I fished the lake years ago and remember it was when the locals told me that fishing was slow at the time there. I went into the reeds and worked them close. I got a lot of nice Northern with weedless spoons (Johnson Silver Minnows with a white Berkley Power Grub for a tail). I had such good luck that I stayed on the pattern all day and come evening I started taking walleyes in the reeds. The I switched to shallow diving raps and worked the edges. I never tryed a different pattern both days there and I was all alone with no other boats working the reeds.
Bass, Northern, and Walleyes all feed on the minnows that use the reeds as cover. Work not just the edges, but go into pockets and sometimes between the shore and where the reeds start… real shallow. The key is heavy line and weedless lures. Leaders are a must.
If you get there and there are no reeds (because of high water) look for stick-ups. You may find the submerged reed line shallow. Good luck on the Big “O”.
“Hoggie” Hoggard