What critter could do this?

Asked July 29, 2018, 1:28 PM EDT

Went to get some 1/2" copper pipe out of the Rafters of my shed. I noticed a bundle of grass sticking out of it. Figured I must have jabbed it in to the ground before storing it years ago. Once down, I started to pull them out and they come out as individual blades about 3/4" to 1 1/2" long very easily, not a mass that is hard to get out if it has a plug of lawn. I realized it must be some sort of nest, as I also noticed a similar "plug" in the end of some 1/2" pvc pipe. So a nest of what? First thought was some sort of wasp but what I discovered inside does not indicate a wasp nest. About 1 inch into the pipe there where what appeared to be a chrysalis or an egg. Not just one but 4-5. Each one is about 1/2" in diameter. (Perfectly the size of inside the pipe) and about 1" - 1 1/4" long. They are papery such as a chrysalis that didn't survuve would be. It appears one had opened. I ruled out any sort of larvae as this is in the rafters of my shed and doubt any sort of caterpillar would make that trek. Also the size is huge. My only thing I could think of is a humming bird, but I am unaware of how the humming bird egg appears as it ages and all humming bird nest I have seen are constructed and the female tends to the young. There would have been no way for the mother to tend to the hatchlings and her aim would have had to be perfect to get the eggs into the pipe. I will attach photos once i figure out a good way of getting a good picture of them

Lane County Oregon beneficial insects wasps

2 Responses

My best guess, without an image is that you have the nest of a grass-carrying wasp. Most online links describe Isodontia mexicana whereas the species here in the west is Isodontia elegans.

They won't sting and don't build a large nest. They are considered beneficial because they help limit certain other insects.

The small capsules each contain an egg which will soon hatch and a stash of paralyzed snow crickets which will be the larva's (youngster's) food. The adults will emerge next summer and restart the life cycle.



Thank you so much for the very quick response.

I think you you nailed it on the head.

The size of of the “eggs” is what threw me