There are many different types of wasps in California. If you live in California, chances are you’ve encountered the occasional wasp buzzing around your home or backyard.
Although wasps can be a nuisance, they are also important ecosystem members, performing essential pollination and pest control services.
In this blog post, we’ll be taking a closer look at some of California’s most common types of wasps.
We’ll also provide tips on reducing the number of wasps in your area. Read on to learn more about the types of wasps in California.
1. Braconid Wasp
The Braconid Wasp is a species of parasitic type of wasps in California.
These wasps are small, around 3 to 5 millimeters long, and can range from black and white to yellow.
They typically have long, slender abdomens with a wide range of markings, from stripes to spots.
The Braconid Wasp is an important predator of several agricultural pests, including aphids and other small insect larvae.
They typically live in wooded areas and gardens, often near wood piles or areas with rotting wood.
They use their long abdomens to lay eggs inside the larvae of other insects, such as caterpillars, where they feed on them until adulthood.
As beneficial predators, Braconid Wasps help keep populations of agricultural pests down and can be a valuable asset in organic farming operations.
2. Boll’s Potter Wasp
The Boll’s Potter Wasp is one of California’s most common wasps.
It is a solitary wasp that builds small, egg-shaped clay nests on branches and plants.
They are generally brown and yellow, measuring around 0.7-1 inches long.
The females build these nests by collecting wet clay, forming it into an egg shape, and drying it in the sun.
Once the nest is completed, they fill it with caterpillars, which will be the food for their larvae when they hatch. Though they can sting if disturbed, they pose little threat to humans.
3. Pumpkin Gall Wasp
The Pumpkin Gall Wasp (Diplolepis bicolor) is a type of wasp found in California.
This small, black, and orange wasp measures approximately 5 mm in length and has a 7-11mm wingspan.
It can be identified by its distinctively shaped abdomen, which resembles a small pumpkin.
Of the different types of wasps in California, the female wasp creates galls on oak trees, where the larvae develop.
These galls appear as circular, yellow-brown patches which can remain on the trees throughout the year.
Pumpkin Gall Wasps feed on nectar and plant material, so they are an important pollinator in California’s ecosystems.
4. Common Paper Wasp
The Common Paper Wasp is one of California’s most common types of wasps.
These wasps can be found throughout the state, and they are easily recognizable due to their black and yellow striped pattern and the paper nest they create.
They are social insects and live in colonies with one queen and her female workers. The colony can range from a few dozen individuals to several hundred.
These wasps feed on other insects and can also be beneficial garden predators.
They are relatively harmless to humans but will sting if disturbed or threatened. Therefore, it is best to leave these wasps alone.
5. Common Thread-Waisted Wasp
The Common Thread-waisted Wasp is a type of wasp found throughout California.
They are relatively large insects and have black and yellow bodies. The main identifying features are their thread-like waists and long legs.
These types of wasps in California typically nest in bare ground and feed on nectar from flowers. They may also prey on other insects, like caterpillars and beetles.
Thread-waisted Wasps are usually solitary and do not form large colonies like other species.
These wasps play an important role in controlling insect populations in the wild. They are also beneficial for pollination since they feed on nectar from flowers.
Despite their intimidating appearance, these wasps are generally not aggressive and will not attack humans unless provoked.
Therefore, it is important to be mindful of their presence if found near your home or in the wild.
6. Cuckoo Wasp
Cuckoo Wasps are a unique type of wasp found in California.
These small wasps have slender bodies and long legs and come in various colors ranging from yellow to orange to black.
They feed on other insects and often prey on caterpillars and spiders.
Cuckoo Wasps, one of the types of wasps in California, typically nest in trees, though some will also build their nests under stones or logs.
They are very common in California, especially during the warmer months of summer.
These wasps can be beneficial in some situations, as they are known to reduce pest populations.
However, they can also be a nuisance if they nest near humans or livestock.
