Minnesota · ranked from DNR surveys
Best largemouth bass lakes in Polk County
The DNR has surveyed largemouth bass in 12 lakes in Polk County. The 6 ranked below are the ones that earn a grade on this site. Grades come from survey catch rates, fish size and trophy history, scored the same way for every lake on the live map.
Maple Lake is first at A−. The DNR caught 62 largemouth bass per hour of electrofishing in the 2024 survey, and the biggest was 15 inches. Union Lake is second at B−. 13% of its largemouth bass measured over 15 inches. Crystal Lake is third at C+, and its biggest largemouth bass was 16 inches.
| # | Lake | Grade | Acres | Survey catch rate | Over 15" | Biggest Surveyed | Avg wt | Surveyed |
|---|---|---|---|---|---|---|---|---|
| 1 | Maple Lake | A− | 1,641 | 62/hr in electrofishing | 100% | 15" | 2.2 lb | 2024 |
| 2 | Union Lake | B− | 888 | — | 13% | 18" | 1 lb | 2022 |
| 3 | Crystal Lake | C+ | 118 | — | 75% | 16" | 1.9 lb | 2025 |
| 4 | Spring Lake | C+ | 134 | 29.9/hr in electrofishing | 0% | — | — | 2023 |
| 5 | Sarah Lake | C+ | 366 | — | 0% | 5" | 0.1 lb | 2021 |
| 6 | Badger Lake | C+ | 256 | — | 0% | 10" | 0.3 lb | 2016 |
Also ranked in Polk County: Walleye · Northern pike · Crappie · Bluegill · Yellow perch
All of Minnesota: Best largemouth bass lakes in Minnesota
Grades are based on Minnesota DNR survey data: how many fish the DNR caught (scaled by lake size), how many reached quality size, and the biggest fish measured. Each lake's page has the numbers behind its grade. The table shows each lake's most recent survey year.