<human>: I live in a neighborhood where a couple houses just let their dogs roam free. Lately two of these dogs have taken up the habit of pooping on the outside perimeter of my lawn (I have a fence)  and I've stepped in it on more than one occasion. 

I have a small Shih Tzu as well that likes to run around the inside the perimeter of the fence so  would like some suggestions on how to safely and successfully repel and discourage their dogs from pooping on my lawn without harming any of our dogs. Talking to said neighbor is useless as he's been letting his two dogs run free since he moved in a year ago. nobody is home half the day to chase them away either.

Can you give me a shortened version of the text?
<bot>: I keep stepping on neighbor's dog shit on my own lawn. How do I safely discourage dogs from going on my lawn?