Also, if they're yellow jackets, they dig nests in the ground, so you may have a yj nest IN your run.  Check the ground carefully for holes anywhere from the size of a nickel to the size of a golfball.  I used to think they were snake holes ... NOPE.  Yellow jacket nests.  
They REALLY hated it when I went over the top with the lawn mower.
	
		
			
		
		
	
				
			They REALLY hated it when I went over the top with the lawn mower.