Grassy

Grassy Lake is a 257 acre lake located 7 miles north of Ely. The lake has three accesses with the main access being a 1/4 mile portage from a small parking area off the Grassy Lake Rd to the northern most part of the lake. A water route access exists from Low Lake through the Range River, up Grassy Creek, and over a small portage to the southeast bay of Grassy Lake. The third access is a 200 yard portage to Tee Lake near Grassy's northwest end. The lake has a maximum depth of 15 feet and brown bog-stained water. On July 15, 2019 Grassy Lake was thermally stratified with a surface temperature of 77 F and a bottom temperature of 60 F. Oxygen levels were adequate for gamefish to a depth of 11 feet. Grassy has five small inlets and one outlet. The inlets all drain from nearby small lakes or wetlands. Grassy Creek is the lone outlet exiting out the lake's southeast side on its way to the Range River before heading north to Range Lake and then Basswood Lake. Lake bottom substrates along the shoreline are mostly boulder and ledge rock with muck in the bays. Aquatic vegetation is substantial in some of the bays and generally grows to around 5 feet deep. Remnant dead heads can be found throughout the lake but are more congregated in the outlet bay. Lake levels are prone to fluctuations due to beaver activity near the outlet. Nearly the entire lakeshore is US Forest Service owned land except for one private parcel on the lake's northeast corner. There are two Forest Service maintained campsites on the lake. The lake has only been stocked with black crappie, largemouth bass, and smallmouth bass. The last stocking event took place in 1954. The overall gillnet catch rate from this survey for all fish combined was 12.7 fish/net which was the second highest catch rate for Grassy Lake. Fish species sampled were northern pike, bluegill, smallmouth bass, black crappie, yellow perch, and largemouth bass. Trap nets caught fish at an overall rate of 32.2 fish/net which was the highest catch rate on record for the lake. Bluegill were the most abundant species caught in trap nets with no additional species sampled that weren't already observed in the gill nets. The northern pike gillnet catch rate was 5.5 fish/net which was second best out of the five surveys on Grassy Lake and above average compared to other similar lakes in the state. Sizes were decent with a range from 16 to 32 inches and an average of 22 inches, which was the highest on record for the lake. Nine smallmouth bass were captured in gill nets for a catch rate of 1.5 fish/net. This was below average compared to other similar lakes in the state, but by far the highest catch rate on record for Grassy. This catch rate was also quite good when compared to other smallmouth lakes in the Tower area. Sizes were very impressive with an average of nearly 17 inches and the largest fish measuring 18.5 inches. Ages ranged from 6 to 10 years old. A total of six largemouth bass were captured, three from each net type. The gill net catch rate of 0.5 fish/net was better than average compared to other similar lakes. Lengths ranged from 9 to 20 inches with an average of 14 inches. The largest fish sampled in the trap nets weighed just over 5.5 pounds. Aging fish based on scales can be difficult on large old fish, so the maximum age of some of the larger bass was not known. The bluegill trapnet catch was 25.6 fish/net which was the highest on record for the lake and well above average compared to other similar lakes, and other lakes in the area. Sizes ranged from 4 to over 9 inches with an average of just over 6 inches. Ages ranged from 2 to 11 years old with several strong year classes. Growth rates appear quite good however, it still takes 6 years for the average bluegill to reach 7 inches. Catch and release is encouraged especially on fish over 8 inches long. The black crappie trapnet catch was 3.9 fish/net which was above average compared to other similar lakes. Lengths ranged from 5 to 12 inches with an average of 8 inches. Ages ranged from 2 to 8 years with strongest year class coming from 2015. Growth rates are average compared to other crappie lakes in the area. As is the case with bluegill, catch and release is strongly encouraged for black crappie, especially on the larger sized fish. The yellow perch catch rate was 0.8 fish/gill net which was below average for the lake. A total of 10 perch were sampled with an average length of 6.5 inches and a max of 9 inches.