If you find a cuckoo wasp nest near your home, removing it or contacting an exterminator for assistance is best.
It is also important to take preventative measures to discourage them from returning. This can include removing nearby food sources and keeping your yard well-maintained.
7. European Paper Wasp
The European Paper Wasp (Polistes dominula) is a species of wasp native to Europe and parts of Asia but has also been introduced to California.
It has a black head, thorax, and abdomen, with yellow stripes on its abdomen. It is a solitary wasp, meaning it does not live in colonies.
The European Paper Wasp builds its nests from chewed wood pulp mixed with saliva and then attached to plants or structures near their preferred food sources.
The European Paper Wasp can be found around buildings, wood piles, and even abandoned cars in California.
They tend to stay away from human activity, so they can often be found in places with less foot traffic.
These wasps eat nectar and small insects like caterpillars and fly larvae. When disturbed, they will sting, so it’s important to keep a safe distance if you come across one.
However, these types of wasps in California are beneficial since they can help control insect pests.
8. Four-Toothed Mason Wasp
The four-toothed Mason Wasp (Monobia quadridens) is a species of wasp found in California.
This wasp species builds mud cells on trees and walls, often utilizing previously constructed nests. They will also create nests in abandoned snail shells and beetle larvae.
Unlike some other species, this wasp has no queen; each female acts as a queen and is responsible for their own nest.
The four-toothed Mason Wasp has a shiny black and yellow striped abdomen ranging from 10-20 mm long.
Like other types of wasps in California, they feed on nectar and small insects.
Despite the potential to cause harm, these wasps are beneficial predators that help keep other insect populations in check.
9. Giant Ichneumon Wasp
Giant Ichneumon wasps (Megarhyssa spp) are one of the most intimidating species of wasps found in California.
As their name implies, they are quite large, measuring up to two inches in length with a wingspan of four inches.
These wasps are usually black and yellow with long and slender bodies.
Of the several types of wasps in California, they tend to live in wooded areas or piles and often dig deep into the wood for their nests.
When disturbed or threatened, these wasps are not aggressive and will not sting unless handled roughly.
However, they should be treated with respect due to their large size.
10. Great Black Wasp
The Great Black Wasp is a more common species of wasp found in California.
This large, black, and yellow wasp can reach up to 1.25 inches long and is known for its boldness and aggressive behavior.
It can often be seen hovering around its nests or near potential prey sources like crickets or grasshoppers.
The Great Black Wasp is a solitary wasp that feeds on other insects and their larvae, making it an important predator in the food chain.
The Great Black Wasp is known for its complex nest-building behaviors and large brood cells.
Nests are typically constructed in sheltered locations, such as hollow logs, stumps, or wall cavities.
A single female will construct multiple nests with multiple brood cells that she will then populate with paralyzed prey items for her young.
Once the eggs hatch, the larvae feed on these prey items until fully grown.
The Great Black Wasp, one of the types of wasps in California, plays an important role in controlling the insect population.
11. Great Golden Digger Wasp
The Great Golden Digger Wasp is a species of solitary wasp found throughout California. These wasps have long, dark-colored wings with yellow or white markings.
They are typically seen flying around in gardens and fields. The Great Golden Digger Wasp builds its nests in dry soils and digs caves for them.
They feed on insects, spiders, and caterpillars and play an important role in controlling pest populations.
This species is large, up to 5 cm long, and can be recognized by its golden-yellow coloring.
12. Horntail Wasp
The Horntail Wasp is one of California’s most common types of wasps. It is a solitary wasp, meaning it does not form large colonies like other species.
The adult wasps are black and yellow, with long antennae and a pointed abdomen.
Moving on, they feed on various plants, including oak and pine trees, and are active during the day. They are also able to sting if threatened.
The larvae feed on decaying wood, and the adults use the galleries they create in their tunnels as nests.
13. Ichneumon Wasp
The Mesostenus thoracicus, or Ichneumon wasp, is a parasitic wasp native to California. They are about 2-3 centimeters long, with a dark brown body and white wings.
