The bumblebees can make quite a tunnel before you get to the actual nest. Which is probably why the spray doesn't work. They probably won't bother anyone. If you're really determined, you can keep spraying, but you probably won't ever get the queen anyway, and as long as she's able to lay eggs and produce foragers, you're fighting a losing battle. As long as they are not hornets or yellowjackets, you're just wiping out a benficial insect. They aren't inclined to sting and they are good pollinators

I suppose I need to ask why this need to kill bumblebees that have caused no harm and sting no one.

They're docile unless attacked. They do valuable work.

By the way, honey bees will contribute an estimate $20 billion to our economy this year in increased crop yield. Bumblebees, Leaf cutter bees and others will add even more.

To Whom It May Concern:
Are These Bees in the sand are the same ones under the sidewalk. They are grey and very small and I can walk around them and they don't even bother me. What would they be called ?
I tried looking for a Bee Picture but, I can't find one.
They have many holes in the ground. I did not noticed they were going into the ground until I took out the tack weeds. The next day I seen them and the next day again. I wounder why they were hanging around. So, I looked more closely and they were going underground in the sand. Is thier any way to handle these guys. Because; next week I will be planting new Grass.
Hope to hear from you soon.

A.J.