FILE - This May 31, 1972 photo shows United Farm Workers leader Cesar Chavez, suffering from the effects of a 20-day hunger strike, as he's wheeled form his Phoenix, Ariz. barrio headquarters to be taken to a hospital. The National Park Service is conducting a study of sites significant to the life of Cesar Chavez and the farm labor movement in an effort to protect the areas for future public use and enjoyment. Chavez, who was born near Yuma and died in San Luis, Ariz., co-founded the United Farm Workers Union. (AP Photo)