This type of wasp is an important predator of other insects, helping to keep their population numbers in check.
The Ichneumon wasp lays its eggs inside the bodies of other insects, such as caterpillars, where they hatch and consume the host insect from within.
This makes them an effective biological control agent for agricultural pests. This is also on our list of the various types of wasps you should know about in California!
The Ichneumon wasp is a pollinator of some wildflowers in California, so it’s important to remember that this species benefits our environment and should be protected when possible.
As a result of its unique habits, the Ichneumon wasp is an important part of California’s biodiversity and ecosystem.
14. Leucospid Wasp
The Leucospid wasp is found throughout much of California and is a part of the family Leucospidae.
It is one of the larger types of wasps in California, with lengths ranging from 1 to 2 inches.
The most common color for these wasps is black, but they can also be found in various shades of yellow or red.
These wasps have oval-shaped heads with narrow bodies and four wings. They feed on small insects such as caterpillars, flies, and honeydew from aphids.
Leucospid wasps are important predators of insect pests and provide a valuable service to California’s natural ecosystems.
These wasps are not considered aggressive toward humans; however, they may become disturbed when threatened.
If they become agitated, they may sting, which can be painful. However, it is best to leave them alone and not attempt to touch them.
If a leucospid wasp appears in your home or garden, observing it from a distance and waiting for it to leave alone is best.
15. Mutillid Wasp
The Mutillid Wasp, also known as the Velvet Ant, is a member of the subfamily Mutillidae.
This wasp species can be found in California and is easily identified by its black or brown body covered in fine hairs, giving it an almost velvet-like texture.
The females of this species are wingless, while the males possess short wings.
Mutillid Wasps are solitary insects that feed on larvae of other insects and other small invertebrates.
They typically construct their nests underground, often near ant mounds, and lay their eggs there.
The larvae feed on the stored provisions until they are ready to pupate into adult wasps. These species of wasps are not aggressive and rarely sting humans.
16. Noble Scoliid Wasp
The Noble Scoliid Wasp is a species of digger wasp native to California and the surrounding areas.
These wasps are easily recognized by their shiny black bodies, yellow stripes on their heads, and wings with a blue sheen.
They build underground tunnels, laying eggs and hatching them into larvae.
Once hatched, the larvae feed on other insects and pupate in their tunnels before emerging as adult wasps.
Noble Scoliid Wasps are not aggressive and will not bother humans unless provoked.
These types of wasps in California benefit the environment due to their predatory nature, as they help keep insect populations in check.
Further, they also pollinate flowers and provide important nutrients for plants, further increasing their value in a healthy ecosystem.
As such, avoiding disturbing these wasps when encountered in the wild is important.
17. Norton’s Giant Ichneumon Wasp
Norton’s Giant Ichneumon Wasp is a type of parasitic wasp that is native to California. These wasps are often black and have yellow stripes.
They measure up to two inches and are most easily identified by their long, curved ovipositors.
Compared to other types of wasps in California, their primary hosts are wood-boring beetles.
These wasps will lay their eggs inside the host’s body, and when the larvae hatch, they feed on the beetle from the inside out.
These wasps are considered beneficial to the environment as they help control pest populations.
These wasps can often nest in hollow trees, under stones, and houses. They prefer dark, moist places and will often hunt during the night.
They have also been known to take advantage of artificial lights to feed on other insects attracted to them.
If you find one of these wasps inside your home, it is best to leave them alone as they are harmless to humans.
18. Paper Wasp
Paper wasps are social wasps found in many parts of the United States, including California.
These wasps build nests that can be identified by the distinctive paper-like material that makes up their cells.
Paper wasps get their name from the papery material they use to construct their nests, typically attached to an overhead structure like a tree branch or porch ceiling.
Paper wasps are usually black and yellow or brown and yellow and can grow up to 1 inch long.
These wasps feed mainly on nectar and aphids but occasionally scavenge for food.
