Ever since Thomas Jefferson’s Public Land Survey reached the Midwest in the 1850s, the tallgrass prairie has been plowed under, drained, and planted to row crops. Barely one percent of this original ecosystem remains.
“States like Illinois and Iowa have lost virtually all of their native tallgrass prairie,” says Steve Chaplin of the Nature Conservancy. “Minnesota still has about two percent, and it’s concentrated.” That concentration of native prairie (something Chaplin and TNC define as never having been plowed) didn’t occur through some forward thinking plan. That land was hard to farm: rocky, shallow, or extremely wet soils.
Chaplin hopes to build on those remnants with a forward thinking plan. He is an ecologist and the lead author of the Minnesota Prairie Conservation Plan, an ambitious goal to preserve and restore more than 3.1 million acres of grasslands in the state. The Plan was recently adopted by Minnesota’s Department of Natural Resources, the United States Fish and Wildlife Service, and ten conservation groups.
The Plan seeks to preserve and restore grassland—a catch-all term that includes native prairie, restored prairie, and land used for grass-based agriculture, primarily grazing (actually a critical aspect of prairie ecology) and haying (cutting of perennials for animal feed). “If we’re going to be successful in this Plan,” says Chaplin, “we have to figure out ways for people who use grassland and prairie to get a higher net return from grass-based agriculture than they can from marginal row crops.
The Plan would do this with four tiers of conservation. The most important is the network of “prairie core areas,” 36 blobs scattered across the state and ranging from 5000 to 300,000 acres. The core areas were selected for their high prevalence of existing grassland agriculture or native prairie. Within the core areas, the Plan envisions 40 percent of the land as grassland and 20 percent as wetlands, with the remaining 40 percent staying as is (mainly intensive cropland). Those numbers come from the Minnesota Duck Plan, which previously determined these optimal ratios for ducks and a wide variety of other prairie animals and plants.
The Plan connects the core areas with long “prairie corridors” each about six miles wide. Within the corridors, ten percent of each Public Land Survey section would be preserved as or returned to grassland. Within the corridors, “corridor complexes” would provide stepping-stones for species moving along the corridors from one core area to another. The complexes would constitute about 2000 acres of grassland each, and would be spaced roughly six miles apart. They would have the same 40/20 ratio as the core areas. The Plan identifies 36 of these, many of them built around existing preserved public land. Lastly, 10 percent of each unique ecological niche outside the cores, corridors, and complexes would also be preserved.
Minnesota expects to fund the Plan with more than a billion dollars from a 2008 Constitutional amendment that created a statewide sales tax dedicated to the environment and the arts (the total cost of the plan is about $3.5 billion). That amendment, in fact, was the impetus for creating the plan. But another issue makes immediate action critical. About 1.8 million acres of Minnesota farmland are set aside in the Conservation Reserve Program, a federal initiative in which farmers are paid not to farm marginal land. Many existing contracts are due to expire. With the high price of corn, farmers may take another look at wet or stony ground and return a decade or more of grassland development to row crops. Though it is not likely all this reverting conservation land can be saved, the Prairie Plan will help agencies and nonprofits prioritize easements and outright purchases, in the context of creating a cohesive network of grasslands in the state.
Minnesota will never again be covered by endless prairie. Instead, the Prairie Conservation Plan will create a web of interconnected grasslands—a web that can be home to plants, animals, and people.
Download the full plan here.
Landscape Architecture, November 2012
(note: this version is an expanded form of the one published in Landscape Architercture)