Removing ground bee/wasps from backyard.
These could be ground dwelling yellow jackets. See info from univ. of Maryland:
Control info from Minnesota:
Yellowjacket ground nests
Nests in the ground can be controlled by placing an insecticide dust, typically containing permethrin, in and around the nest entrance during the night. The dust particles will adhere to the insects as they leave and reenter the nest and control will usually be achieved within a few days. Pouring a liquid insecticide into the nest entrance is less likely to be effective as the liquid may not reach the nest depending on where it is located within the burrow.Yellowjackets during late summer and fall
Late summer and fall is the time of year when populations of yellowjackets (often mistakenly called "bees") and other social wasps become large and noticeable. The wasps have been present since spring, but because colonies start as a single queen, populations are very small through the early part of the summer. Yellowjacket wasp populations peak during later summer when each nest may have up to approximately 5,000 wasps.
Some yellowjacket species become aggressive scavengers and can disrupt outside activities where food or drink are served (figure 23). Control of scavenging yellowjackets is difficult, as there are no insecticides that effectively repel or discourage them. It is possible to spray soapy water on individual yellowjackets to kill them.
Jeff Hahn, University of Minnesota
Fig. 23 Yellowjackets can be found around food and beverages during late summer and fall
The best strategy is to minimize attracting them.
- Wait to serve food and drink until people are ready to eat.
- Promptly put away food when done and throw garbage into a container with a tightly fitting lid.
- Examine glasses, cans, and other containers before drinking from them to check for yellowjackets that may have flown inside. If a yellowjacket flies into your food, wait for it to fly away or gently brush it away.
- If only a few yellowjackets are bothering your activity, ignoring them or capturing them with a net and crushing them may be sufficient.
- Traps may catch many wasps, but not enough are captured to noticeably reduce their activity in the fall.
Thank you for all your advice---we will proceed with this solution.