They can become aggressive if disturbed but are not particularly dangerous, and their stings are generally considered mild.
It is important to note that female paper wasps can sting multiple times, so it is best to leave them alone if possible.
To reduce the risk of a potential nest being built near your home, clean up any overhanging fruit or sugary liquids that might attract these creatures.
19. Potter Wasp
Potter wasps are solitary in California and other parts of the United States.
These wasps belong to the family Euodyneridae and can be identified by their small size, black and yellow stripes, and long antennae.
Potter wasps build their nests in protected areas, such as cracks in trees or walls, and use mud to make them.
These wasps are considered beneficial insects, as they are known to prey upon many pest insects, such as aphids and caterpillars.
They can also act as pollinators, making them an important part of the local ecosystem.
While these wasps possess stingers, they are generally not aggressive and rarely sting unless threatened.
As such, they are usually not seen as a threat to humans and can even be beneficial to have around.
20. Sand Wasp
If you are searching for several types of wasps in California, then Sand Wasps are one.
These wasps are commonly found near sandy and arid habitats, such as deserts, using sand to build their nests.
They typically create their nests by tunneling several centimeters into the ground and then filling the cavity with dry sand or soil.
Sand Wasps feed on nectar and other small insects and are generally beneficial for controlling pest populations.
They can range in size from 1-2 cm and have black and yellow stripes along their body, giving them a distinct appearance.
Sand Wasps are predators that can help to keep insect populations in check. They mainly feed on other flying insects, including moths, flies, and beetles.
They also play an important role in pollinating flowers, as they feed on the nectar of flowers.
Although they are considered beneficial wasps, taking precautions when dealing with them is still important, as they can sting if provoked.
Sand Wasps can be a great natural solution to control pests on your property.
21. Short-Tailed Ichneumon Wasp
Short-tailed Ichneumon Wasp, or Ophion spp., is a parasitic wasp native to California and found in areas like the Sierra Nevada, Mojave Desert, and Central Valley.
This species is small, usually about 6 to 8 mm long, characterized by its long antennae and short tail.
These wasps are reddish-brown and can be found feeding on plant nectar. They also parasitize the larvae of other insects, such as caterpillars.
The Short-tailed Ichneumon Wasp plays an important role in controlling populations of pests in California’s ecosystems. They help to keep these pest populations in check, allowing beneficial insects to thrive.
Additionally, they can act as biological controls for garden pests, reducing the number of pesticides used.
It is important to note that while they can be beneficial, they can also be dangerous if they sting humans or pets.
As such, it is best to avoid these particular types of wasps in California if possible.
22. Spider Wasp
Spider Wasps, called Entypus, are solitary, predatory wasps found throughout California. They are typically black and yellow and can grow up to 1 inch long.
These wasps are important predators in California, hunting and killing other insects such as spiders and caterpillars.
Spider Wasps, numerous in California, are known to feed on nectar and pollen from plants.
Spider Wasps build their nests by digging a small burrow in the ground.
This burrow is then filled with multiple cells that contain eggs and prey items for the wasp’s young.
The females will typically lay around 6 to 10 eggs at a time, hatching into larvae that feed on the prey item provided by their mother.
Spider Wasps rarely sting humans but can become aggressive if threatened or disturbed.
Therefore, it is best to observe them from a distance and not disturb their nests.
23. Squarehead Wasp
The squarehead wasp is a member of the Ectemnius genus and can be found in California.
These wasps are black with yellow markings, and the females have elongated heads with red eyes.
They measure 1-2 inches in length, depending on the species.
Their diet consists mostly of nectar and pollen, and they are considered beneficial insects as they feed on other insect pests.
Squarehead wasps build nests in trees, laying eggs that hatch into larvae. As adults, they are excellent pollinators and can be seen visiting flowers in search of nectar.
They also have a defensive mechanism that allows them to spray formic acid at predators if they feel threatened.
