By Shawn Perich
State officials are concerned that the rapid conversion of forest to farmland in west-central Minnesota will have lasting impacts on water quality, and fish and wildlife habitat. Potlatch, which owns hundreds of thousands of acres of commercial forest land throughout northern Minnesota, is selling some of its holdings to RDO Farms, which is clearing the woods to farm potatoes with center-pivot irrigation. Officials say thousands of acres have already transitioned from trees to potatoes. Thousands more are likely to be converted in the near future.
At the regular bimonthly meeting of the Minnesota Forest Resources Council last week, (full disclosure—I am a member of the council) Mark Carlstrom, DNR Park Rapids area forest manager, Pete Jacobson, DNR Fisheries research supervisor and Rebecca Flood, MPCA assistant commissioner, gave a presentation about the implications to water quality of converting forest land to potato fields. The area in question is part of the Crow Wing River watershed, a primary tributary to the upper Mississippi River. The water table is close to the surface and, due to sandy soils, is susceptible to contamination from agricultural fertilizers and pesticides.
Until now, the land has mostly been used to grow jackpine, aspen and other trees harvested for forest products, and for hunting deer and grouse. But the sandy uplands are also great for producing potatoes, which are grown the first year after conversion, followed in annual rotation by row crops such as corn and soybeans. Potatoes will be grown every fourth year. Most of the potatoes will be sold to McDonalds for French fries.
A combination of circumstances came together to make farming feasible here. About a decade ago, Potlatch began leasing hunting rights on its properties, which previously were open to public hunting. Then the company started selling off its forest lands, in part due to changes in forest tax laws that do not effectively encourage long-term corporate forest management. At the same time, rising commodities prices and federal agricultural subsidies made purchasing and converting the lands to farming viable. The development of new short-season varieties of corn and soybeans helped, too.
The conversion from forest to farmland happens quickly, often within just a few weeks. Last winter, over 7,000 acres were converted to agricultural use. The sale and purchase of lands between private parties is a legal transaction. It is also legal to convert the land use from forestry to farming. Center pivot irrigation is permitted by the DNR. And agriculture is a sturdy leg in the west-central Minnesota economy. Then again, so are forestry and recreation.
The issue is that agriculture has different land use effects than forestry or recreation. Farming requires fertilizers, pesticides and irrigation, all of which have the potential to diminish water quality. In contrast, the only chemical treatment managed forests may require is a minimal use of pesticides. Forests retain and filter runoff, maintaining water quality. Forests provide wildlife habitat, too.
Water quality is important to recreation. Minnesota’s best fishing lakes are located in the forested region. Lakeside development of homes and cabins is more likely to occur and have greater value on lakes with clear water rather than where the water is cloudy with algal growth spurred by agricultural runoff. Drawing water from irrigation can disrupt the inflows to lakes, streams and wetlands, and thus diminish fish and wildlife habitat.
Currently, most of the conversion is happening in Cass, Hubbard, Becker and Wadena counties. Officials are concerned that it may progress eastward into the lakes region of north-central Minnesota if suitable corporate forest lands come up for sale. Right now, the state doesn’t have a strategy to address the expansion of agriculture into the woods. It isn’t feasible to purchase all of the lands where conversion may put water quality at risk. However, county boards have passed resolutions supporting purchasing land to retain forest cover. Potlatch has agreed to hold some key parcels for the state to purchase—the DNR’s top priority is to protect access to public lands. Some Legacy Amendment funding is available for purchasing lands, though more is likely needed.
The MPCA is studying the effects of agricultural conversion on water quality at a 160-acre site owned by RDO Farms in Byron Township, 12 miles north of Staples in Cass County. The intent is to study the amount of nitrate-nitrogen loss that is occurring below an agricultural field recently converted from forest to irrigated row crop production. At the same site, the DNR is monitoring the possible effects of pumping irrigation water on nearby Tower Creek, a designated trout stream.
While the information learned from this study will be useful and allow the MPCA to develop action plans to address related water quality issues. The only problem, as one council member pointed out, is that the state has been developing plans to improve water quality for years, but hasn’t provided funding to actually implement them. Another concern expressed by others in the room is that most of the Legacy funding for clean water has been targeted for impaired watersheds in the agricultural region. Far less emphasis has been placed on protecting and maintaining excellent water quality in the forest region.
A better tax policy for forest lands, perhaps coupled with more demand for forest products, might slow the rate of conversion. But one council member pointed out that it is difficult for forestry to compete with subsidized agriculture. Another option would be for the DNR to slow down the issuance of irrigation permits until researchers evaluate the effect irrigation is having on groundwater.
At the very least, the state’s conservation community needs to become fully engaged in the land conversion issue to give state officials the support they need to protect water quality and, where feasible, acquire Potlatch lands necessary to assure access to existing public lands or protect sensitive wetlands and waterways.