2/7/2020 10:31:00 AM Farmers need to be aware of nitrogen restrictions in fall
As of fall 2020, nitrogen fertilizer applications on farm fields will be restricted in areas of Chisago County determined to be vulnerable to groundwater contamination.
If you are curious whether this regulation applies to your property, you can type a specific address into the state Dept. of Agriculture’s website. The database is at www.mda.state.mn.us and find Vulnerable Groundwater Areas maps.
The MN Department of Agriculture wants farmers to understand upcoming nitrogen use controls are part of the Groundwater Protection Rule.
Larry Gunderson, with the MN Department of Agriculture, said the restriction is all about timing. Fertilizer containing nitrogen may be applied in spring and summer when plant growth is taking up the nutrient. Enforcement will be complaint-driven, and ag department staff will follow up on any fertilizer application in fall or times of frozen soils.
The state ag department also hopes farmers in the month of February, will take a few minutes and complete a pesticide and fertilizer use survey available on-line. The questions focus on your 2019 growing and the pesticide and fertilizer use on corn and soybeans.
Producers are not asked any personal questions, and the response is completely voluntary. But, it’s an important tool for research purposes.
According to the MN Dept. of Agriculture office, results provide guidance on education and research programs.
Producers can also call the department from 7 to 9 p.m. Monday through Saturday at 651-261-1993.
Groundwater protection rules and vulnerable areas in Minnesota are founded on types of soils and geology, Gunderson added. The vulnerable areas have shallow bedrock, coarse soils and/or karst geology.
In Chisago County the soils and conditions for contamination differ if you are on the sand plain or the river terrain or in-between.
Sunrise and Amador Township wells were part of a 2018 well testing program that helped to identify vulnerable groundwater areas. “Township” tests were done in ag territories across Minnesota with funding through the MN Water, Land & Legacy Amendment.
Test kits were distributed to 1,042 households locally, according to MDA. Only about 400 tests actually were returned for analysis, but the conclusions are that Sunrise in general, had the highest nitrate groundwater concentrations in the county. There were 262 sites with five percent or greater mg per liter. Nitrate-nitrogen shouldn’t be more than 5.4.
The “vulnerable areas” in the county, where there’s the type of soils conducive to contamination and there’s active row crop farming-- are shown in purple on the MN Dept of Ag map. Land areas where less than three percent of a county (statewide) is used as agricultural land, were not part of the “township tests.”
Funding supporting this data collecting effort comes from the Clean Water, Land and Legacy Amendment revenues.
Field Management The Chisago County Soil and Water Conservation District partnered in the water test program in 2018. SWCD has been involved in studies for years; for instance there was a comprehensive testing and data collection at Spring Creek Farm near Almelund, from fall 2010 to 2016 when the John and Jewell Peterson Farm was enrolled in the massive Discovery Farms project.
Equipment was set up to monitor off-field erosion, velocity of run-off, and contents. The information gathered over several years allowed analysis of when is it most effective to apply nutrients? Interestingly-- the months of February and March contributed 42 percent of run-off for the whole year.
When crops are actively growing, the study says, even during heavy precipitation events, less run-off was measured than other time periods.