I was stung multiple times (about 30) when I stepped in a hive about 10 years ago. I had no idea that they lived in the ground!! I'm not sure if they were yellowjackets or just regular bees but the pain was unbelievable!
We were cutting grass and I stopped my mower over one of their nests and I guess they didn't appreciate it....next thing I knew my legs were covered with them. Scared my DH to death!
Now, I pay attention to what's on the ground as well as what's flying around!