Greenstone

Greenstone Lake is located 10 miles east of Ely. There are four accesses that are all remote carry-ins. Accesses consist of a 3/4-mile portage from Madden Lake, a 1/2-mile portage from the North Kawishiwi River, a winter snowmobile route to Pickerel Lake, and the trail system off the Madden Creek Rd. This 332-acre lake contains four inlets and one outlet, which flows to Pickerel Lake. Greenstone Lake has a maximum depth of 72 feet and brown bog-stained water. On September 17, 2024, Greenstone was thermally stratified with a surface temperature of 70 F and a bottom temperature of 45 F. Oxygen levels were adequate for gamefish to a depth of 22 feet where the temperature was 58 F. Lake bottom substrates along the shoreline of Greenstone Lake are mostly boulder and rubble. Aquatic plants are sparse and only grow in some of the shallow bays. There are a handful of water-access-only cabins on the lake, the shoreline is quite undeveloped overall. The overall gillnet catch rate for all fish combined was 13.8 fish/net which was above average for the lake. Yield was 20.4 pounds/net which was also above average. Fish species sampled were walleye, northern pike, rock bass, bluegill, yellow perch, and white sucker. Walleye fry are currently being stocked in Greenstone during odd years. The 2024 walleye gillnet catch rate was 3.9 fish/net, which was above average compared to other similar lakes and right at average compared to past surveys on the lake. Lengths ranged from 8 to 23 inches with an average of 17 inches which was good compared to past surveys. Growth rates were slightly better than average compared to other lakes in the area with a walleye taking 3 to 4 years to reach 14 inches long. Ages ranged from 1 to 19 with no single exceptional year classes, and walleye ages indicate that natural reproduction is occurring on a regular basis. The northern pike gillnet catch was 3.4 fish/net which was above average compared to past surveys on Greenstone. Lengths ranged from 15 to 31 inches with an average of 23 inches. Overall, the pike on Greenstone are relatively abundant and smaller in size, making it a great candidate for angler harvest of smaller individuals. Although gillnets are not intended to sample bluegill effectively, this survey did produce a bluegill catch rate of 1.9 fish/net. This catch rate was well above average compared to previous surveys on the lake. Lengths ranged from 4 to over 7 inches with an average length of about 5 inches. Rock bass, white sucker, and yellow perch were also sampled. Their catch rates and sizes were similar to past surveys.

Greenstone Lake is located 10 miles east of Ely. There are four accesses that are all remote carry-ins. Accesses consist of a 3/4 mile portage from Madden Lake, a 1/2 mile portage from the North Kawishiwi River, a winter snowmobile route to Pickerel Lake, and the trail system off the Madden Creek Rd. This 332 acre lake contains four inlets and one outlet which flows to Pickerel Lake. Greenstone Lake has a maximum depth of 72 feet and brown bog-stained water. On August 12, 2019 Greenstone was thermally stratified with a surface temperature of 71 F and a bottom temperature of 44 F. Oxygen levels were adequate for gamefish to a depth of 63 feet where the temperature was 45 F. Lake bottom substrates along the shoreline of Greenstone Lake are mostly boulder and rubble. Aquatic plants are sparse and only grow in some of the shallow bays. There are a handful of water access only cabins on the lake, overall it is quite undeveloped. The overall gillnet catch rate for all fish combined was 9.3 fish/net which was slightly below average for the lake. Yield was 13.7 lbs/net which was also just below average. Fish species sampled were walleye, northern pike, bluegill, white sucker, rock bass, yellow perch, and largemouth bass. Trap nets were used for the first time on Greenstone and caught fish at an overall rate of 11.4 fish/net, yield was 8.3 lbs/net. Fish species sampled in trap nets were mostly bluegill, northern pike, and walleye. Smaller numbers of rock bass, largemouth bass, and yellow perch were also sampled. Walleye fry are currently being stocked in Greenstone generally every third year. The 2019 walleye gillnet catch rate was 3.6 fish/net, which was above average compared to other similar lakes and right at average compared to past surveys on the lake. Lengths ranged from 9 to 24 inches with an average of 17 inches which was good compared to past surveys. Growth rates were slightly better than average compared to other lakes in the area with a walleye taking four years to reach 14 inches long. Ages ranged from 1 to 20 with no single exceptional year classes. The northern pike gillnet catch was 1.6 fish/net which was above average compared to other similar lakes but slightly below average compared to past surveys on Greenstone. The average pike weighed 4 pounds which was good compared to other similar lakes. Lengths ranged from 20 to 29 inches with an average of nearly 24 inches. Sixty-four bluegill were caught in trap nets for a catch rate of 7.1 fish/net which was very good compared to other similar lakes. Sizes were small though, ranging from 3.5 to nearly 6 inches with an average of just over 4 inches. Over 90% of the fish were under 5 inches long. This appears to be common for Greenstone as past surveys showed similar small sizes from bluegill caught in gill nets. Small numbers of largemouth bass, yellow perch, rock bass, and white sucker were also sampled. Their catch rates and sizes were similar to past surveys.

