The Iowa Environmental Protection Commission is scheduled to hold its next meeting October 16 in Des Moines. A key topic on the agenda is a discussion of whether or not the state should ban application of liquid manure on land scheduled to be planted to soybeans as the next crop.
The EPC is a panel of nine citizens who provide policy oversight on Iowa's environmental protection efforts. The commission helps set rules and regulations to carry out Iowa's environmental laws. The EPC is part of the Iowa Department of Natural Resources and provides recommendations and advice to the DNR, the agency in charge of enforcing Iowa's environmental regulations.
The rule to ban manure on soybean ground was passed in 2008
The EPC established limits on manure applications in March 2008 for Iowa farmers who raise enough livestock to require them to have a state-approved manure management plan. The limits restrict the applications to 100 pounds of nitrogen on land that is scheduled to be planted to soybeans the next year.
In developing its 2008 rule, EPC determined that all applications of manure on soybean ground would be prohibited after 5 years, or as of May 14, 2013, but not until the commission takes action to review the latest science and research and affirmatively decides to put the ban into effect.
"A few months ago the DNR invited various interested parties to submit any research on this subject," explains Bill Ehm, administrator of DNR's Environmental Services Division. "The EPC must review the research and decide whether to take the steps necessary to implement the ban or not. The EPC could also decide now or at a later time to take alternative action."
Environmental and activist groups are pressuring EPC to enact the ban
Members of Iowa Citizens for Community Improvement and other activist environmental groups are pressuring EPC to put the ban into effect. Several ICCI members spoke in favor of the ban at EPC's monthly meeting in September. ICCI claims the applications aren't necessary and are detrimental to the state's water quality. Their reasoning is soybeans are a legume crop which makes its own nitrogen from the air; thus, applying manure on land that's going to soybeans isn't needed.
At the October 16 meeting, farmers and agricultural leaders will urge the EPC to consider ongoing agronomic research when it discusses the potential ban on applications of manure to land that is to be planted to soybeans.
Research results will be presented showing agronomic and environmental advantages of manure application
The research was conducted by Iowa State University. To sum it up, the studies show soybeans can use essential manure nutrients—nitrogen (N), phosphorus (P) and potassium (K)—from liquid manure. The research also shows that allowing limited manure applications will help reduce the need for tillage on highly-erodible fields. And it shows allowing manure to be applied on fields to be planted to soybeans helps reduce over-application of manure on corn-on-corn ground and helps farmers avoid being locked into planting corn-on-corn.
"It will be very important that the EPC considers the research, which clearly shows the problems with imposing a ban," says Christina Gruenhagen, government relations counsel for Iowa Farm Bureau. "While few farmers apply manure on soybean ground every year, it's important that farmers continue to have the option to apply it on land to be planted to soybeans if they get in a situation where they need to do it."
The ISU research shows giving farmers the option to apply a restricted amount of liquid manure is better for crops and for the environment. "The studies clearly show benefits from manure applications to fields going to soybeans that are short on N, P or K that can be supplied by manure," says John Lawrence, associate dean of ISU's College of Agriculture & Life Sciences.
Giving farmers the option to apply is better for crops and environment
The field research led by ISU Extension soil fertility specialist John Sawyer shows soybean plants typically do not fix all of the nitrogen they need from the atmosphere and can use manure to meet their additional needs. The studies also show liquid manure applications supply phosphorus and potassium which benefit soybean plants.
Other ISU research, involving ag engineer Matt Helmers, shows it's important for farmers to apply the proper rate of liquid manure on land to be planted to soybeans, according to the ability of the plants to use the nutrients. "If you over-apply you can end up with nutrients in the tile lines," he notes.
Actually, a ban on manure application to land going to soybeans could aggravate environmental problems in some cases, says Lawrence. It could force farmers to do tillage and plant highly erodible land so they have enough corn acres to use the manure nutrients their livestock operation produces. In addition, without the option to apply manure on land that's to be planted to soybeans, some farmers could be forced to over-apply manure on land going to corn. That could cause water quality issues.
Banning manure applications on fields scheduled to be planted to soybeans could lock farmers into a corn-on-corn cropping sequence, even though a rotation of corn with soybeans would have agronomic advantages. "Farmers would lose flexibility if there is a ban," sums up Lawrence.
Several groups will urge EPC to enact the ban on manure on soybeans
In addition to Farm Bureau and other farmer representatives, ICCI and several environmental activist groups intend to show up at the EPC meeting. ICCI will urge EPC to enact the ban on manure on land to be planted to beans. Currently on its website, ICCI says in a message addressed to its members:
* "The Environmental Protection Commission will vote on the application of liquid manure on bean ground. This is a follow up to long five year fight you've played a lead role in. And, we know from past experience that the DNR only acts when they are pressured to do so by dedicated people like you."
* "At the EPC meeting two weeks ago, we heard Iowa DNR staff tell commissioners they have three choices in regard to liquid manure on beans at EPC's October 16 meeting: 1) to ban the practice; 2) to allow it to continue; or 3) figure out some other action to take. If they take no action, the ban will automatically go into effect. Banning liquid manure on soybeans is an important, common sense step in cleaning up our water ways. The practice doesn't make sense environmentally, agronomically or economically."
* "At stake is whether our Iowa Department of Natural Resources will enact policies and rules that work to protect Iowans and our environment, or that work to protect corporate ag's bottom line."