Within a specific range of sizes and actions, plastic worms are the most versatile and most effective tools to use for smallmouths in lakes. The right worm is 4 to 5 inches long and relatively thin. It can have a finesse tail or an action tail. When smallmouths cruise the tops of shallow reefs, pitch a worm on a 1/16- to 1/32-ounce head and slowly reel it in. When smallmouths move deeper, deliver the worm on a drop-shot rig, Carolina rig, Texas rig or split-shot rig, as the cover and depth demands.