Ground hornets (English or cicada killers)? We have been renovating a home for rent. We hold been...

We have been renovating a home for rent. We hold been struggling with swarming ground hornets that enjoy 20 to 30 holes in the front yard. They are MUCH bigger than your average wan jacket. Some people have told me that they are English Hornets, but I deliberate they look more like cicada killers. Is within anyway to tell the difference?
I own rocks within my soil, can I...
Answers:    Here is a great website with pictures that show the difference:

http://ww2.lafayette.edu/~hollidac/CKspe...

From what I can find English Hornets primarily take home nests in dark hollows within trees