Stand by the shore of most any Minnesota lake and you'll see something once totally absent: rocks, lots of rocks, stacked mile after shoreline mile. Ask why and the typical response is "erosion control." Landowners believe rocks prevent waves and spring ice from tearing into banks and lawns of their prized lake places.
But wait, those lakes with their waves and ice have been around for eons with shorelines pretty much as they've always been … without rocks. That's because ahead of the pell-mell rush for lakeside living there were forests of deep-rooted trees, woody shrubs and natural grasses that kept things in place.
Into the 1960s, non-metro lakes were largely forested to water's edge, with sparse development. Boy, that's changed.
Fact is, despite permit requirements, most shore rock has little to do with erosion. It's become a lake fad, with folks spending heavily lest theirs becomes the lone lot with scraggly weeds (i.e., natural vegetation), and unraked sand. They pay yet more for equipment to clear annoying weed-beds (i.e., prime fish habitat).
All those rocks on the lake are signs that lakes are, well, on the rocks — as with too many on the state's lengthy "Impaired Waters" list that grows by triple digits with each biennial update. It's not just the rocks, but all that goes with them.
Paul Radomski, lakes biologist with the state's Department of Natural Resources in Brainerd, says the shoreline-rock craze started in the 1980s and '90s as prosperity ignited a lake-living boom.
The horde of newbies brought with them a suburban landscape ethic that favored clearing the natural stuff and planting nonnative grass, manicured to the water line and lathered with phosphorus-laden fertilizers to keep lawns green — just like home. Gone are shore plants to take up nutrients before they seriously degrade the very waters that everyone loves to love.
Radomski said there are cases where newbies unwittingly caused unwanted erosion by clearing trees and stabilizing plants.
But more and more the rocks have transformed shores into a desert-like sameness. Up to 80% of some lakeshores are packed with comparably sized boulders 6 feet or more up the bank.
Walking on the sharp, often wobbly rocks invites a bad result, so they're avoided, and a popular activity of yore — beachcombing, and the exciting world of youthful discovery — is nearly extinct. Rocks also dissuade nesting loons, turtles seeking to bury eggs, or ducks seeking cover to hatch a brood. Frogs lost perches to croak into the night with chirping crickets amid the fireflies.
Once a symphony hall for nighttime critter music, shorelines have become as quiet as, well, a rock.
There are better ways to stabilize shorelines, says Jeff Forester of Minnesota Rivers and Lakes Advocates. What's always worked, he said, is planting deep-rooted ground juniper, birch and the hardy basswood along with natural plants available from most nurseries.
Forester and Radomski agree: If your lot is rock-free, keep it that way. If rocks are there, leave an unmowed buffer between the lawn and rocks; let grass grow and plug in natural plants and flowering perennials.
Nearshore soil stores a "seed bank" of natural grasses that sprout and grow on their own. The benefits are nutrient-cleansing (phosphorus levels, a key pollutant, are sharply up), discouraging geese that are wary of predators lurking in long grass, and blossoming perennials that draw butterflies and pollinators by day and might bring back those nighttime music makers.
Let "weeds" grow between rocks, and plant natural grasses by punching through the plastic barrier under the rocks. Beauty abounds while rocks continue to provide whatever "erosion control" some think is needed.
The DNR, the Rivers and Lakes Advocates, and Soil and Water Conservation Districts are working to inform lakeshore owners of the benefits of all that natural growth. Forester's "Land Stewards Project" already has active volunteers on several lakes including Vermilion, and Cass County's Roosevelt and Washburn.
Perhaps the state's most active volunteer is Nancy Moe-Mergun of Lindstrom, who doggedly led a yearslong team effort to reverse serious damage to Center Lakes — that recently were removed from Minnesota's Impaired Waters List. Laudable, but there's still 1,600 to go.
Ron Way lives in Minneapolis.