Weird Insect Nests - Ask Extension
Hi!
A new insect find our house this year. We often have our casement windows open on beautiful September days. Some industrious insects decided to b...
Knowledgebase
Weird Insect Nests #890136
Asked November 21, 2024, 2:17 PM EST
Hi!
A new insect find our house this year. We often have our casement windows open on beautiful September days. Some industrious insects decided to build nests on the tops of the open windows!
I saw the insect itself only once. It looked bee-like. It flew to the top of the window carrying a single blade of dead grass, which it added to the little pile.
Once the little of bundles of grass were to their liking, they proceeded to deposit small green larvae inside.
We have never seen or heard of such a thing!
Does this description sound familiar? We'd love to know what to call our little visitors!
Thank you!
Benton County Oregon
Expert Response
Hello,
Wow that does sound fascinating! Are you able to upload a photo or two of the insect nests and larvae (if not the insect itself)? This will help our experts with their identification.
Thank you!
Hi Anna,
I was too busy thinking “Ewww! Get it off!” to think to take any photos!
Of course I realize now that photos would make identifying the little guys much easier!
I was hoping their bizarre behavior might be enough. The grass blades were held vertically, and were probably ten times the height of the bug carrying them. It was amazing! They reminded me of when a helicopter lifts a log from a hard to access location.
Perhaps they are common and well-known to others, I just didn’t get the memo!
Marion
On Nov 21, 2024, at 1:10 PM, Ask Extension wrote:
Hi Marion,
Wow, this insect sounds even more strange and fascinating! I will share your details with one of our insect experts (and will stay tuned myself to learn more).
Thanks again!
Based on your description I am going to guess you saw Isodontia elegans, the elegant grass carrying wasp. They use grass in the construction of their nests which they provision with paralyzed prey. However, the prey are typically katydids and tree crickets and you saw "larvae", which could have been the wasp brood or an a-typical prey item.
See if these photos match what you saw:
See: https://bugguide.net/node/view/23933
Here is a article about them from a study in Hillsboro, OR. You can see a photo of the nest:
https://bioone.org/journals/western-north-american-naturalist/volume-81/issue-4/064.081.0408/Nesting-Biology-and-Offspring-Development-of-the-Cavity-Nesting-Solitary/10.3398/064.081.0408.pdf
See if these photos match what you saw:
See: https://bugguide.net/node/view/23933
Here is a article about them from a study in Hillsboro, OR. You can see a photo of the nest:
https://bioone.org/journals/western-north-american-naturalist/volume-81/issue-4/064.081.0408/Nesting-Biology-and-Offspring-Development-of-the-Cavity-Nesting-Solitary/10.3398/064.081.0408.pdf
THANK YOU!!!
This is certainly an excellent theory, based on the minimal information I provided.
I was not able to access the photos on the link, but using the insect’s name I was able to look some up.
We never saw the hive-like nests in the grass bundles, but we could have missed them.
It is amazing that it took these guys thirty years to decide our house was the place to set up camp. I have never seen or even heard of them before! Ah, the mysteries of nature!
Thanks again for your help!
Marion
On Nov 26, 2024, at 9:31 AM, Ask Extension wrote:
