Buffer alternatives: Finding the right conservation ‘fit’ for each farm

Minnesota’s buffer law was created to protect state water resources from erosion and runoff pollution. While Minnesota farmers agree with the intended outcomes of the buffer law, many are concerned that what is proscribed in the legislation will not achieve the intended results.

That’s why the law was also written to give farmers and landowners ‘alternatives’ in cases where the vegetative buffer won’t work or where there might be an even better way to achieve the same water quality benefit.

But what are those alternatives? Are they all effective? And what happens when various practices like cover cropping, reduced tillage or saturated buffers are used in combination?

The grower leaders at Minnesota Corn Research and Promotion Council (MCR&PC) and Minnesota Corn Growers Association (MCGA) saw an opportunity to fund research answering these questions.

A conversation with leaders at Minnesota Board of Water and Soil Resources (BWSR), which has been given the task of putting the buffer law into effect as of Nov. 1, 2017, has led to a partnership between Minnesota Corn, the University of Minnesota (UMN) and BWSR.

With support from Minnesota’s corn organizations, researchers at the University of Minnesota are working to identify a matrix of ‘alternative’ best management practices for water quality. UMN is collaborating with BWSR on this project to ensure that these identified practices will, not only help water quality, but will also be accepted alternatives under the buffer law.

“This is a working-together endeavor,” says John Jaschke, executive director of BWSR. “That’s important for all the aspects of making this buffer initiative work. The practical part of this is what we are most interested in, and what I think the farmers are most interested in—to come up with some options for circumstances on a producer’s land, where a buffer strip, or filter strip as it is often called, may not be the one that will do the most good. We are looking for ways for people to look at the alternatives and find the one that may work better than or instead of the buffer of the prescribed dimensions set out in the law.”

According to Jaschke, based on preliminary assessments, approximately 80 percent of the land in question is already in compliance with the buffer law. An inventory conducted by local Soil and Water Conservation Districts (SWCD) points to lands along designated waters where buffers or buffer alternatives are needed.

Professor Dave Mulla, a soil scientist, and Professor Chris Lenhart, a water resources scientist, are leading the research project at the University of Minnesota.

“We are going to do a literature review of the effectiveness of best management practices, and then we are going to do some evaluation of a few types of practices using water quality models, to evaluate what is the impact of the vegetative buffers in terms of their water quality benefit, and then what is the effectiveness of these different alternatives,” says Mulla, a faculty member of the UMN Department of Soil, Water and Climate. “The modeling will help us determine which practices could supplement a narrower buffer, or which ones could replace the buffer.”

The co-investigator, Lenhart, is a faculty member of the UMN Department of Bio-Products and Bio-Systems Engineering. Together, Mulla and Lenhart have assembled a team of eight researchers with expertise in nutrient loss reduction in agricultural systems.

“They are currently reviewing literature,” says Paul Meints, MCGA research director. “There are existing practices where we already have the scientific research showing they work as alternatives to a buffer. We know that individual practices have an impact, but what we haven’t done is to look at the summation of those practices and how they work together.”

The final outcome of this research project would be a decision matrix of alternative practices that farmers could use to build upon and improve their current conservation efforts. Farmers would then be able to work with their local SWCD to develop a more specific design of how these practices could actually be implemented.

“Ultimately, we are going to develop a simple decision tool, based on the literature and on the modeling, that can be used to help farmers identify which practices could be used as alternatives,” says Mulla. “This decision tool will start out by asking some simple questions…what is the existing management system, what type of tillage is used? Is there any cover cropping? What is the crop rotation? Then we will ask about the soil, is it sandy, is it clay? Is the slope flat or steep? Ultimately, we will be able to provide a series of suggestions for alternative practices and their combinations that could be used to give you water quality protection.”

For more information on research projects funded by Minnesota’s corn farmers, click here.

Meghan Doyle