Minnesota · ranked from DNR surveys
Best largemouth bass lakes in Polk County
12 surveyed largemouth bass lakes sit in Polk County; the 6 ranked here cleared this site's grade rubric, which reads DNR survey catch rates, size structure and trophy history the same way the live map does for every lake.
Maple Lake leads at grade A−, with 62 largemouth bass per hour of electrofishing in its 2024 survey and a 15-inch fish the biggest measured. Union Lake is next at B−, 13% of the largemouth bass netted over 15 inches. Crystal Lake rounds out the top three at C+, a 16-inch fish the biggest measured.
| # | 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 this site's rubric over Minnesota DNR survey data (catch per unit effort against DNR benchmarks, size structure, trophy history). See any lake's page for the underlying numbers. Survey years vary by lake; the table shows each lake's latest.