TRI CITY — With membership dwindling, three Veterans of Foreign Wars posts in South County are merging, another sign that the Greatest Generation is passing. “We’re losing World War II members and the young people coming back aren’t joining veterans organizations,” said Air Force veteran Rich Garnsey, 74, of the Canyonville-South Umpqua Post. Pending approval at the state and national levels, the post will combine with the Glenn A. Cripps Post in Riddle and the Thacker-Wallace Post of Myrtle Creek and Tri City. The three posts will come together as the South Umpqua Thacker-Wallace Post 9744, which will have its …