If that doesn't do the trick, try a special tactic. Fasten a two-ounce bell sinker to the end of the line, like a drop-shot rig, and tie a loop in the line about a foot above it. Next, tie a 12-inch length of heavy mono leader to the loop and tie a weedless leadhead jig to the other end. Worm on a curly-tail grub to the jig and you're ready to go. To fish this rig, first make a high, towering cast with the sinker so that when it lands it will blast its way down through the weed blanket and into the opening below. Let the lure go to the bottom and twitch it back to the top, very slowly. Set the hook when you feel a tick or sense the slightest change in line tension.