Greenstone Lake is located 10 miles east of Ely. There are four accesses that are all remote carry-ins. There is no ramp on this lake. Accesses consist of a 3/4 mile portage from Madden Lake, a 1/2 mile portage from the North Kawishiwi River, a winter snowmobile route to Pickerel Lake, and the trail system off the Madden Creek Rd. This 332 acre lake contains three inlets, all on the east side (small creeks from the north and from the east drain wetlands, and the Conchu Lake Outlet) and one major outlet, the Greenstone Lake Outlet which flows to Pickerel Lake. Greenstone Lake has a maximum depth of 72 feet and the water color at the time of this survey was light brown. On August 11, 2014 Greenstone was thermally stratified with a surface temperature of 74F and a bottom temperature of 43F. Oxygen levels were adequate to a depth of 62 feet. Lake bottom substrates along the shoreline of Greenstone Lake are mostly boulder and rubble. Aquatic plants are sparse and only grow in some of the shallow bays. There are a handful of water access only cabins on the lake, overall it is quite undeveloped. The overall gillnet catch rate for all fish combined was 10.9 fish/net which is average compared to historic surveys. Total yield was 14.5 lbs/net which is slightly below average. Fish species sampled in gill nets were walleye, northern pike, yellow perch, bluegill, white sucker, and rock bass. Walleye have been stocked as fry in Greenstone Lake dating back to 1942. Most recently, around 350,000 fry have been stocked every three years. In the 2014 survey twenty-nine walleye were sampled in gill nets for a catch rate of 3.2 fish/gill net, which is above average compared to other similar lakes. Fish captured in gill nets ranged in size from 8 to 24 inches with an average of 16 inches. Average weight per fish was 1.7 pounds which is good compared to other similar lakes. Growth based off of otolith ages appears to be somewhat slow compared to other walleye populations from lakes in the Tower Management Area. Ages ranged from 1 to 12 with only two missing year classes (2003 and 2005). When comparing stocked vs. non-stocked year class strength the stocked classes seem to be outperforming by a fairly wide margin. Interestingly the oldest year class observed (2002) was tied with two much younger year classes (2011 and 2012) for the strongest representation by a year class in the catch. The northern pike gillnet catch was 1.8 fish/net which is above average compared to other similar lakes but slightly below the lake assessment average. Average weight was 3.3 lbs/fish which is slightly better than other similar lakes. Lengths ranged from 20 to 32 inches with an average of 24 inches which is better than the historic average of 23 inches. Although bluegill are normally not assessed with gill nets, they have been captured on a fairly regular basis in Greenstone. The 2014 catch was 1.6 fish/net which is above the historic average. Sizes were small with an average of 4.5 inches although this isn't a lot different than the average historic length which is 5 inches. Fourteen yellow perch were sampled in gill nets for a catch rate of 1.6 fish/net which is above average compared to other similar lakes and past assessments. Lengths ranged from 6 to 7 inches with an average of 6.5 inches. These sizes are on par with fish from previous surveys. Cisco were sampled in only one survey (1976) but the thermal habitat of the lake appears quite suitable. We set 3 experimental gill nets deep and 3 deep water small mesh gill nets specifically targeting cisco habitat. No fish were captured in the small mesh nets and only one northern pike and one white sucker were sampled in the deep experimental sets. In addition to these nets, walleye and pike stomachs were checked for cisco remains, none were found.

Based on Minnesota DNR survey data, anglers target Northern Pike, Walleye, Largemouth Bass, Bluegill, and Yellow Perch in Greenstone. See the full species list above for catch rates, size structure, and quality scores.

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

Greenstone has a maximum depth of 72 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Greenstone is from 2024.

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