Everything you need to know about wasp control in California
How do you get rid of a wasp nest?
The Northwest Center for Alternatives to Pesticides recommends leaving nest removal to professionals who are “experienced in dealing with stinging insects and wearing protective clothing.” But if you need to remove a nest yourself, here are some tips.
What’s buzzing in California? It’s not bees or mosquitoes, but wasps. Wasps are active year-round, but are most noticeable from March to November. During this peak season, their colonies are at full size, leading to increased foraging behavior near food sources.
California’s warm climate allows for a long wasp season, with common species including yellowjackets, paper wasps, and hornets. Wasps are more common during these months, so it’s important to be careful around their nests and avoid potential attractants.
“This is a really big year for wasps,” Lynn Kimsey, director of the UC Davis Bohart Museum of Entomology, told the Sacramento Bee.
Here’s everything you need to know about wasps in California.
What species of wasps live in California?
California is home to a variety of wasp species. The most common species include:
- Yellow Jackets: These wasps are more aggressive and can become a nuisance, especially near food and garbage. They have stout bodies with black and yellow markings. “The concern about yellowjackets stems from their persistent, combative behavior near food sources and their aggressive defense of their colony,” wrote the University of California’s Division of Integrated Pest Management.
- Paper wasps: These wasps are often seen building umbrella-shaped nests under eaves, in attics or other sheltered areas. They have slender bodies with long legs and are usually brown with yellow or red markings. Most species are relatively non-aggressive, but they can become problematic when they nest above doorframes or in other areas of human activity, such as fruit trees, reports UCIPM.
- Clay wasps: These solitary wasps build nests out of mud, often on walls or in sheltered areas. They have long, slender bodies and are usually black or metallic blue. They do not defend their nests and rarely sting. In winter, you can safely remove the nests without spraying, reports UCIPM.
- Cicada Killer: These are large wasps that dig burrows in the ground. They are known for their size and their ability to hunt cicadas. They have reddish-black bodies with yellow markings.
- Tarantula Hawks: These are large wasps with metallic blue-black bodies and bright orange wings. They are known for their painful sting and their hunting of tarantulas.
- Velvet ants: Despite their name, velvet ants are wasps. Females are wingless and covered with thick hair, often bright red, orange or yellow.
Are California paper wasps aggressive?
California paper wasps are generally not aggressive unless they feel threatened or their nest is disturbed. These wasps are usually more defensive than offensive, meaning they only act aggressively if they believe their nest is in danger. Paper wasps may sting in defense if people approach them too closely or disturb their nest. It is important to be cautious around their nesting sites so as not to provoke them.
Are there killer wasps in California?
California is home to several species of wasps with aggressive or predatory behavior. Notable examples include the cicada killer wasp, which hunts cicadas but is generally not aggressive toward humans, and the tarantula hawk, which is known for its extremely painful sting but usually only stings when provoked.
Are wasps harmful?
Wasp stings can be dangerous due to their pain, swelling, and allergic reactions. While most stings are not life-threatening, allergic individuals can experience severe reactions that require immediate medical attention.
Due to their predatory and parasitic behavior, they are more harmful to other insects.
Why do you get stung by a wasp?
Wasps sting primarily as a defense mechanism; this reaction can be triggered by various factors. One of the most common triggers is a perceived threat to their nest.
According to ScienceDirect, an online database of scientific research, wasps release alarm pheromones when they sting or feel threatened. These pheromones can alert other wasps and trigger a coordinated defense response that results in multiple stings.
Touching or hitting a wasp can further provoke a sting, as wasps may feel threatened by direct confrontation. Vibrations near their nests caused by lawnmowers, construction equipment or loud noises can disturb wasps and lead to a defensive sting. Certain species, such as yellowjackets and hornets, are more aggressive and sting more quickly in defense of their colony than solitary wasps, which are generally less aggressive.
What should I do if I am stung by a wasp?
According to the National Institute for Occupational Safety and Health, if you are stung by a wasp, have someone check you for an allergic reaction. Wash the area with soapy water and remove the stinger with gauze or a fingernail. Do not squeeze or use tweezers on the sting site. Apply ice to reduce swelling and do not scratch the sting, as this can increase swelling, itching and the risk of infection.
How do you get rid of wasps?
To effectively eliminate wasps, use insecticides specifically designed for wasps, such as aerosol sprays with long-range nozzles. Apply the insecticide safely by following the directions on the label, preferably at dusk or at night when wasps are less active, and keep a safe distance.
Once the nest is inactive, wear protective clothing such as gloves, long-sleeved clothing and a mask and carefully remove it using a long pole or tool to avoid stings.
Smith Pest Management of San Jose recommends wasp traps as one of the most common and effective ways to get rid of wasps in your yard. The traps contain a liquid that attracts wasps. When the wasps crawl into the trap, they get stuck and drown. While wasp traps are effective, they accumulate dead wasps and can be unsightly. Replace them often and hang them away from your outdoor areas.
To prevent an infestation, seal all cracks and openings around your home, cover outdoor food and garbage, and check regularly for new nests.
Are wasps pollinators?
Yes, wasps can be pollinators, although they are less efficient than bees. According to the U.S. Forest Service, many wasps visit flowers to collect nectar, inadvertently transferring pollen and thus aiding in pollination.
Some species, such as fig wasps, have specialized pollination relationships. Although wasps have less hairy bodies than bees, which limits their pollen transport efficiency, they still contribute to pollination and support ecosystem balance. They also control pest populations and can be critical for certain plants, especially in areas with fewer bees. Overall, although wasps are not primary pollinators, they support plant reproduction and biodiversity.
Do wasps leave stings?
Unlike bees, most wasps do not leave their stinger in their victim. They have a smooth, retractable stinger that allows them to sting multiple times. When a wasp stings, it injects venom, causing pain, swelling, and possibly allergic reactions.
Schlenke explains that wasps generally only sting when they feel threatened, such as when they are roughly handled or their nest is disturbed. They usually don’t care about humans and will leave you alone unless you provoke them. If you get stung, there’s not much you can do other than wait for the itching and swelling to subside. However, removing a stinger, if present, and applying aloe vera can help.
What do wasps eat?
Wasps have different diets depending on their species and life stage. Adult wasps feed on nectar and sugary fruits for energy, especially in late summer and autumn.
They also eat other sweet substances. The larvae of social wasps require protein, which the adult wasps obtain by hunting insects and spiders and sometimes by feeding on pollen. Solitary wasps such as mud wasps and cicada killers hunt specific prey such as spiders or cicadas to lay down supplies for their larvae. Social wasps also forage for carrion and seek out protein-rich foods and are more visible near human food sources in late summer and fall.
What is the difference between wasps and yellowjackets?
Yellowjackets are a specific type of social wasp known for their black and yellow stripes and aggressive behavior, especially near their nests and sugary foods. They are often a nuisance at outdoor events. In contrast, “wasp” is a broader term that includes various species, such as paper wasps and hornets, that vary in appearance and behavior. Although all yellowjackets are wasps, not all wasps are yellowjackets.
What is the difference between a wasp and a hornet?
Hornets are a type of wasp that are generally larger, hardier, and more aggressive, especially when defending their nests. They often have a mix of black, yellow, and orange colors and build larger nests compared to other wasps. In contrast, the term “wasp” encompasses several different species, such as paper wasps and yellowjackets, which vary in size, color, and behavior.
