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.