Prairie Sportsman

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Host

Minnesota, home to big lakes, small lakes, winding rivers and shallow creeks. The state offers a wide variety of fishing options for the different species that swim through those waters. Certain species such as large mouth bass, fair better in the warmer lakes. While lake trout prefer the opposite. In a few rare cases, you can find them both in the same body of water. These are called two-story lakes. One of them is Grindstone Lake in Pine County. I set out with my brother Wade to find out exactly what a two-story lake is and to see if we get catch fish from both stories. (upbeat music playing) So, this is a lake that Wade and I wanted to fish for a long time. We've talked about it for a long time. It's only an hour and a half north of the twin cities. And it's a trout lake, which you don't have a lot of options for trout lakes this far south in the state. Normally, got to go up to, say, lake superior up around that Ely area or some of the other stock stream trout opportunities across the state. But this one is 153 feet deep. There's lake trout in here. There's brown trout, rainbow trout, but what really makes it unique body of water is, is it's not only a deep cold, clear lake that supports those trout species but it also is a what's called a two-story lake. So it support some of those warmer shallower water fish species as well, like panfish, crappies, bluegills, as well as bass. So we're going to try to catch some deeper cold water fish. Hopefully a lake trout. And then also try to fish the shallow waters so we can experience both stories of Grindstone Lake. Christ don't like to pretty unique lake you know, we're, you know- in East Central Minnesota. I guess the closest town would be Sandstone which is about four miles east to here, Sandstone, Minnesota. And a lot of people come here and sometimes they're intimidated by the lake but it's actually a really, really unique fishery. And it does get a fair amount of pressure during the- all year to be honest with you. It is hot. I don't know what the exact temperature is but if I were to guess, I'd say like probably around 350 degrees. It's warm one out here. It's glass calm. It's beautiful. This is a pretty neat Lake. It's about two miles running north to south, a couple of deep spots and get down to about 150 feet, 160 feet in there somewhere. And you just don't see lakes that deep this far south. A lot of these lakes, you find up the north shore the Gunflint Trail, or, you know, further north than that. So it is unique and it is something that, I think a lot of people overlook when, when they come to this areas. They just look at it as all another warm water lake, right? You wouldn't expect to catch trout in the lake this far south in the state, just because of the weather, but, but it's so deep, you know, that we're able to maintain those temperatures for trouts. And to have lake trout, brown trout, rainbow trout, all in this real deep clear cold body of water is a, is a pretty neat experience here in Minnesota. I just wish it wasn't as hot as the surface of the sun, right now. (in high voice) I'm melting. -

Host

So how does a two-story fishery work? So two-story fishery is different than your traditional lakes in Minnesota. There, there's a handful of them around the state but you know, Grindstone Lake gets to be about 150 foot deep. With all that water, you'll have a thermal climate in the middle where the sun can only penetrate so far down. And it kind of presents that warm water fishery above the thermal climate, which is about 30, 40 feet down. And then underneath that, you know, where the sun doesn't penetrate as much, you have cooler water. It's really unique because you can have your warm water fishery, you know, bass, pike, panfish, that kind of thing on the top, but you can also hold the- a trout fishery or cold water fishery underneath the thermal climate. It's kind of a challenge managing the lake sometimes just because there are so many different species in there. -

Host

Grindstone Lake is stocked with lake trout, rainbow trout and brown trout. -

Nate

Back in the day, historically, they- they tried to stock them to see if they could get them to naturally reproduce and they never really took off. The lake is filled with like hard-shelf rock and not a lot of gravel rubble substrate for spawning. So, you know, the idea is, you know put a bunch of trout on there and they'd be able to reproduce and they'd be good to go but they just never been able to really do it. They- there may be a little bit of natural reproduction going on but not enough to sustain a fishery, so. So we stock them, annually. We stock rainbows and browns every year and lake trout every other year. (upbeat music playing) -

Host

It seemed as though the heat was affecting the fish as much as the fishermen. It was time to try something different. So we've been fishing the basement of the two-story, now we're gonna go upstairs and fish the warmer water part of the lake. But first we got to cool off just a little bit. (upbeat music playing) -

Bret

So we just came off in the landing here and the dry- it drops off from about two feet to about 30 feet right away. We're just going to take that drop-off now. And we're going to pull either some little maps or maybe some small crank baits and we're gonna try to stay in that 30 to 50 foot range and just kind of troll around the lakes. See if we can find them. Try to stay running underneath that thermal climb a little bit in the cooler water. -

Host

While the lake is managed for trout, it's not listed as a designated trout lake. And it's also becoming more popular for other fish species. You know, we're managing the trout lake in the warm water fish, you know, they're kind of on their own, but that's actually really taken off the last five or six years. There's a pretty good population of small molls in here. I think in our last survey, we surveyed 50 or 60 per hour at electro fishing and they're decent size. And there's four or five artificial cribs scattered around the lake that attract people as far as bass and crappies and that stuff. And I know there's guys out here that troll exclusively for trophy pipe. And it's not uncommon to maybe see a 40- 40 inch out here every once in a while too, so. -

Host

While Grindstone Lake's two-story characteristics make it possible to have a wide variety of species in it, the state fish is suspiciously absent. Back in the day, historically, just never had them in there. And I think we'd all agree we have quite a few walleye lakes around on the area, wondering if one more species might throw the balance off a little bit. In, in our files, we don't show any walleyes that rent here, but some of the landowners people around here will tell me that they used to be walleyes in here, but we haven't sampled one in our surveys. And well, I don't think ever. Yeah, so don't, don't come here to expect to catch walleyes. You'll be disappointed. -

Host

Since there haven't been walleyes here, the decision to make this a trout lake happened right away. -

Nate

You know, probably back in the 1940, it's kind of funny that, you know, you go out here and you've got 150 foot of cold water, you know, and there's, and there's no trout in here. So it made perfect sense to try to stock trout in here, right? You know, this one speaks for itself. I mean, in the winter time, the ice fishing, the first couple of weeks after the trout opener it- it's not uncommon to see three, 400 portable shelters out there for the trouts. -

Host

There are a handful of two-story lakes in the state of Minnesota, including Grindstone. Having the opportunity to target that many different species in one body of water is another uniquely Minnesotan adventure.