Adapt-N models the impact of different tillage methods on nitrogen availability. It simulates decomposition of incorporated vs. surface residues, and adjusts temperature and moisture conditions.

There are nine Tillage methods available for use in Adapt-N:

**Conservation tillage**: select the approximate % of the previous crop’s residue remaining on the surface after all tillage passes. Conservation tillage leaves at least 25% of the previous crop’s residue on the surface.**No-Till:**no additional input values are needed. This is modeled equivalently to Conservation Tillage with 100% residue.**Spring Tillage (only)**: Enter the approximate date of tillage and the approximate depth of tillage.**Fall Tillage (only)**: No additional input values are needed.**Fall and Spring Tillage**: No additional input values are needed.**Strip-Till/Zone-Till (Spring)**: No additional input values are needed. Adapt-N assumes a residue percentage of 75%.**Strip-Till/Zone-Till (Fall)**: No additional input values are needed. Adapt-N assumes a residue percentage of 75%.**Ridge-Till (Spring)**: No additional input values are needed. Adapt-N assumes a residue percentage of 50%.**Vertical Tillage**: No additional input vales are needed. Adapt-N assumes a residue percentage of 50%.

**Important note:** If multiple methods of tillage are used, select the option that most closely reflects the effects on crop residue incorporation.

When specifying Tillage % Residue, only a general estimate of the % residue remaining from the previous year’s crop is needed (the options in Adapt-N are 25, 50, 75, or 100%). For guidance on estimating this value, you can use the percent surface residue values detailed in the following Purdue University fact sheet: https://www.extension.purdue.