.
Decomposition
Social wasps have been shown to participate in the decomposition, where they scavenge from carcasses of decaying animals (mainly in the first stage of decomposition). Similar to wasp mediated seed dispersal, little research has been done on wasps' role in decomposition, so its importance is difficult to estimate.
Social wasps have been shown to participate in the decomposition, where they scavenge from carcasses of decaying animals (mainly in the first stage of decomposition). Similar to wasp mediated seed dispersal, little research has been done on wasps' role in decomposition, so its importance is difficult to estimate.
Pollination
Wasps are important pollinators. Like bees, adult wasps are high energy and require a lot of pollen and nectar for survival. However, wasps aren't covered in as much hair as bees, so they do not pick up pollen at the same rate, but they still play a key role as pollinators in our environment. There are both specialist and generalist wasp pollinators. For example, figs and many species of orchid rely solely on specialist wasps for pollination. It is estimated that around 800 plant species are pollinated by wasps. Aculeate wasps belonging to the vespid family (i.e. paper wasps, yellow jackets, etc.) dominate as generalist pollinator, as the variability between flowers is very high. Social wasps are considered the "backup" pollinators as they lack preference for specific plants, like bees have, and are important in areas with fragmented or degraded environments.
Wasps are important pollinators. Like bees, adult wasps are high energy and require a lot of pollen and nectar for survival. However, wasps aren't covered in as much hair as bees, so they do not pick up pollen at the same rate, but they still play a key role as pollinators in our environment. There are both specialist and generalist wasp pollinators. For example, figs and many species of orchid rely solely on specialist wasps for pollination. It is estimated that around 800 plant species are pollinated by wasps. Aculeate wasps belonging to the vespid family (i.e. paper wasps, yellow jackets, etc.) dominate as generalist pollinator, as the variability between flowers is very high. Social wasps are considered the "backup" pollinators as they lack preference for specific plants, like bees have, and are important in areas with fragmented or degraded environments.
Why do we hate wasps?
“Hornets and wasps… are devoid of the extraordinary features which characterize bees; this we should expect, for they have nothing divine about them as the bees have.” (Aristotle, c. 300 BC)
The truth is, our hatred of wasps is culturally ingrained. As evidenced by the quote from Aristotle, we have despised wasps for a long time. This is due to deep rooted cultural perceptions of wasps, that stems from a lack of understanding of wasps and their ecosystem services. This bias allows many to overlook the services provided by wasps, which are also vital to the success of our ecosystem. The stigma against wasps has also had an impact on a scientific level, where many researchers are dissuaded from preforming studies on social wasps.
wasps in your garden
As discussed, wasps are very important, and beneficial members of our environment, and many different wasps can be found in urban gardens! This next section will cover some wasps that may be found in your garden, as well as, what services they provide and general information about them
Social Wasps
Most people are very familiar with social wasps in their garden. Two of the most common types of social wasps are, Paper Wasps, Yellow Jackets.
Most people are very familiar with social wasps in their garden. Two of the most common types of social wasps are, Paper Wasps, Yellow Jackets.
- Paper wasps and their nests are often found around homes. These wasps build their nests out of a mixture of dead wood fibers and their saliva to make a gray or brown, paper-like material. These nests have open cells and hang from a stalk off of the surface they are attached to. Paper Wasps consume nectar, beetle larvae, flies, and caterpillars. They will also feed their young prechewed prey. Unlike Yellow Jackets and Bald Faced Hornets, Paper Wasps are not aggressive, and will only attack if they find themselves or their nest threatened.
- Yellow Jackets may live underground, or above ground. They are very aggressive predators, which makes them important for regulating insect species, but this also makes them to many people. Since they are such aggressive predators, Yellow Jackets require a lot of sugars and carbs, and enjoy eating fruits, flower nectar, and tree sap. On the other hand, Yellow jackets feed their larvae bits of chewed up insect, and meats. This is why Yellow Jackets often target sweet drinks, or try to invade your barbeque, or picnic.
- Don't exhale on a wasp! Wasps associate hot CO2 with the mouth of a predator, if you breathe out onto a wasp, they will assume you are going to eat them, like a predator would. So if a wasp is around you, and you are afraid, try to breathe away from it.
