Bumble bees (?) in my window wells

Asked May 3, 2018, 3:42 PM EDT

There are very large (1 -1 1/2"long) yellow and black fuzzy bees, similar to the pictures of the bumble bees on your pages, living underground in our window wells. We do not want them by our house, but do not know how to remove them safely if they are important pollinators, or kill them if they aren't too important. Can you help us out? Thank you in advance, Paul and Anne Groskreutz 612-869-2200

Hennepin County Minnesota bee removal carpenter bee horticulture

4 Responses

If you reply to this message and attach sharp photos of the bees we will probably be able to identify them and let you know how to deal with them.

At this time of year bumblebee queens are all that remain of last summer's population. These queens are now seeking places to establish nests and raise another generation. If the bees in your window well are actually bumblebees, they may be queens that overwintered there. If that's the case, they will soon disperse. Bumblebees are valuable pollinators that should be protected whenever possible.

The best I can do with the photo. No activity there this morning. There was lots of activity yesterday afternoon while it was warm. Would there have been dozens of queens from one nest?

The photo lacks the detail to be sure, but from what we can see, we believe the insects are carpenter bees instead of bumblebees. Although there is a superficial resemblance, the specific appearance and habits of carpenter bees and bumblebees differ considerably.

Go here to learn about carpenter bees and how to identify them.
https://entomology.ca.uky.edu/ef611

Carpenter bees seldom sting. Although the males often buzz aggressively, they have no stinger and are harmless. Females can sting but almost never do unless they are handled. Both sexes are present at this time of year.

If you believe the insects are carpenter bees, look for their tunnels in wood nearby. Nesting tunnels may account for the bees' presence. Otherwise we can't explain why numbers of them happen to be in the window well.

If the bees you have described were emerging from burrows in the soil, they may be a kind of ground nesting bee rather than carpenter bees.
http://blog-yard-garden-news.extension.umn.edu/2015/04/ignore-andrenid-bees.html