Valuing Manure as a Seller or a Buyer
When talking about manure's value, one needs to think about a variety of factors. Most folks think of fertilizer nutrients as manure’s primary value or MVP, but it takes more than one or two star players to make a great team. As such, manure wouldn't be as great as it is without other characteristics like the added organic matter that you get when applying manure, or the microbial community that is added to your field with that application. The value of manure depends not only on the nutrient concentration in the manure, but also what the next crop requires, the condition of the soil, and whether or not commercial fertilizer will be used to supplement manure and make up for nutrient imbalances that often occur.
If you really don't need something, just how valuable is it? If you've got a really great team already, are you willing to pay a lot of money to transfer in a star player? To turn that around, if your soils are needing nutrients and could use some additional organic matter or microbial life, would you still sell the manure that could help you build that soil back up? It’s for this very reason that manure value changes for every field that it is applied to.
Nutrient value and the ability to offset commercial nutrient costs is relatively easy to put a dollar value on, but some of manure's valuable assets that aren't so easy to put a number on. Many people think of manure as a water quality problem, but because of its ability to improve water infiltration and holding capacity by increasing soil health, it can actually decrease risk of water quality impairment. Fields that have been receiving manure tend to have better infiltration rates and hold more water during a precipitation event, thereby decreasing runoff as compared to those fields that didn't receive manure. Additionally, fields that haven't received manure for several years - think 5-10 years - often notice a yield bump over fields that didn't receive manure. While the reason behind this effect is not well understood, many believe it is due to the microbial community that is introduced with the manure.
Another value that certainly can't be overlooked this year with fertilizer prices and availability so unfavorable is the fact that manure is most often a local nutrient that doesn't need to be hauled in on ships, trains and trucks over long distances from other locations. Over the years, local farmers probably applied nutrients to crops that were used to feed area livestock that then produce manure. The manure can and should be recycled back onto fields that will grow more feed for those animals creating a circular economy.
Of course, not all manure is created equal. Different animals eat different feeds in different proportions and therefore, they produce manures with different compositions of nutrients and consistencies. The only way to really know the nutrient content of the manure and whether the nutrients are balanced for what your crop needs, is to sample that manure and send to a lab for analysis. When talking about manure nutrients, we often focus mainly on nitrogen (N), phosphorus (P), and potassium (K), but other nutrients that plants need are also found in manures. Secondary nutrients like sulfur (S) and micronutrients like zinc (Zn) are good examples. When these nutrients are needed, they boost manure value because they help offset additional commercial fertilizer costs.
Nebraska Extension offers a Manure Value Calculator that is available to calculate the dollar value of manure nutrients. It’s currently available at go.unl.edu/manurevalue. The calculator is an Excel tool that helps determine the value of the manure nutrients and a potential yield increase. To use the calculator for your manure, you need to gather the following information:
- soil and manure information including an analysis for each,
- next year’s cropping plan including nutrient recommendations and how you plan on applying the manure, and
- current fertilizer prices for N, P, K, S and Zn.
The tool can be used to determine a hypothetical value for manure you plan to sell by using estimated soil values, or it can be used to compare manure from different sources to determine which is the most economical for your field. For the latter situation where you are purchasing manure or paying someone for the application, you will also need this cost to input into the spreadsheet. Remember though, when determining a value for selling manure, buyers will need to factor in transport and application costs, so don’t set your price too high!
There are other manure value calculators out there. University of Minnesota has an online one and I’m sure there are others. There might even be an app for that. No matter what tool you use, whether you’re buying or selling manure, remember that there’s more benefit to using manure than just the nutrient value. It’s just harder to put a real dollar value on some of those things.