My mom got bit on the ankle by a King Snake...non poisonous. Her sister was bitten by either a Water Mocassin or Rattler -- I can't remember which one. It tore up the muscle around her ankle and she was very sick for awhile.
I've only seen Black snakes around our house. They are fast as shi* but non poisonous. I don't miss those nasty snakes in Louisiana.
Mom said the snake was a Cottonmouth.