Western Yellowjacket

Macro field-guide photograph of a yellowjacket wasp

Western Yellowjacket

Vespa · Health risk

Peak aggression arrives in late August, not July.

How to identify

  • Bright yellow and black bands, 1/2 inch
  • Smooth body, tucked legs in flight
  • Nests in ground cavities, soffits and wall voids

Signs of activity

  • Steady traffic into one hole
  • Papery nest in an eave
  • Aggressive interest in food and drinks outdoors

When they’re active

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Three Most Common Types of Wasps in Colorado

Here in Colorado,  the three most common types of wasps are the western yellow jacket, the western paper wasp, and the baldfaced hornet. Continue scrolling to learn more about these stinging insects. 

Why Wasps Get More Aggressive in Late Summer (And What You Can Do About It)
A Comprehensive Guide To Common Wasps & Yellow Jackets In Colorado

Western Yellow Jackets

When trying to identify western yellow jackets, look for hairless stinging insects that have black and yellow or black and white markings and very small waists.

Yellow jackets tend to be ground-nesters and so you’ll often find yellow jacket nests in ground holes, around railroad ties, and under buildings.

Paper Wasps

In Colorado, both western and eastern paper wasps are plentiful and are similar in appearance to yellow jackets but are mostly brown with some yellow. The bands of coloring on their bodies varies by species but may include bolder colors. 

Where paper wasps nest also varies by the species with western paper wasps preferring overhangs, trees, and other suspended, sheltered areas. 

Eastern paper wasps, on the other hand, often build their nests inside small cavities on buildings, inside pipes and gutters, and in manmade items such as grills. 

Types Of Wasps In Colorado
Types Of Wasps In Colorado

Baldfaced Hornets

Not a hornet at all, baldfaced hornets are wasps that easily distinguished by the mostly black bodies and white-patterned faces. 

Baldfaced hornets tend to build their large nests under overhangs, on eaves, in trees, and inside bushes.

Frequently Asked Questions

Colorado Wasps FAQs

Stinging insects such as wasps and yellow jackets send over 500,000 people to the emergency room each year. With this in mind, it’s clear to see that yellow jackets pose significant health threats to humans as they may sting repeatedly and can cause allergic reactions.
No real reason. Most homes in our area experience wasps and yellow jackets around their house primarily during the summer months.
Getting rid of wasps and yellow jackets can be a dangerous task. That’s why our service includes everything necessary for one fee. Our treatment method consist of the following:
  • Detailed inspection of the entire structure to identify areas of activity and entry points.
  • Active nests will be treated and removed if accessible.
  • A preventative treatment will be applied in the area of the nests, as well as common areas where they may re-build. A yellow jacket trap may be installed to help capture foragers.
This is a one-time service. For greater protection and money savings learn about Colorado’s Choice home pest control program or Colorado’s Select for businesses.
EnviroPest uses the least amount of material as possible while still resolving the problem. We utilize natural products, baits, and mechanical means as a form of treatment as much as possible. When conventional materials are required, we follow very stringent guidelines for the use of the product so that it poses no threat to people or pets. All products are registered by the EPA. Our service technicians will inform you of any specific safety measures that need to be taken.
We take all pest problems seriously and are committed to helping you ASAP. In most cases, we can respond the same or very next day.
Treatment cost for yellow jackets and other wasps varies, however you can visit our Colorado’s Choice program page for more information or request a quote here!
It’s virtually impossible to prevent yellow jackets, wasps, and other stinging insects from showing up on your property but you can make your property less appealing to them. We recommend these tips:
  • Avoid wearing strong smelling perfumes and colognes when you’re likely to be outside.
  • Wear light-colored clothing.
  • Don’t let outdoor trash cans get to the point where they’re overflowing and always make sure they are covered.
  • Cover food and drinks when you’re eating outside.
  • Fill in holes in the ground.
  • Seal any openings that wasps might use to enter your home.
  • Sign up for ongoing pest protection so you don’t have to worry about bugs all year-long!

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Eric G.

Eric G.

Great experience with the pest control service. Alexander did a thorough job spraying both the inside and outside of the home and took the time to explain what they were doing. I especially appreciated that he didn’t just treat the home but also pointed out areas around the house that could allow pests to get inside and recommended repairs and preventative measures to help keep them out. The service was professional, thorough, and informative, and I appreciated the attention to detail. I would definitely recommend them to anyone looking for reliable pest control and helpful advice from Alexander on preventing future pest problems.

Eric G.
a month ago

Aaron S.

Aaron S.

Our garage had been infested with mice. They left quite a mess. EnviroPest has systematically worked to eradicated the mice, mitigate entry points, and most recently completed a thorough cleanup and sanitation process. Along the way, they have all been professional, friendly, and have gone out of their way to explain their findings and recommendations. I never felt like we were being upsold. Overall very satisfied and would call them again if needed.

Aaron S.
3 months ago

A V.

A V.

Mark has come to service my property a few times and does a great job answering questions and focus on my areas of concern. I like having the rapport with someone familiar with my previous service and property needs.

A V.
6 months ago

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