QUESTION:

Why are nutrient management plans important for land application?

ANSWER:

I am frequently asked why nutrient and crop management plans are important if a pumper is going to use land application as a part of a septage treatment program. In the past I have explained what goes into a nutrient management plan, and that the federal rules regarding land application focus on the maximum allowable nitrogen application rate. Nutrient management plans are important for two reasons: to maximize the crop yield and protect the environment.

Whether you as a pumper are land-applying on your own property or working with a nearby farmer, it is critical to understand the nutrient needs of the crop being grown on the fields from an economic standpoint. If you are renting the land or working with a farmer, it is important that the crop yields enough to provide a return on the investment to either pay the rent or provide the farmer with income. If it is your own land then you still want a return over and above what you are receiving through pumping fees.

As I wrote in previous columns, the maximum allowable nitrogen application rate often does not supply the amount of nitrogen needed for high-value crops such as corn. The farmer will need to supplement the septage with additional applications to ensure an adequate yield. This is why a yield goal based on the crop, soil and environmental conditions at that location is established and it drives the application rate.

Other important factors can serve as a basis for future columns, such as the timing of applications of septage or otherwise, the total overall rate, the crop rotation and the source of additional applications. The bottom line is matching the crop needs to the applications to receive a realistic and adequate crop yield.

NITROGEN WATCH

From an environmental perspective, several concerns are related to the nutrients in septage, manure or commercial fertilizers. Excessive nitrogen applications can lead to nitrogen leaching through the soil to the groundwater or running off into surface waters. This can affect drinking water supplies. I recently read an article about the City of Des Moines, Iowa, which is suing adjacent counties due to runoff from agricultural lands resulting in elevated levels of nitrates in the water they pull from the Des Moines River for a drinking supply.

In addition, here in the Midwest we worry about the level of nitrate-nitrogen in the Mississippi River, which contributes to hypoxia in the Gulf of Mexico. On the East Coast, there is concern for the impact of nitrogen on estuaries and Chesapeake Bay algal blooms. These are all large environmental problems with economic impacts.

Even though septage rules focus on nitrogen as the nutrient of environmental concern, another nutrient of concern is phosphorus. As a colleague often points out to me: Take a look at manure management issues and you will see where septage land application concerns will be also.

The concern over phosphorus and its contribution to excessive algal blooms in freshwater systems was highlighted in the summer of 2014 by a harmful algal bloom in Lake Erie. Toxins created by the algae affected the drinking water supply for the City of Toledo, Ohio. This led to calls to reduce phosphorus loads by 37 percent in the Maumee River watershed. Requirements such as this will reduce the allowable level of phosphorus applied to cropland, regardless of source.

Ohio has also enacted legislation requiring certification for nutrient applicators that work 50 or more acres. This raises the need for pumpers who land-apply to follow a nutrient management plan that looks at all the crop nutrient needs as a part of the operation. It is another way to demonstrate that land application is a viable and economic alternative that also helps protect the environment.

ASK FOR ADVICE

If you or the farmer you work with are not working with a crop adviser who provides a nutrient management plan, there are ways to get assistance with the plans. A good place to start is your local County Extension office; they can provide information on the current University crop nutrient recommendations for your state and location. These recommendations are the foundation for developing a nutrient management plan.

A visit to the local National Resources Conservation Service (NRCS) office can make you aware of potential cost-sharing opportunities available through the NRCS EQIP program to provide nutrient management planning through recognized crop professionals called Technical Service Providers who are certified to write the plans.

Having and following a nutrient management plan ensures you are using and in compliance with the current requirements. Remember that within the 503 regulations there are the separate reporting requirements for tracking and documenting your application rates. These need to be followed and adhered to, and you need to be able to present your plan and documentation upon request.

Finally, when you have and follow a nutrient management plan, you can be confident that you are maintaining the best practices available to provide an economic return on your investment and do the best you can to protect and enhance the environment.