Skyrocketing commercial fertilizer prices have changed that. Today, greater emphasis is placed on the cost and accuracy of manure application. Following are five tips to help ensure you get the most value from the manure you supply or apply.

Sample and test annually.

Manure from each storage facility must be sampled and tested to ensure that applied nutrients match soil needs. Laboratory analysis should provide the following basic information: dry matter (DM) or moisture content; ammonium nitrogen (NH₄N); total nitrogen or total Kjeldahl nitrogen (TKN); phosphorus (P₂O₅); Potassium (K₂O) plus pH; electrical conductivity; and chlorides for lagoons.

Ideally, samples should be tested before nutrients are applied. However, manure must be agitated before sampling, and many hog producers are reluctant to pay energy costs to agitate manure before they are ready to apply it. In those situations, samples are gathered as manure is applied, test results are recorded annually for each facility and application rates are based on the historical nutrient levels.

Dave Hartke, a custom applicator and pork producer in Effingham, IL, says this approach works fine because manure tests don't vary much from year to year if feed, pig genetics and facilities remain essentially the same.

“I've got manure tests for 10 years on my own farm and they haven't varied very much,” Hartke says, although a recent conversion from farrow-to-finish to a wean-to-finish operation will have some impact.

Keep in mind that dilution from water line leaks or other events can alter test results.

Agitate before you test.

Liquid manure must be agitated because nutrients settle unevenly during storage. Nitrogen (N) and potassium (K) tend to remain well distributed, but phosphorus (P) settles.

According to the Midwest Plan Service document MWPS-18 Section 1, phosphorus tests can vary 300% or more from top to bottom if probe samples are taken without first agitating the storage facility (see www.mwps.org for manure management publications).

The best shot at getting a representative sample is when the pit or lagoon contents are agitated continuously during pumping and samples are taken from the flow of manure being drawn from the storage unit, says Ted Funk, extension specialist at the University of Illinois. With lagoons, a representative sample may require multiple agitators, operating simultaneously, to get the job done.

Remember, extreme caution must be observed during agitation of below-ground tanks, pits and transfer stations because gases released from agitated liquid manure can be deadly. People must stay out of buildings and it's best to remove animals prior to agitation; buildings should be well-ventilated and any animals remaining in the buildings should be carefully observed for signs of stress as agitation is begun.

Keep good records.

Keeping close track of manure management activities is important to ensure you are using manure effectively and staying on track with nutrient management plans, says Funk.

“It is hard for producers to find time to go back and do updates on their plan, but it is important to calculate what was actually applied,” Funk says.

Brian Henze, who coordinates precision farming services at the Effingham-Clay FS Service Company in Effingham, IL, emphasizes the importance of good accountability for every gallon of manure applied. “If you are spreading commercial fertilizer, you know what you put where, and you have to do the same with manure,” he says. “That's the way you are going to get the most bang from the buck.”

Enlist technology.

One solution for keeping accurate, detailed manure application records is to create “as-applied” maps using Global Positioning System (GPS) and flow meters. Speed and flow (gal./min.) are combined to calculate how many gal./acre were applied at various points in the field.

GPS mapping is especially helpful when problems arise. “GPS provides something you can show the regulating agency that might be interested in seeing whether you are sticking to your plan,” says Funk.

GPS technology also improves application accuracy. The “tattletale” account shows where the application equipment has been and, if application is interrupted, the point where it was stopped.

“It's nice to know precisely where you left off when you come back to apply again,” he says. “Or, if you ran out of manure and you wanted to finish off with commercial fertilizer, you could easily see where the track was and come back and pick up from there.”

GPS coordinates can also be used to create “no fly zone” maps to avoid application in specific areas, Funk says. “You can put a map together that shows surface water, streams, wellheads or other things to avoid. Then, you can draw in the targets that you can watch on your GPS display to avoid those setback areas.”