A packet of envelopes can i take tylenol while pregnant for headache If you see a cloud of insects hovering over a hole in the lawn, a hollow tree or a gap in a wall, proceed with caution. If they are chubby and fuzzy, they’re probably peace-loving ground bees that mean you no harm. However, if they are the sleek and shiny wasp known as the yellow jacket, it’s best to steer clear.