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.”
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.”
Hartke relies on GPS, Krohne flow meters and Raven 660 rate controllers to help him and his two employees apply manure evenly across a field. Once a desired per-acre application rate is set — based on manure test, soil profile and cropping plans — Hartke and his operators monitor the flow rate to adjust the tractor speed of the drag-line system.
“We start off emptying a building at a rate of 1,000 gal./min. As we get farther down in the pit, it starts to suck air and flow goes down to 700 gal./min. If you stay at the same speed, it will show you are putting on fewer gallons per acre,” Hartke says. “You've got to back the throttle off or shift down in order to achieve the desired application rate.”
Although Hartke's application equipment is equipped for variable rate technology (VRT) to adjust rates based on soil and yield maps, he says most clients are not willing to pay the extra cost to make the maps. However, he believes if regulated soil phosphorus levels would become more stringent or if manure value increases further, interest in VRT would also increase. He uses VRT on his own ground and relies on Henze to create maps.
Funk says investing in VRT for manure application today is questionable, given liquid manure's dynamic nutrient profile compared to a single-component commercial fertilizer. “If you are spreading urea fertilizer, you've got a homogeneous material and good control over the flow rate, and you've got a piece of history of the crop production for each grid point through the field. You can rely on automation to speed up and slow down the application rate of that single-component fertilizer.”
A three-component fertilizer makes it trickier to perform reliably accurate VRT, he adds. “The concentrations of each of those nutrients vary independently of each other.” Funk also says that even state-of-the-art application equipment lacks the technology to monitor nutrient levels on-the-go to ensure accuracy.
Know the value of what you apply.
To help producers recognize the financial contribution manure makes to a swine operation, Henze uses an algorithm program to create maps that assign dollar values for each nutrient applied. “For example, it tells how much nitrogen was put on a field in pounds (and dollars), just like if you had put on anhydrous ammonia or 28 percent N,” says Henze.
“In trying times, the producer can look at the banker and say, ‘yes, the hog enterprise has lost money, but if you put value on the manure, then the hogs broke even,'” Henze asserts. “Why not pay the hogs for the fertilizer?”
Livestock producers may be eligible for Environmental Quality Incentives Program (EQIP) contracts through the Natural Resources Conservation Service (NRCS) to help pay for more accurate manure application. EQIP offers contracts for payments (up to $300,000 per person or legal entity) to establish or implement conservation practices, including manure management systems, pest management, erosion control and other practices to improve and maintain the health of natural resources. Per-acre payment levels reflect technology costs such as GPS, application equipment, flow meters and rate controllers needed to make improvements. For more information, visit: http://www.nrcs.usda.gov/programs/eqip/.