Grassy Lake is in Ecological Lake Class 12, which consists of 90 lakes in northeast Minnesota that are average in size, are very shallow, have irregularly shaped shorelines, and have very soft (unmineralized) water. Grassy Lake ranks as mesotrophic according to Carlson's Trophic State Index. Grassy Lake was thermally stratified on 06/11/2007 with a surface temperature of 69 F and a bottom temperature of 61 F. Adequate oxygen for fish (more than 2 ppm) was retained to the bottom. The main inlet is from Tee Lake and the outlet is to the Range River; there are beaver dams and rocky drops limiting fish movement in the inlets and outlet. Bottom substrates consist mostly of muck, silt, and boulder. Aquatic plants grow to a depth of 6 ft, with concentrations in the inlet and outlet bays. The most common plants are watershield, milfoil, waterlilies, floating leaf burreed, and bladderwort. Lands administered by the U.S. Forest Service surround all of Grassy Lake except for a private parcel on the northeast shore that is accessed by a private road off the Grassy Lake Road (Forest Road 459). Public access is by a 0.25 mile portage to the northwest shore of Grassy Lake from a parking area that is 0.9 miles south of the Grassy Lake Road. Other accesses include a portage from Tee Lake and a portage from the Range River via Low Lake. The 2007 fisheries lake survey sampled fish populations with six gillnets, nine standard trapnets, and four small mesh (1/4" bar) trapnets. Previously, a fisheries lake survey (1975) and two fish population assessments (1985, 1997) were conducted on Grassy Lake. These previous investigations used 3-6 gillnets and 4-9 trapnets. The total catch of fish (all species combined) in the gillnets in 2007 of 6 fish/net (11 lb/net) was in the first quartile for this lake class, and was similar to the median total catch of 8 fish/net (9 lb/net) in all investigations on this lake. The total catch of fish in the trapnets in 2007 of 20 fish/net (13 lb/net) was similar to the median total catch of 19 fish/net (12 lb/net) in previous trapnettings on this lake. Fish populations in 2007, as in previous investigations on this lake, were dominated by northern pike and bluegill, followed by black crappie and largemouth bass. Notable by their absence in this investigation (and by their presence in very low numbers in previous investigations) were white sucker. Northern pike numbers in 2007 (4.5/gillnet) were in the third quartile for this lake class and were similar to the median pike catch of 3.9/gillnet in all investigations on this lake. Pike sizes in 2007 averaged 21.4" (2.5 lb), which was in the fourth quartile for this lake class and was similar to the average size of 20.3" in all investigations on this lake. The largest pike was 36.6". Pike scales were difficult to read, but pike growth appeared to be slower than normal (in the first or second quartile, depending on the age) by area standards. Bluegill numbers in 2007 (16.0/trapnet) were in the fourth quartile for this lake class and were similar to the median bluegill catch of 13.3/trapnet in all investigations on this lake. Bluegill sizes in Grassy Lake have increased over time and in 2007 averaged 7.8" (0.43 lb), which was in the fourth quartile for this lake class. Forty nine percent of the bluegill were 8" or larger and the largest was 9.9". Bluegill growth was faster than normal by area standards. Black crappie numbers in 2007 (2.1/trapnet) were in the second quartile for this lake class and were similar to the median crappie catch of 2.2/trapnet in all investigations on this lake. Crappie sizes in 2007 averaged 9.4" (0.46 lb), which was in the third quartile for this lake class and was similar to the average size of 9.0" in all investigations on this lake. Crappie growth was somewhat faster than normal by area standards. Largemouth bass are likely more abundant than indicated by trapnet and gillnet catches. Bass are "net shy" and tend to avoid standard sampling nets. The largest largemouth captured in 2007 was 17.9". Largemouth growth appeared to be faster than normal by area standards. The game fish examined in 2007 were remarkably free of diseases or parasites. Only two fish had neascus (black spot). Neascus is a common parasite that is native to the area. It cannot infect humans, is often removed by filleting fish, and is killed at temperatures used to cook fish.

Grassy Lake is very typical of lakes in Ecological Lake Class 12, which consists of 90 lakes in northeast Minnesota that are average in size, are very shallow, have irregularly shaped shorelines, and have very soft (unmineralized) water.Grassy Lake partially stratifies thermally in midsummer and retains good oxygen (2 ppm) to within a few feet of the bottom, where the temperature is in the low 60's F. The main inlet is from Tee Lake and the outlet is to the Range River. Lake bottom substrates along the shoreline consist mostly of muck, ledgerock, and boulder. Aquatic plants grow to a depth of 6 ft and consist mostly of waterlilies, milfoil, spikerush, and bulrush.The total catch of fish (all species combined) in the gillnets in 1997 of 17 fish/net (12 lb/net) was lower than normal for this lake class, yet was higher than previous gillnet catches on this lake in 1975 and 1985. The total catch of fish in the trapnets in 1997 of 24 fish/net (12 lb/net) was similar to the average catch of 19 fish/net (12 lb/net) in previous trapnet catches on this lake.Fish populations in 1997 were dominated by northern pike and bluegill sunfish, followed by black crappie and largemouth bass.Northern pike numbers in 1997 (6/gillnet) were normal for this lake class, but were higher than previous catches of 3/gillnet in 1975 and 1985. Pike sizes in 1997 averaged 19", which was similar to previous catches. The largest pike caught in 1997 was 28". Pike recruitment was spread among many year classes. Pike growth (21" at age four) was normal for the area.Bluegill numbers in 1997 (10/trapnet) were higher than normal for this lake class, but were similar to previous catches of 11/trapnet in 1975 and 16/trapnet in 1985. Bluegill sizes in 1997 averaged 8", which was larger than in previous catches. The largest bluegill in 1997 was 10". Few bluegill were produced during the cold summers of 1992 and 1993, something we have observed in many area lakes. Bluegill growth (6" at age three) was normal for the area.Black crappie numbers in 1997 (7/trapnet) were normal for this lake class, but were higher than previous catches of 1/trapnet in 1975 and 2/trapnet in 1985. Crappie sizes in 1997 averaged 8", which was smaller than in previous catches. The largest crappie in 1997 was 11". No crappie were produced during the cold summers of 1992 and 1993. Crappie growth (6" at age three) was normal for the area.Yellow perch numbers in 1997 (6/gillnet) were normal for this lake class, but were higher than previous catches of 2/gillnet in 1975 and 3/gillnet in 1985. Perch sizes averaged 6"; the largest was 8". Perch growth (5" at age three) was normal for the area.Largemouth bass numbers in 1997 (4/trapnet) were higher than in previous trapnettings on this lake. Largemouth sizes in 1997 were small, averaging 10"; the largest was 16". Largemouth growth (10" at age three) was faster than normal for the area.Low numbers of hybrid sunfish, smallmouth bass, and white sucker were also observed in 1997. Pumpkinseed sunfish, previously observed in 1985, were absent in 1997.

Based on Minnesota DNR survey data, anglers target Bluegill, Northern Pike, Black Crappie, Smallmouth Bass, and Largemouth Bass in Grassy. See the full species list above for catch rates, size structure, and quality scores.

Minnesota DNR records list public access for Grassy. Check the DNR LakeFinder page for the launch type and directions before you go.

Grassy has a maximum depth of 15 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Grassy is from 2019.

No invasive species are on record for Grassy in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.