Squarehead wasps are often confused with hornets, but they are quite different.
They lack the thick stripes of a hornet, instead displaying a solid color pattern with some yellow markings.
Also, these wasps don’t build large nests as hornets; instead, they prefer to nest in small crevices or cavities in trees or walls.
Squarehead wasps can benefit gardens and crops by feeding pest insects such as caterpillars, aphids, and scale insects.
Although they rarely sting, they may be aggressive if disturbed. Observing them from a distance is best to avoid any potential danger.
24. Thread-Waisted Wasp
Thread-waisted wasps, also known as Ammophila spp., are an important type of wasp found in California.
They are most commonly found nesting in the ground, grass, and sometimes even trees.
Thread-waisted wasps are solitary, meaning they live independently and not in colonies.
Their black and yellow bands have a unique appearance, which helps them stand out from other species of wasps.
Thread-waisted wasps can range from a quarter of an inch to two inches long, depending on the species.
These wasps build nests made of mud and saliva and can often be found hovering around their nests, searching for food.
The main food source for these wasps is other insects, such as spiders, moths, and flies.
Thread-waisted wasps are beneficial to have around as they help to keep the insect population in check, reducing the number of unwanted pests in your garden or home. We aren’t done with this list of the different types of wasps in California!
25. Weevil Wasp
Weevil wasps are found in many areas of California and are commonly seen in gardens and lawns.
They are part of the Cerceris family of parasitic wasps, and their bodies have a long, slender shape with narrow antennae, long legs, and wings.
Weevil wasps are easily identified by their reddish-brown color and white markings on their wings and thorax.
These wasps feed on larvae and pupae of weevils, which they locate by digging in the soil and searching for the food source.
They are important to the natural environment because they help control weevil populations.
Weevil wasps, one of the types of wasps in California, benefit humans in many ways. Not only do they help to keep weevil populations under control, but they also act as pollinators.
This is because they feed on flower nectar while they search for weevil larvae.
They help to pollinate flowers and vegetables, aiding in the growth of crops in the garden and on farms.
Weevil wasps also provide pest control services when their larvae feed on insect larvae and other pests.
This means fewer chemicals must be used to keep pests away from plants, making them a great natural way to keep gardens and farms healthy.
26. California Gall Wasp
The California Gall Wasp (Andricus quercuscalifornicus) is a species of wasp that produces oak gall, a type of plant tissue growth, on California Valley Oak and Oregon White Oak trees.
The female wasp injects her egg into a bud on the tree, which hatches and feeds on the oak’s cells. In response, the tree forms a protective gall around the wasp larva.
The larva feeds on the gall and pupates within it as it develops. Adults emerge in late spring, mate, and lay eggs in the same tree or others nearby.
The cycle then starts anew. In addition to providing food for the wasps, oak galls provide valuable nutrients to their host trees.
27. Western Yellowjackets
Western Yellowjackets are also one of California’s most common types of wasps. They have yellow and black bands, and their colonies can reach up to 5,000 members.
These wasps feed on other insects and are particularly attracted to sugary foods such as honeydew and ripe fruits.
While Western Yellowjackets have a painful sting, they are mostly harmless and can be beneficial in controlling other pest populations.
They build their nests underground or in wall voids and return to the same nesting sites yearly.
If you suspect you have a nest of Western Yellowjackets, it is best to contact a professional pest control service to assess the situation and determine the best way to remove the nest.
While it is possible to remove the nest yourself, it is important to remember that wasps can become aggressive when their nest is disturbed.
So, it is important to use caution and follow safety protocols when dealing with them.
It is also important to avoid wearing brightly colored clothing or perfumes when working near the nest, as this can attract the wasps.
28. Yellow-Legged Mud-Dauber Wasp
The yellow-legged mud-dauber wasp (Sceliphron caementarium) is a solitary wasp found in many parts of California.
These wasps are typically black with yellow legs and about half an inch long. They build small nests made of mud on walls, tree trunks, and other surfaces.
