A South-central Kentucky man believed to be the leader of a conspiracy to grow more than 1,200 marijuana plants at his home has pleaded guilty this week in federal court in Bowling Green. Seventy-year-old Dallas Norris pleaded guilty to manufacturing and distributing a controlled substance, money laundering and possession of firearms by a felon. Prosecutors say Norris and 10 co-defendants operated a sophisticated marijuana growing operation that was discovered by Kentucky State Police at his Glasgow home last November. A police investigation determined that the operation started in 2008 and was producing seven to 10 pounds of marijuana about every two weeks.