IAMP-Conservation Crop Rotation Practice (NRCS Code 328)

Description

Establish a Resource Conserving Crop Rotation. Rotation must include at least one resource conserving crop as determined for Idaho in a minimum three-year crop rotation. The crop rotation is designed to either increase soil carbon and/or reduce greenhouse gas emissions. The practice may reduce soil erosion (water and wind), improve soil health, improve soil moisture efficiency, and reduce plant pest pressures. See NRCS Conservation Crop Rotation (328) and Idaho E328A criteria for rotations as references.

Benefits

Improves soil health and organic matter; reduces weed, disease, and pest pressure; improves filtration and soil moisture efficiency; improves soil aggregation depending on specific rotation.

Soil Carbon Impacts

Depending upon the specific rotation sequence, carbon incorporation could improve from incorporated residues. The permanence of the increased soil carbon depends on the rotational sequence and specific crops.

Greenhouse Gas (GHG) Impacts

Reduced use of herbicides and fertilizers can reduce associated GHG emissions from manufacturing these products. Depending upon type and amount of carbon, CO₂ production could increase as microbial driven decomposition of labile forms of carbon leads to increased respiration. If N fertilization is reduced overall in the rotation (e.g. conversion from a N-demanding crop to a legume), N₂O emissions could be reduced.

Considerations for Success

Choose a crop rotation system that considers the following: meets goals, matches labor availability, breaks pest cycles, and minimizes soil erosion. Prioritize benefits that are the most meaningful for your operation and plan accordingly.
Maintain flexibility when planning a crop rotation with novel crops and be ready to adapt to unexpected challenges.
Consider crops that best match your soil’s potential, don’t require unnecessarily high input costs and are compatible with other cash crops in your rotation.
Tillage management should be considered in combination with crop rotation to maximize additionality of soil carbon.
In arid regions, if one of the crops replaces fallow, water availability could be reduced overall.
Herbicide carryover. Growers need to be careful based on labels.
The additional costs to the growers include:
- Seed costs,
- Fuel costs,
- Labor,
- Possible fertilizer costs,
- Possible equipment costs, and
- Marketing the novel crop could present challenges.

IAMP Preferences/Considerations

The IAMP project incentivizes practices that result in a net reduction in GHG and increase in soil carbon. To make a permanent impact on GHG reduction and increased soil carbon, one or more rotational crops should have a high C/N ratio, maximize total biomass, plant early/harvest late (e.g. winter cover crops preferable), high nitrate uptake/conversion to biomass, in 1 out of three years. COMET-Farm simulation of the rotational plan should indicate a minimum of 0.2 Tonne CO₂eq/ac decrease in GHG. Cover crops may be included within the rotation, which could be considered stacking depending on the rotation (see “Stacking” below).
Fields are eligible for incentive only if a new crop is added to the rotation on that field. Crops may not have been planted in the last five years.

Criteria/Verification

Crops shall be grown in a planned sequence as outlined in the IAMP contract.
Certificate from seed suppliers and any additional evidence (e.g. as-applied seed map) that the crops were planted and harvested as outlined in the IAMP contract.
Photo of each crop in rotation six weeks after planting.
COMET-Farm simulation of the rotational plan should indicate a minimum of 0.2 Tonne CO₂eq/ac decrease in GHG.

Incentive Payments

$38/acre/year in the year(s) with an additional crop to the baseline rotation.

Stacking or Companion Practices

Conservation cropping rotations are compatible with other incentive IAMP practices implemented in the novel crop year or other years of the rotation including cover cropping, reduced N applications, partial fertilization with manure, reduced or no-till, and grazing. Stacking is encouraged. Variations and creativity are encouraged with an eye to maximizing GHG reductions. If stacking with cover crop practice, must include at least one additional crop in a three-year rotation.