In addition to below see here.
Extract from Snakes of Alabama: How to identify all 50 species
Snakes you might come across in Alabama
Alabama is home to six venomous snakes. The Eastern Coral Snake, Copperhead, Cottonmouth, Eastern Diamondback, Timber Rattlesnake and Pygmy Rattlesnake. the eastern coral snake packs the most potent venom of all.
A Guide to Alabama’s Venomous Snakes