In mid-1971, I experienced a most distressing visit to the dentist.

A TV fan magazine in the waiting room divulged life-changing news. Irene Ryan (who portrayed Granny on “The Beverly Hillbillies”) told an interviewer she was madder than a wet hen -- because CBS had canceled the beloved sitcom after nine seasons!

TV historians regard this as part of the “rural purge” of the early 70s. “Petticoat Junction” and “The Jackie Gleason” show had disappeared a year earlier, and “Bonanza” and “Gunsmoke” would hang on until 1973 and 1975 respectively; but fall 1971 was the epicenter of a major upheaval...