Those ground wasps are really nasty! The worst part is that you don't usually realize they are there until you're already getting stung
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We have a lot of actual "ground bees" (Colletes inaequalis) in our yard; they're very non-aggressive and have actually become our main pollinator -- in years past we had lots of bumblebees but they've diminished significantly since the really bad winter in 2013-2014, when the frost was a good 6' down in the ground and we had extended periods of below-zero temps.
This is a link to an article about ground bees:
https://entomology.cals.cornel...
