By the Numbers: Inside Washington’s Murder Hornet Nest

After the Washington State Department of Agriculture (WSDA) found and removed an Asian Giant Hornet nest late last month, there was still one major step left; opening and examining the nest.

Removal of the nest itself was complicated due to the fact that it was tucked inside a tree. Once WSDA entomologists had safely removed the hornets living in the nest, they also removed the tree itself before splitting it open to reveal the nest inside.

The nest was just over 8 feet high in the tree and, once opened, was found to be about 14 inches long and 9 inches wide. So far, over 500 Asian Giant Hornet specimens in various stages of development have been collected from the nest, and the counting is still ongoing! 

Here are the preliminary results of what WSDA entomologists found in the nest.

  • 6 combs – There were six layers of comb in the nest. Combs are the structures that hold the hornet larvae as they develop. Part of the interior of the tree had been chewed away to accommodate the combs.
  • 776* cells – The combs are made up of cells and each individual cell can hold a developing Asian giant hornet. *This number is approximate as there was some damage to the combs.
  • 6 unhatched eggs These eggs were all located in the last and smallest of the combs.
  • 190 total larvae - The larvae are whitish “grubs” in uncapped cells. Many had fallen out of the combs into the tree cavity during the nest removal.
  • 108 capped cells with pupae – Pupae are the next stage after larvae. Based on the size of the cells, most of the pupae found are believed to be pupae of new virgin queens.
  • 112 workers – This total includes 85 workers that were vacuumed out of the nest on Oct. 24. All of the workers survived being vacuumed out of the nest.
  • 9 drones – Drones are male hornets and they generally emerge from the nest before the new queens emerge.
  • 76 queens – Most likely all but one queen would be new virgin queens. New queens emerge from the nest, mate, and then leave to find a place to overwinter and start a new colony the next year.

Despite multiple applications of carbon dioxide, removal of the workers, and storage in a cold facility, most of the specimens were still alive when the nest was opened.

Nest reassembled in tree - image from WSDA blog

WSDA’s Future Plans

WSDA plans to continue trapping through at least Thanksgiving and possibly beyond, but will likely only track worker hornets. Even if no other hornets are found, WSDA will continue to trap for at least three more years to demonstrate the area is free from Asian giant hornets.

If you may have seen an Asian giant hornet in Washington State, report it with a photo if you can get one at:

If you believe you have seen an Asian giant hornet but live in another area, please report it to your state or province’s invasive species managers.

Source: WSDA website

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Learn the Difference Between the Asian Giant Hornets and this Texas Native Species

This month, many Texas residents mistakenly believed they encountered the Asian giant “murder” hornet. In order to stave off any future bee-related backyard BBQ freakouts, researchers at Texas A&M ArgiLife have released important details regarding these recent “murder hornet” sightings.

David Ragsdale, Ph.D., chief scientific officer and associate director of Texas A&M AgriLife research said his department has received up to 10 photos of various wasps per day from people who think they’re seeing the Asian giant hornet. But what they’re actually looking at is the Texas native cicada killer wasp, or ground hornet. Many pest management agents and specialists around the state have also received “murder hornet” related inquiries.

“Most everyone has seen the cicada killer wasp, that is very large, but has mostly been ignored in the past,” Ragsdale said. “With the most recent news of the Asian giant hornet, they are now paying attention to the native Texas insect.”

Asian giant hornet and cicada killer wasp

How to Tell the Difference

Since the cicada killer wasp and their other native Texan lookalikes are currently going through a case of mistaken identity, below are key differences between them and the Asian giant hornet.

Note: Holly Davis, Ph.D., a Texas A&M AgriLife extension service entomologist in Weslaco said it’s important to know that there have been no confirmed reports of Asian giant hornets in any other U.S. location other than the northwestern corner of Washington state.

Asian Giant Hornet

  • Is 1.5 - 2 inches long
  • Its head is as wide or wider than its shoulders
  • It’s body is a combination of bright orange/yellow and dark brown
  • It has a pinched waist with brown and orange stripes that cover the abdomen

Cicada Killer Wasps

  • All three species are between 1 - 1.5 inches long
  • Their heads are narrower than their thorax
  • Their heads and thorax are typically the same dark orange or brown color
  • They also have a pinched waist, but their abdomen stripes are jagged

Asian giant hornet and Texas native species comparison

Davis says Asian giant hornets are very protective of their nests and will sting people who they view as a threat - but cicada killer wasps are mostly solitary and usually don’t attack in great numbers. Although you likely won’t deal with any Asian giant hornets in upcoming service calls, just helping your customers understand the difference between these species can save their sanity.


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