My husband would put up a similar sign . . .his lawn is his masterpiece along with his flower beds and islands . . .and there are several people who walk their dogs in our neighborhood that pay no mind to where their dog poo's. He just doesn't like to be cutting the lawn and have to step on a mound . . .it would ruin his entire day . . .then I'd have to listen to him for the rest of the night . . .
