"At certain seasons large bass, like the smaller fish, will school and lay up close to bottom structure (a bottom depression, ridge, rock heap, weedline, river channel, etc.). Deep fishing for such schools normally is necessary in very early spring (the pre-spawn period), and in summer (post-spawn period).
I well remember a chilling day in May on Lake Marie, a hard-fished body of dingy water only 30 miles north of Chicago. I was fishing with Buck Perry of Hickory, North Carolina, the deep-water structure fishing expert, and Don Nichols and John Buoy of Chicago. Trolling with deep-going, bottom-scratching spoons 20 feet down along structure Buck had located, we caught nearly two dozen bass - each of which was right around 6 pounds! The fish obviously were all of a single year-class."