The female wasps use their mandibles to chew up mud and then form it into small cells, which they fill with paralyzed spiders or caterpillars.
The eggs are laid on top of the prey, and the larvae feed on them until they mature.
Adult yellow-legged mud-dauber wasps feed on nectar from flowers. They also provide a valuable pest control service as they prey on potentially destructive spiders and caterpillars.
29. Red Cone Gall Wasp
The red cone gall wasp (Andricus quercuscalifornicus) is native to California. It is a small, black wasp with a red-orange tip on its abdomen.
This species of wasp can be found in areas with oak trees and is known for its unique galls on the leaves and twigs of oak trees.
These galls are round, cone-shaped structures from plant tissue formed by the wasps’ larvae.
Adult female red cone gall wasps lay their eggs inside these galls, feeding on the tissue until they emerge as adult wasps.
The presence of these galls can be detrimental to the health of an oak tree and can reduce its aesthetic value.
Fortunately, the effects of this wasp species can be managed through insecticides or natural predators such as lady beetles.
That’s not all on this list of the types of wasps in California! Keep reading!
30. Crystalline Gall Wasp
Gall flies, also called gall wasps (Andricus Crystallinus), are members of the Cynipidae family.
On trees, they produce galls that feed the wasp larva as it develops. These wasps are tiny, typically measuring no more than 8mm in length.
In scrub oak and chaparral, the crystalline gall wasp produces pine cone calls with white hairs.
The unisex generation galls are visible on the underside of brush leaves and oaks in the summer and fall.
On a leaf, the galls appear as a single, hairy clump in clubs. The smaller, more solitary bisexual generation galls can be noticed in the spring.
31. Guinea Paper Wasp
The Guinea Paper Wasp is one of California’s most common wasps. This species belongs to the family Vespidae and is native to the region.
They are distinguished by their black and yellow stripes, yellow legs, and relatively large size.
The Guinea Paper Wasp constructs its nests from chewed wood fibers and saliva, forming a papery shell to protect their colony.
These wasps are solitary and territorial but will not usually sting unless provoked.
They are beneficial predators that feed on many common garden pests, including caterpillars and aphids.
32. Spined Turban Gall Wasp
The Spined Turban Gall Wasp is a small, brown, yellow wasp native to California. It is also known as the Gall-inducing wasp due to its ability to induce galls in plants.
These galls, which appear as bumps or swellings on plant stems or leaves, result from eggs laid by the female wasp.
The galls are created to protect the eggs and larvae as they develop. Adults can be seen flying between late spring and fall, usually hovering around flowers in search of nectar or small insects as food.
While these types of wasps in California do not generally threaten humans, they should be treated cautiously, as they can sting if provoked.
33. Live Oak Apple Gall Wasp
We are still on our list of types of wasps in California, and the Live Oak Apple Gall Wasp is a small species of them.
These wasps have a reddish-brown body and a slender abdomen and can typically be found in oak trees.
They feed on the sap and leaves of these trees, which results in the formation of galls, or small round structures, on the twigs of the trees.
In addition to feeding on oak trees, they also occasionally prey on other insects. The presence of these wasps helps maintain the health of oak trees in California, as they help control the population of harmful insects.
As such, it is important not to disturb any areas where these wasps may be present.
34. Beaked Twig Gall Wasp
The Beaked Twig Gall Wasp, or Andricus foecundatrix, is an unusual type of wasp in California. It’s easily identified by its small size (1/5-inch in length) and distinctive long beak.
This species creates a gall, a swelling on the twig of a California oak tree, which contains multiple generations of offspring.
Its life cycle can take two to three years to complete and is characterized by the transformation of the gall from green to brown.
Interestingly, it is the only species to create a “double gall” with two swellings at either end of the same twig.
In addition, the Beaked Twig Gall Wasp does not sting, making it relatively safe for humans. This wraps up our list of the several types of wasps in California!
