A group of mostly-immigrant workers at a meat-packing plant in Buffalo Lake turned down a chance to unionize today. Union organizers charge some workers at the Minnesota Beef Industries plant were threatened or intimidated into not voting to unionize. Minnesota Beef would not comment on the matter. An increasingly large immigrant labor force is changing the way Minnesota's meat-packing plants do business -- and the wages they're willing to pay. Katherine Fennelly (FENN-a-lee) is a professor specializing in immigration and public policy at the Humphrey Institute at the University of Minnesota. She says immigrants are doing work that others won't.