Summer 2008

P-Index Manure Management Plans - The Final Push

PRINT VERSION (pdf) Download the Summer 2008 issue of Iowa Manure Matters - Odor and Nutrient Management Newsletter in pdf format.

By Angela Rieck-Hinz, Department of Agronomy, Iowa State University

soil samplingSenate File 2292, passed by the Iowa Legislature in the spring of 2002, set forth requirements for producers to meet the Phosphorus Index (P-Index) manure management plan requirements if they had more than 500 animal units in confinement. That law also provided a phased implementation schedule for adoption of the P-Index manure management plans. We have now reached the final phase-in period for implementation of the P-Index plans.

Beginning on August 25, 2008, those producers who filed their original manure management plans with the Department of Natural Resources (DNR) prior to April 1, 2002, will need to file their P-Index manure management plan with DNR when their annual update is due. The DNR estimates that nearly 2,500 plans will need to convert to the P-Index sometime between August 25, 2008 and August 2009. We estimate this will be the largest number of plans to make the conversion in a 12-month time frame since the rules were implemented.

What does this mean to you?

If you are a livestock producer with more than 500 animal units in confinement and your P-Index plan will be coming due, here are the things you should be considering in preparation of your impending deadline.

  1. Know when your P-Index plan is due. The DNR will send you a letter 45 days in advance of when your plan is due.  Don’t wait until you receive this letter to begin planning for your P-Index plan.
  2. With the wet fall last year and the wet spring this year, getting soil sampling done has been challenging. The P-Index requires you to meet minimum soil sampling requirements for existing facilities and the samples must be less than 4 years old. You are required to have these soil samples by the time your plan is due. Take soil samples now for plans due this fall, or plan to sample this fall for plans due this winter and next spring. You can take your own soil samples, but if you plan on having your local co-op or service provider take the samples - get on their schedule now.  Make sure they know what is required.  For more information on soil sampling requirements see this previous newsletter article (Spring 2006, EDC-129-30, Volume 9, Issue 1) “Sample soil and plan now for fall manure management that includes the P index”.
  3. Have as much data available as possible prior to beginning the development of your P-Index plan. Because the use of the Iowa Phosphorus Index calculator also requires the use of the Revised Universal Soil Loss Equation 2 (RUSLE2) software, there are many pieces of data such as crop rotations, tillage practices, slope length and slope percent, residue amounts, manure applications, and conservation practices that are needed. A data collection worksheet is available to help you determine what is needed and where to find the needed information.  Please see Iowa State University Extension fact sheet PM 2021 “Data Collection Worksheet for RUSLE2 and the Iowa Phosphorus Index” available at:
  4. soil samplingIf you plan to hire a consultant, contact them now, don’t wait. Many of the consultants who are preparing P-Index plans tell us they are busy and it is difficult for them to take on new clients. A link to a list of consultants who develop manure management plans is available in the resource list on this page.   In addition to the soil sample requirements, there are many pieces of data that must be collected to implement the P-Index software.  The process for completing this requirement can be lengthy depending on how many fields receive manure, if you are distributing manure through manure agreements, and the amount of required information you have on hand. For additional information about hiring a consultant, please see this previous newsletter article (Spring 2007, EDC-129-35, Volume 10, Issue 1) “Your Phosphorus Index Manure Management Plan
  5. If you are distributing manure from your facility to the neighbors through a manure easement or agreement, the fields receiving that manure, while owned or managed by someone else, will still need to be part of your manure management plan and will still require having the P-Index calculated on those fields. Plan in advance to work with your neighbors to get the necessary information to implement the P-Index.

The message of this article is clear, if your P-Index plan is due sometime in the next 12-13 months, don’t delay in developing the requirements of your P-Index plan.

Manure and Nutrient Management Plan Resources

Manure Management Plan Consultants:

Iowa P Index Calculator

The Iowa Phosphorus Index and Manure Management Plans for Confinements

IDNR Forms for Manure and Nutrient Management Plans

Data Collection Worksheet for RUSLE2 and Iowa Phosphorus Index


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