The following AMTs have been approved and are considered an alternative to specific nitrogen fertilizer best management practices (BMPs). The complete list of BMPs and approved AMT substitutions is currently under development and will be available on the AMT substitutions for BMPs page.
Alternative cropping systems, low nitrogen input crops, or continuous cover
The Increasing Continuous Cover: Cover Crop AMT (PDF) includes continuous vegetative cover practices that have well documented reductions for nitrate leaching. Specifically, they can reduce or eliminate nitrogen input needs and /or increase overall uptake of nitrogen making it less available for leaching. This reduces the inherent risk of nitrogen loss.
Increasing Continuous Cover: Perennial Vegetation AMT (PDF) describes an option for crops or vegetation that grow three growing seasons or longer. Examples of perennial vegetation in Minnesota are alfalfa, pasture or hay with perennial grasses, clovers or other forbs, intermediate wheatgrass, silvopasture, bioenergy crops such as switchgrass and miscanthus, and shrub or tree crops such as poplar and hazelnuts.
Retiring Cropland: Land Conservation (Set Aside) Programs AMT (PDF) includes a variety of federal and state programs that have converted cropland and other agricultural land to natural vegetation, wildlife habitat, or wetlands. The following programs have been reviewed and are included as AMTs:
- Conservation Reserve Program (CRP)
- Conservation Reserve Enhancement Program (CREP)
- Reinvest in Minnesota Program (RIM) (conservation and wellhead protection easements)
- Other minor (i.e., limited acres) federal and state set aside programs are also listed, see the full document for more information.
Intermediate Wheatgrass (Kernza) AMT (PDF) describes the option of growing intermediate wheatgrass for groundwater protection. Intermediate wheatgrass is a perennial deep-rooted grass that has been domesticated as a grain crop.
Advanced nitrogen fertilizer management
On-Farm Nitrogen Rate Trials AMT (PDF): The intent of the on-farm nitrogen (N) rate trial AMT is to align N application rate(s) to the needs of the crop while at the same time optimizing the profitability and minimizing N loss to the environment. This AMT includes options for on-farm nitrogen trials as an adaptive N management strategy to justify rate exceedances above the N fertilizer rate identified for a Level 2 Drinking Water Supply Management Area (DWSMA).
Precision agriculture
Precision Agriculture AMT (PDF) includes two precision nitrogen management options for applying N fertilizer above the MDA published rate for the DWSMA.
- Basic Variable Rate Nitrogen
- Utilizing Advance Technology for In-Season Nitrogen Management