- Wasps are smart! New Paper Wasps around your property may be aggressive at first, but don't worry. New evidence shows that Paper Wasps can recognize human faces. Over time, if you're kind and respectful to the wasps, they can recognize that you are not a threat to your hive and will leave you alone. Even if the wasps are close to your door, or mail box, and there are slight disturbances and vibrations they can recognize, over time that you will not harm them.
Potter Wasps
Potter Wasps are solitary Aculeate that build their nests out of a combination of dirt and their saliva. These nests are often in the shape of their pots, which is where they get their namesake. Potter wasps build their nests on many different surfaces, and existing cavities, including, abandoned insect tunnels, abandoned solitary bee/wasp homes, old nail holes, screw shafts on electronic devices, and many other spaces. Adult Potter Wasps feed on nectar, but collect beetle larvae, spiders, and caterpillars to provision their nests with. Potter Wasps have stingers, but are often skittish and docile, and often will not sting, unless their nests are attacked.
Potter Wasps are solitary Aculeate that build their nests out of a combination of dirt and their saliva. These nests are often in the shape of their pots, which is where they get their namesake. Potter wasps build their nests on many different surfaces, and existing cavities, including, abandoned insect tunnels, abandoned solitary bee/wasp homes, old nail holes, screw shafts on electronic devices, and many other spaces. Adult Potter Wasps feed on nectar, but collect beetle larvae, spiders, and caterpillars to provision their nests with. Potter Wasps have stingers, but are often skittish and docile, and often will not sting, unless their nests are attacked.
Mud Daubers
Anywhere there may be a leaky hose or wet dirt, there will probably be a Mud Dauber. Mud Daubers are solitary Aculeate (stinging) wasps, but are very docile and keep mostly to themselves. The two Mud Daubers you are most likely to encounter in your garden, are the Yellow and Black Legged Mud Dauber (Sceliphron caementarium) and the Blue Mud Dauber (Chalybion californicum). These wasps have a distinct, "thread-like" waist, and get their name from the nests they make out of mud. These nests are tube-like and often resemble pipe organs or pan flutes when gathered together. They prefer to place their nests on vertical or horisontal, walls, bridges, or overhangs. Mud Daubers provision their nests with all sorts of spiders. Black and Yellow Mud Daubers will provision their nests with spiders like, crab spiders, orb weavers, and smaller jumping spiders, while Blue Mud Daubers are famous for provisioning their nests with Brown and Black Widows. Mud Daubers are known to return to their old nests year after year, so if you spot Mud Daubers around, you will likely have them around for a while. However, if the Mud Daubers leave, other solitary wasps and bees are likely to take up residence in the Daubers' old home.
Anywhere there may be a leaky hose or wet dirt, there will probably be a Mud Dauber. Mud Daubers are solitary Aculeate (stinging) wasps, but are very docile and keep mostly to themselves. The two Mud Daubers you are most likely to encounter in your garden, are the Yellow and Black Legged Mud Dauber (Sceliphron caementarium) and the Blue Mud Dauber (Chalybion californicum). These wasps have a distinct, "thread-like" waist, and get their name from the nests they make out of mud. These nests are tube-like and often resemble pipe organs or pan flutes when gathered together. They prefer to place their nests on vertical or horisontal, walls, bridges, or overhangs. Mud Daubers provision their nests with all sorts of spiders. Black and Yellow Mud Daubers will provision their nests with spiders like, crab spiders, orb weavers, and smaller jumping spiders, while Blue Mud Daubers are famous for provisioning their nests with Brown and Black Widows. Mud Daubers are known to return to their old nests year after year, so if you spot Mud Daubers around, you will likely have them around for a while. However, if the Mud Daubers leave, other solitary wasps and bees are likely to take up residence in the Daubers' old home.
Sand Wasps
As their name suggests, Sand Wasps burrow, and create their nests in sandy, dry dirt. These wasps are solitary, and are often black and white, or black and yellow, and have bands similar bees. These wasps provision often their nests with flies and can catch them on wing. Adults feed on nectar. Sand Wasps have stingers, but are very docile. Bembix americana (pictured right) often fly around people and catch flies that gather around them. They will also eat injured flies out of people's hands. These wasps are most common during the hottest months of summer, when fly populations are at their highest. Bicyrtes Quadrifasciatus, also known as the Four-Banded Stink Bug Hunter Wasp (pictured left) is an important predator of the marmorated stinkbug, which is an invasive stinkbug in North America.
