Code of Practice for Nitrogen Fertilization
ACWA 2021

Download the 2021 Code of Practice

Purpose: To establish and implement reasonable and practical guidelines for nitrogen fertilization applications to reduce nitrate loss from farm fields.

Why: Effective management of nutrients on farms is one of the keys to enhancing both environmental quality and profitable crop production. Consistent with the Iowa Nutrient Reduction Strategy, this Code of Practice provides information about guidelines adopted by the ACWA members as a condition of membership.

Application Guidelines

  1. A nutrient budget for nitrogen, phosphorus and potassium shall be developed that considers all potential sources of nutrients including manure, legumes, etc. Nutrient recommendations shall be based on current soil test results, realistic yield goals, environmental impact, and producer management capabilities.
  2. Use the standard county temperature and forecast maps found at http://extension.agron.iastate.edu/NPKnowledge/ as part of the decision-making process for fall fertilizer application.
  3. Delay fall anhydrous applications without a nitrification inhibitor until soil temperatures are 50o F, trending lower.
  4. Use On-line ACWA Self-Reporting System to document conformance with requirement:
    • Regular ACWA Board Member assigns staff responsibility to report start of application for all counties within member trade area.
    • Self-reporting system is on-line at: ACWA Self Recording Form (a specific username and password has been assigned for each member organization). Simple, easy, takes less than 1-minute to complete on computer, cell phone, or other electronic devices.
    • Any questions contact: Roger Wolf, ACWA Executive Director, roger@acwaiowa.com, 515-205-9225 or Kristen Dearden, ACWA Membership Services & Outreach Manager, kristen@acwaiowa.com, 515-334-1482.
  5. Regardless of time of year application occurs, encourage use of other supporting nutrient management technologies such as stabilizers, slow-release fertilizers, incorporation or injection, soil nitrate testing and other technologies that minimize loss to surface or ground water resources.
  6. If producer is participating with USDA Conservation Programs additional considerations for producer conformance with NRCS 590 Nutrient Management standard shall be followed. For guidance and requirements see standard: Iowa Nutrient Management Conservation Practices Standard Fact Sheet, https://efotg.sc.egov.usda.gov/references/public/IA/Nutrient_Management_590_STD_2013_10.pdf
  7. Encourage use of other supporting water quality practices where feasible:
    • Tile line denitrification bioreactor
    • Constructed wetland
    • Conservation stream buffer and/or saturated buffer strips
    • Fall cover cropping system