Fall is an excellent time to catch big walleye and weed lines are the key.  
Veteran walleye guide Mike Christensen has discovered the weed bed theory around his home waters of mighty Mille Laces Lake, located roughly 100 miles north of Minneapolis, Minn. It’s there he runs ice and open-water walleye adventures out of Hunter Winfield's Resort.
Fertile weed beds are often overlooked. The same scenario arises in natural lakes with an abundance of shoreline vegetation. The reason behind walleyes' fondness for fall greenery is simple — it holds food. Weeds often attract a variety of minnow species, young perch, sunfish and crappie offering hungry predator fish an easy meal. This is a proven fact in Minnesota that has been re-proven many times throughout the Midwest.
Not all weed beds are created equal. Christensen says that green live weeds are key, and broad-leafed pondweeds, commonly called cabbage, are the cream of the fish attracting crop. Some of the very best weed beds often lie close to deep water, and offer walleyes easy access. These weed beds are even better if they exist in combination with structure such as a change in bottom composition or a rock pile.
“When you find weeds on a point jutting out into deeper water, you're really in business,” Christensen says. “Key depths for prime vegetation commonly range from five to 12 feet.”
It's possible to pluck plump walleyes from pockets in the weeds, but Christensen prefers the deadly efficiency of commercial harnesses called Lindy rigs. His go-to rig includes Lindy's 72-inch Minnow Shell, which he says helps avoid spooking skittish walleyes.
“Both the inside and outside edges of the weed line can hold fish,” he said. “I often start deep. If the fish are really biting and all of a sudden disappear, I'll move to the inside edge. Often, active fish move shallower, so you have to move with them to stay on the bite.”
When the water is off-color to flat out murky, he will opt for the 42-inch Lindy Rig X-Treme or the 36-inch Minnow Snell. Slip-sinkers such as the Lindy Walking Sinker or No-Snagg are key to weed line success because they allow the fish to take line without feeling the weight of the sinker. Christensen matches sinker weight to water depth and other factors, such as wind and waves.
“Always go as light as possible to maintain bottom contact with your line at a 45-degree angle to the water,” he says. “You don't want your minnow to lift the sinker off bottom and swim away from walleyes.”
In general, sinkers in the 3/8-ounce range are mainly used in the depths Christensen targets. Chubs are the bait of choice.
“They're tough little minnows that remain lively a long time — much longer than shiners,” he says. “Leeches are another decent option, but they're hard to find in fall, especially in the Midwest. Nightcrawlers are better earlier in the year, when there are more bug hatches going on.”
Standard rigging calls for nose-hooking the bait, though at times hooking the minnow lightly near the dorsal fin works. Christensen slow-trolls the rig along weed lines powered only by his trolling motor.
“I occasionally find fish with my sonar, or watch my line to see my minnow swimming around more than usual, showing a walleye is moving in for a closer look,” Christensen said. “In either case, I slow down to give the fish more time to take the bait. I often turn around for another pass at the prime area.”
It can be challenging to detect the strike and get a good hook-set when the sinker is ticking along a soft, weedy bottom and occasionally hanging up on weed clumps and stalks. To tip the odds in his favor, Christensen fishes with a light-tipped rod, which loads up nicely when faced with resistance and gives him a chance to determine when extra weight is a light-biting walleye or simply vegetation.
“Let the rod load up to be sure it's a fish,” Christensen says. “Sometimes you'll also feel a twitch or thump when a walleye grabs the minnow, but not always.”
Knowing a fish has the bait is half the battle. Sticking the hook in its jaw is the other. After detecting a bite, Christensen feeds the fish slack line, and then typically gives it a little time to get the minnow in its maw before driving the hook home.
Most often, it's an amazingly calm 10-count, though fish activity level may dictate longer or shorter counts. He says that he knows anglers who wait a minute or more to set the hook, but that can lead to deeply hooked fish.
“I release most of my fish, so I don't wait that long,” he notes.
When it's time to set the hook, don't just snap the rod back and hope for the best. Instead, gently reel up any slack in the line until the rod loads up and you feel the weight of the fish, then execute a nice, strong, sweeping hook-set.