As their name suggests, Sand Wasps burrow, and create their nests in sandy, dry dirt. These wasps are solitary, and are often black and white, or black and yellow, and have bands similar bees. These wasps provision often their nests with flies and can catch them on wing. Adults feed on nectar. Sand Wasps have stingers, but are very docile. Bembix americana (pictured right) often fly around people and catch flies that gather around them. They will also eat injured flies out of people's hands. These wasps are most common during the hottest months of summer, when fly populations are at their highest. Bicyrtes Quadrifasciatus, also known as the Four-Banded Stink Bug Hunter Wasp (pictured left) is an important predator of the marmorated stinkbug, which is an invasive stinkbug in North America.
Tiphia Wasps
These small wasps are easy to overlook, and are often misidentified as flying ants. Tiphia wasps do not have nests, and instead, lay their eggs directly onto their host. The females do this by burrowing underground and laying their eggs onto beetle larvae, especially those belonging to the scarab beetle family. This makes Tiphia Wasps important predators of scarab beetles, such as the invasive and destructive Japanese Beetle. Additionally, these wasps were native to Japan, Korea, and Northern China, and were introduced to the U.S. to regulate the Japanese Beetle population. Adult Tiphia wasps prefer to feed on honeydew produced from aphids, and plant nectar. Maple, Cherry, and Tulip trees seem to be popular locations for Tiphia Wasps.
These small wasps are easy to overlook, and are often misidentified as flying ants. Tiphia wasps do not have nests, and instead, lay their eggs directly onto their host. The females do this by burrowing underground and laying their eggs onto beetle larvae, especially those belonging to the scarab beetle family. This makes Tiphia Wasps important predators of scarab beetles, such as the invasive and destructive Japanese Beetle. Additionally, these wasps were native to Japan, Korea, and Northern China, and were introduced to the U.S. to regulate the Japanese Beetle population. Adult Tiphia wasps prefer to feed on honeydew produced from aphids, and plant nectar. Maple, Cherry, and Tulip trees seem to be popular locations for Tiphia Wasps.
Cuckoo Wasps
Also known as Emerald Wasps, these wasps have a bright green, metallic exoskeleton that is hard to miss in your garden. These solitary wasps have a unique approach to rearing young when compared to other wasps. Like the Cuckoo Bird, a female Cuckoo Wasps will lay her egg in the nest of a host family, which usually consists of another family of wasps. When the Cuckoo Wasp egg hatches, the newly emerged larvae will consume the host family's offspring and will eat the food provided for the host's offspring. The adults feed on nectar, and particularly enjoy flowers belong to the Umbelliferae family (carrots, celery, parsley, etc.) and the Compositae family (aster, daisy, composite, sunflower, etc.). Similar to pill bugs, Cuckoo Wasps also roll into a defensive curl when threatened (pictured left)
Also known as Emerald Wasps, these wasps have a bright green, metallic exoskeleton that is hard to miss in your garden. These solitary wasps have a unique approach to rearing young when compared to other wasps. Like the Cuckoo Bird, a female Cuckoo Wasps will lay her egg in the nest of a host family, which usually consists of another family of wasps. When the Cuckoo Wasp egg hatches, the newly emerged larvae will consume the host family's offspring and will eat the food provided for the host's offspring. The adults feed on nectar, and particularly enjoy flowers belong to the Umbelliferae family (carrots, celery, parsley, etc.) and the Compositae family (aster, daisy, composite, sunflower, etc.). Similar to pill bugs, Cuckoo Wasps also roll into a defensive curl when threatened (pictured left)
These were just a few examples of wasps that may visit your garden. You may have wildly different wasps that visit your garden depending on your location, and your surroundings.
If you are interested in identifying wasps in your garden, insect identification may be a useful tool to catalog the wasps in your yard.
If you are interested in keeping track of the wasps you see in your yard or in other green spaces, check out inaturalist, a website dedicating to recording and identifying observations in nature.
If you are interested in keeping track of the wasps you see in your yard or in other green spaces, check out inaturalist, a website dedicating to recording and identifying observations in nature.
About the project and author
My name is Jackson Knight and I am a biology major at Lawrence university. I have a profound love for all insects and I hope to pursue a PhD in Entomology. I created this website for the purpose of educating people of the importance of wasps. It served as a product for my senior research project. My research was an exploratory project, set out to collect data on the wasp biodiversity in the Appleton area, and create groundwork for future ecological wasp research in Wisconsin.