Minnesota · Pine County
Grindstone Lake Fishing guide
Grindstone Lake covers 533 acres in Pine County, Minnesota, reaching 153 ft at its deepest point. Secchi readings average around 10.7 ft of visibility. The Minnesota DNR has surveyed the lake 15 times, most recently in 2025, with largemouth bass, smallmouth bass, northern pike and bluegill in the nets.
DNR survey data
Fish species
Largemouth bassJust a few17.5per hr (electrofishing)8"Typical18"Biggest
Lengths measured · 69 fish
Recent · 2025Lengths measured · 69 fish
2025Lengths measured · 2 fish
2024Only 2 fish measured that year — too few to read as a shape.
Lengths measured · 11 fish
2016Lengths measured · 7 fish
2012Only 7 fish measured that year — too few to read as a shape.
Smallmouth bassGood numbers27.2per hr (electrofishing)6"Typical18"Biggest
Lengths measured · 101 fish
Recent · 2025Lengths measured · 101 fish
2025Lengths measured · 3 fish
2024Only 3 fish measured that year — too few to read as a shape.
Lengths measured · 5 fish
2020Only 5 fish measured that year — too few to read as a shape.
Lengths measured · 75 fish
2016Northern pikeJust a few1.6per gill net21"Typical33"Biggest
Lengths measured · 52 fish
Recent · 2022 + 2025Lengths measured · 45 fish
2025Lengths measured · 1 fish
2024Only 1 fish measured that year — too few to read as a shape.
Lengths measured · 7 fish
2022Only 7 fish measured that year — too few to read as a shape.
Lengths measured · 15 fish
2020BluegillJust a few11.8per trap net5"Typical9"Biggest
Lengths measured · 1223 fish
Recent · 2025Lengths measured · 1112 fish
2025Lengths measured · 111 fish
2025Lengths measured · 161 fish
2016Lengths measured · 265 fish
2012CrappieJust a few1.1per trap net7"Typical14"Biggest
Lengths measured · 229 fish
Recent · 2025Lengths measured · 210 fish
2025Lengths measured · 19 fish
2025Lengths measured · 1 fish
2024Only 1 fish measured that year — too few to read as a shape.
Lengths measured · 27 fish
2016Present and managed by the DNR.
Present and managed by the DNR.
Present and managed by the DNR.
Lake troutLast stocked 2025Present, stockedPresent and managed by the DNR.
Present and managed by the DNR.
Lengths measured · 25 fish
Recent · 2022 + 2025Lengths measured · 1 fish
2025Only 1 fish measured that year — too few to read as a shape.
Lengths measured · 12 fish
2025Lengths measured · 12 fish
2024Lengths measured · 12 fish
2022Rock bassGood numbers1.3per trap net6"Typical12"Biggest
Lengths measured · 28 fish
Recent · 2025Lengths measured · 28 fish
2025Lengths measured · 13 fish
2016Lengths measured · 29 fish
2012Lengths measured · 28 fish
2007Rates come from standard DNR survey gear (gill nets, trap nets, electrofishing), judged against statewide benchmarks for the same gear, so the same number of fish per net can read differently for two species. Where the standard gear can't count a species reliably, only presence and size are listed. Typical is the middle fish of those measured. Open a row for the full length spread, survey by survey.
How to fish Grindstone Lake through the year
Smallmouth bass
- Spring
- Smallmouth are on shallow rock, gravel and sand where they spawn. At 10.7 ft of clarity, fish them deeper and lighter than usual.
- Early summer
- Smallmouth are post-spawn on rock points, gravel bars and the adjacent breaks.
- Summer
- Smallmouth are on rock humps, points and hard-bottom breaks. On a lake that drops to 153 ft, check the deep edge of that structure too.
- Fall
- Smallmouth are bunched tight on deep rock, so find one and you have found the school.
Largemouth bass
- Spring
- Largemouth are moving up into the warming bays and flats, staging around wood, docks and new weeds to spawn. At 10.7 ft of clarity, fish them deeper and lighter than usual.
- Early summer
- Largemouth are on the shallow spawning flats and protected bays, where beds go on firm bottom next to isolated cover.
- Summer
- Largemouth are in and along the weeds: cabbage and milfoil edges, matted cover and shade. On a lake that drops to 153 ft, check the deep edge of that structure too.
- Fall
- Largemouth are chasing bait back onto the flats and into the remaining green weeds, feeding hard and shallow before the freeze.
Season patterns for each species. Open the live map for today's wind, light and water temp.
Size history
Biggest fish by survey year
| Survey year | Smallmouth bass | Largemouth bass | Northern pike |
|---|---|---|---|
| 2025 | 18" | 18" | 33" |
| 2024 | 6" | 2" | 22" |
| 2022 | — | — | 32" |
| 2020 | 17" | — | 32" |
| 2016 | 18" | 15" | 31" |
| 2012 | 17" | 20" | 32" |
| 2007 | 19" | — | 32" |
| 2002 | 15" | — | 33" |
Longest fish measured by DNR survey crews in each year's nets. Survey gear samples the population, so the lake usually holds larger fish than any survey measured.
