As fertilizer prices rise, manure values are going along for the ride, says Paul T. Kivlin, University of Wisconsin (UW) Extension nutrient management specialist, UW River Falls. Perceptions of manure are also continuing to evolve as values increase. “Once valued as a fertilizer, manure may be viewed more as a byproduct of livestock production. In truth, manure is not a liability, it is an asset,” Kivlin says. “Just in the last two years, we have seen a 150% increase in nitrogen prices, a 170% increase in phosphorus prices, and a 240% increase in potassium prices,” he continues. “At the same time, it has become very important for us to value manure appropriately and not just view it from a regulatory standpoint.”
Kivlin reminds producers that manure nutrients offer important benefits. Phosphorus, for example is needed for good plant growth. “Some folks are so afraid of phosphorus because of the regulatory issues that come with it,” he states. “We have to handle phosphorus correctly, but we need it for good crop production. Manure is a fantastic product when we look at providing nitrogen, phosphorus and potassium to our plants and it also offers sulfur and boron, for example, and is an abundant source of organic matter.”
Producers need to take a similar approach to utilizing manure nutrients as they would if they were buying commercial fertilizer, according to Kivlin. “Nutrient management planning consists of taking a look at four key management numbers,” he explains. “(Those numbers include) what your crops need, what your manure supply is, what your legume crop supply is and what, if any, additional fertilizer is needed.”
Producers should ask how much nitrogen, phosphorus and potassium can be obtained from the manure they have. There are two ways of obtaining that information. Book values are available for a number of animal species. The values are averages that have been compiled based on research and laboratory analyses. Laboratory analysis of the specific manure sample is the other method of determining value, according to Kivlin.
Whether book value of manure or actual laboratory analysis is used depends on the type of operation, manure storage method and animal species. When dairy barns are being cleaned and manure is being hauled every day for example, Kivlin advises producers to use book values. “About 50% of the nitrogen is in feces, and the other 50% of the nitrogen is in the urine, while most of the phosphorus is in the feces, and most of the potassium is in the urine. This can make it hard to get a representative sample,” he explains.
He tells most producers who have liquid manure handling systems or stacked manure systems to have samples analyzed in a laboratory. “With liquid systems, you can have a lot of variation in terms of agitation,” he explains. “It is often recommended that you take three samples, one at the beginning third, middle and end when emptying the pit.”
Kivlin offers these four manure marketing considerations:
- Agitate aggressively – good agitation helps produce a consistent product.
- Analyze the product – provide a laboratory analysis for your customer so he knows the nutrient value of that product.
- Apply accurately – this is especially true for dairies or other livestock producers who may be moving manure to a cash grain operation that might not have a manure spreader and may be using the livestock producer’s spreader. “It is important to calibrate the manure spreader,” Kivlin says. “A 20-ton/acre application rate may be equivalent to applying $222/acre in nitrogen, phosphorus and potassium values, whereas, a 60-ton/acre application rate may be equivalent to $666/acre. The application rate is really key when you are figuring out what you can get out of this valuable resource.”
- Practice environmental awareness - know the setbacks and phosphorus restrictions.
“Remember, the value of manure to folks who aren’t used to manure usually shows up in how the crops do the following growing season after application,” Kivlin concludes.