How to Get Rid of Mason Wasps Effectively and Safely

Mason wasps are fascinating creatures that can become pesky when they start building nests in unwanted areas around your home While they are not aggressive like yellowjackets or hornets, their mud nests can be an eyesore and their constant buzzing can become annoying

If you have identified mason wasps around your property you may be wondering what are the best ways to deter them without harming them. This article will provide an overview of mason wasps, explain why it’s best not to kill them and give tips for discouraging them humanely.

What Are Mason Wasps?

Mason wasps earned their name because they build nests out of mud, much like a mason uses bricks and mortar. Their genus is Eumeninae, a type of potter or mason wasp. There are over 120 species in North America alone.

These solitary wasps have a slender black and yellow or black and blue metallic body, about 5/8 to 1 inch long. They are much skinnier than yellowjackets with a thin “waist”. Males have an entirely black head and thorax while females have yellow or white markings on their faces.

Unlike social wasps like hornets, every female mason wasp builds and provisions her own nest. She does not interact with other mason wasps except to mate. The male wasps do not have stingers and only live for a few weeks to mate.

Why Mason Wasps Are Beneficial

While their mud nests may look unsightly, mason wasps are actually beneficial insects to have around. Here’s why you shouldn’t be too quick to kill them:

• They are pollinators: Adult mason wasps feed on nectar from flowers and serve as pollinators for many plant species. Their pollination is important for gardens and agriculture.

• They control pests: Female mason wasps hunt down caterpillars and other insects to provision their nests. The caterpillars are temporarily paralyzed with the wasp’s sting and placed in the nest. Then the wasp lays an egg on the caterpillar and seals it inside. When the egg hatches, the wasp larva eats the caterpillar.

• They are not aggressive: Mason wasps rarely sting unless they are directly threatened as they do not have large nests to defend. Their mild stings are comparable to a bee sting.

• They keep other insect pests in control: By hunting caterpillars and other prey, mason wasps help control populations of insects that can damage garden plants and crops.

So if possible, it’s best to just leave mason wasps alone and appreciate their presence. But if they are nesting where they are clearly unwanted, there are some effective ways to deter them without killing them.

Discouraging Mason Wasps Humanely

Here are some tips for safely discouraging mason wasps from building nests in unwanted areas around your home:

Remove and clean existing nests

• Look for nests under eaves, awnings, decks, patio furniture, or on the side of the house. Mason wasp nests are made of mud and resemble clusters of pits or tubes.

• Wear protective clothing like a bee suit or long sleeves and pants to avoid stings. Work at night when wasps are less active.

• Knock down the nests using a brush or scraper. Be sure to also scrape away any mud nest remnants stuck to the surface.

• Wash the area with soap and water to remove any pheromones that could attract other wasps.

Seal holes and crevices

• Mason wasps build nests in existing cavities and holes, so sealing cracks shuts down their nesting sites.

• Seal holes in wood, gaps around window frames, openings under roof tiles, etc using caulk, expanding foam, wood putty, or other weatherproof sealant.

• Cover vents and weep holes with fine steel mesh to block entry but allow airflow.

Use deterrents

• Hang fake wasp nests near potential nesting sites to deter mason wasps who will avoid areas near competitors.

• Apply tansy oil, eucalyptus oil, or essential oils like peppermint and lemongrass to deter wasps from building nests.

• Place bird or bat houses to encourage natural predators that eat wasps.

Knock down started nests

• Check weekly for the start of any new nests and destroy them right away before wasps inhabit them.

• Wear protective gear and work at night if active wasps are present. Knock down nests with a broom or brush.

• This regular nest removal will eventually convince them to move on and build elsewhere.

When to Call An Exterminator

If you have a large established mason wasp nest, especially high up where difficult to reach, it’s safest to call a pest management professional.

Licensed exterminators have the proper equipment and insecticides to:

• Reach tall nests using extension tools and lifts
• Apply concentrated wasp-killing dusts or sprays into the nest openings
• Ensure the nest is completely destroyed along with any wasps inside

This professional treatment may be the best option when wasp nests are in hard to access areas or if you have an allergy and want guaranteed removal.

Coexisting With Occasional Mason Wasps

Mason wasps can be considered more friend than foe when their nests are out of the way and they aren’t bothering you.

If you spot just a few flying around gathering mud or nectar, enjoy observing their fascinating behaviors:

• Watch female wasps construct nests using mud balls held together with saliva. They fly to and from a water source, rolling up the mud like cookie dough!

• Marvel at their swift and acrobatic flying skills as they search for caterpillars. They can even hover in place like tiny helicopters.

• Notice them filling their nests by stocking paralyzed caterpillars or other insects inside before laying their eggs. Each cell is sealed off with more mud.

So coexist with mason wasps when feasible. Relocate or deter nests from problematic areas, but try to maintain admiration for these important pollinators and pest controllers! With some selective management, you can safely keep mason wasps around your yard.