Suggested tackle
What to bring
Top presentations for this lake's structure and clarity:
Smallmouth bass · Soft plastics
Drop Shot (Finesse Plastic)
4" finesse worm or 3" minnow-profile plastic
Smallmouth bass · Jigs & bladed
Tail Spinner
Compact lead body with a free-spinning blade on the tail
Largemouth bass · Soft plastics
Texas-Rigged Worm
7" ribbon-tail or straight-tail plastic worm
Largemouth bass · Soft plastics
Free Rig
Creature bait or magnum finesse worm
Northern pike · Soft plastics
Paddletail Swimbait on Jighead
4–5" paddletail swimbait on a ball-head swimbait jighead
Northern pike · Muskie & pike
Soft Rubber (Bull Dawg / Medusa)
10" soft rubber body bait
Full setups, including hooks, weights and line, are on the live map. As an Amazon Associate I earn from qualifying purchases.
DNR stocking records
Stocking history
| Year | Species | Stocked |
|---|---|---|
| 2025 | Brook Trout | 977 adults |
| 2025 | Brown Trout | 350 fingerlings · 2,150 yearlings |
| 2025 | Lake Trout | 4,369 fingerlings · 5,250 yearlings |
| 2025 | Rainbow Trout | 9,000 yearlings · 702 adults |
| 2024 | Brown Trout | 2,500 yearlings |
| 2024 | Rainbow Trout | 9,000 yearlings · 112 adults |
| 2024 | Splake | 10,454 fingerlings |
| 2023 | Brown Trout | 953 fingerlings · 1,637 yearlings |
| 2023 | Lake Trout | 6,000 yearlings · 87 adults |
| 2023 | Rainbow Trout | 9,000 yearlings · 30 adults |
| 2022 | Brown Trout | 2,500 yearlings |
| 2022 | Rainbow Trout | 12,000 yearlings · 47 adults |
Stocking records before 2022 omitted.
MN DNR · in their words
From the 2025 survey
A targeted survey of the nearshore fish community was conducted by Hinckley fisheries staff on Grindstone Lake on August 4, 2025. Nearshore sampling captured 19 species of fish: Black Crappie, Bluegill, Bluntnose Minnow, Common Shiner, Creek Chub, Fathead Minnow, Golden Redhorse, Greater Redhorse, Iowa Darter, Johnny Darter, Largemouth Bass, Pumpkinseed, Rock Bass, Shorthead Redhorse, Smallmouth Bass, Spottail Shiner, White Sucker, Yellow Bullhead, and Yellow Perch.
The nearshore survey data is combined with standard gill and trap netting survey data from previous Grindstone Lake surveys to calculate a Fish IBI (FIBI) score and helps assess aquatic life in Grindstone Lake. The FIBI score for Grindstone Lake based on this survey is above the impairment threshold for aquatic life use determined for similar lakes.
This survey is contributing to a watershed assessment process in coordination with the MN Pollution Control Agency. For additional information on the FIBI, search for "lake index of biological integrity" on the mndnr.gov website.
Narrative text from the Minnesota DNR lake survey.
Recent reports
Grindstone Lake fishing reports
Recent reports on Grindstone Lake from guides, tournaments and regular anglers. Anything posted in the last two weeks also bumps the matching spots on the live map, so you'll see a "matches a recent report" tag on them.
Public water access
Getting on the water
- Grindstone Lake (trailer launch)
DNR bathymetry
Grindstone Lake depth map
Within 30 miles
Nearby lakes
- Bass Lake · 229 ac · 3 mi
- Eleven Lake · 315 ac · 3.8 mi
- Upper Pine Lake · 233 ac · 4.6 mi
- Indian Lake · 77 ac · 5.5 mi
- Pine Lake · 378 ac · 5.5 mi
- Fish Lake · 185 ac · 5.9 mi
- Big Pine Lake · 399 ac · 6.2 mi
- Five Lake · 44 ac · 6.5 mi
Quick answers
Frequently asked questions
How deep is Grindstone Lake?
Grindstone Lake reaches 153 ft at its deepest point with a mean depth of 60 ft; about 13% of the lake is littoral (15 ft or shallower).
How big is Grindstone Lake?
Grindstone Lake covers 533 acres with about 5 miles of shoreline.
How clear is the water in Grindstone Lake?
DNR Secchi readings on Grindstone Lake average 10.7 ft of visibility, clear water for a Minnesota lake.
What fish are in Grindstone Lake?
Minnesota DNR surveys (most recently 2025) record largemouth bass, smallmouth bass, northern pike, bluegill, crappie, yellow perch, brook trout, rainbow trout, brown trout, lake trout, rock bass.
Is Grindstone Lake stocked?
Yes. The DNR stocked brook trout, brown trout, lake trout and rainbow trout in 2025; the stocking table on this page lists every year back to 2022.
Does Grindstone Lake have a public access?
Yes. Grindstone Lake has one public access site: Grindstone Lake (trailer launch).
How big do smallmouth bass get in Grindstone Lake?
The biggest smallmouth bass measured in recent DNR surveys taped 18"; the size-history table on this page tracks the biggest fish in each survey back to 2002.
When was Grindstone Lake last surveyed?
The Minnesota DNR last surveyed Grindstone Lake in 2025, the most recent of 15 surveys on record.
Page updated .
Featured guide spot
Your guide service here
One featured guide per lake, with your photo, your writeup and a link straight to your booking page. Free through December 31, 2026.
Then $20 a month from January. Cancel any time.
The live map adds today's conditions and ranked spots for Grindstone Lake, plus a trip plan you can share:
Open Grindstone Lake on the live map → Fished it lately? Write a report