My Decatur County Surnames: Wilson - Decatur County near Lineville & Mercer Co, Mo. Adair - Decatur County near Lineville & Mercer Co. Mo. Beavers - Decatur, Co. Clark Coontz Harshbarger Riddle Mackey - Decatur, Co. Mercer, Co. Mo. Newlin - Decatur, Co. McClarnon, Stewart, Vance, Mothershead,Clayton and many more George Wilson Idaho