ARIVACA, Ariz. -- Jim Chilton is one of hundreds of ranchers targeted by environmental groups for allegedly allowing cattle to despoil the West's backcountry. Now Mr. Chilton is showing ranchers how to turn the tables on the green groups by using their own playbook. The Center for Biological Diversity in Tucson is known for its lawsuits against ranching practices -- and for its methods of posting photos on the Internet that it says depict land destruction. So when the Center came after Mr. Chilton, he struck back with a defamation suit in Arizona Superior Court in Tucson last year....