Take Advantage of Manure Resources for Your Operation

Take Advantage of Manure Resources for Your Operation

January 9, 2009

Charles Wortmann, Extension Soils Specialist

Added profit over three-year life of application:
$23.81 to $424.18
Based on $0.67/pound nitrogen and $0.98/pound phosphate

The value of feedlot manure to crop producers can range from $0 to more than $25 per ton, depending on the quality of the manure and its water content, the soil to which it is applied, and the crops grown. Depending on the nutrient needs of a particular field, a manure application can add profit of $23.81 to $424.18 per acre over a three-year period.

Manure can provide the nutrients or soil amendment needed for optimum crop yields. Manure nutrient content and value varies widely due to weather conditions, the livestock facility and manure storage systems, the age of the manure, and feed composition. Increased moisture content of manure reduces its value as it dilutes its benefits on a weight or volume basis and results in increased transport costs. A crop producer needs to consider several factors when determining the value of manure.

Table 1. Nutrient content of beef feedlot manure on an "as is" basis.

 Nutrient
Lbs per ton
 Ammonium N
2
 Organic N
16
 Phosphate (P2O5)
18
 Potassium (K20)
14
 Sulfur
5
 Zinc
0.03
  • What is the nutrient content of the manure and how much will be available to the crop?
  • What are the nutrient needs of current and future crops? (This might be estimated for a four-year period.)
  • Should value be given for building soil nutrient levels?
  • In addition to adding nutrients, will the manure improve crop yields due to other soil improvements?
  • How much will the crop producer need to pay for manure transport and application?
  • Will manure odors be a problem or are there any other problems with manure use?
  • Will the manure be evenly spread and will the sample results be truly representative for the manure applied?

Consider: Manure generally contains nutrients that do not need to be applied for optimal crop performance and which may be of no value to the crop producer (Table 1). Not all of the nitrogen applied will be available to the crop since ammonium N can be lost to the air and much of the organic N doesn't become available for one or more years.

Table 2. Yield summary of 20 sites comparing manure and fertilizer use in Nebraska.

 Crop
Number of sites
Fertilizer only
Manure plus fertilizer
Field difference
 
----- bu/ac -----
 Corn
14
164
171
7
 Soybean
6
49
51
2
 Summarized by Richard Deloughery, 2003.

Valuing Manure for Your Operation

Value can be given for building soil nutrient levels in cases of very low to medium nutrient availability. These nutrients will not result in increased yield in the short-term and the producer may use lower prices when determining the dollar value of each nutrient.

The organic material in manure can improve yields by increasing the water infiltration rate and water-holding capacity (Table 2) of the soil. On some soils, the organic matter in manure may be worth two or three times its nitrogen and phosphorus value, but it may have no value on other soils. This value typically is between $0 and $30 per acre.

A NebGuide (Calculating the Value of Manure for Crop Production, G1519) and a computer program (Nebraska Manure Value Calculator) are available for calculating the value of manure. See the Web site http://water.unl.edu/mmresources/software for free access to these tools.

How Application Site Affects Value

The value of manure varies, depending on where it is applied. To illustrate this, let's consider beef feedlot manure applied to two different fields.

Both fields are in corn-soybean rotation with manure applied before corn. The expected yield of corn is 130 bu/ac. The soils are medium texture and crops do not respond to applied sulfur. The corn crop on both fields needs 90 lb/ac nitrogen which can be supplied in the year of manure application by applying 18 tons/ac.

The soil of Field 1 has 12 ppm Bray-1 P, 205 ppm K and 0.7 ppm Zn. The farmer decides to give credit to some of the manure P for increasing soil P availability. This field has no history of manure application and the farmer expects yield increases due to manure use during the next three years to be worth $41.50. The net value of the 18 tons of manure, with $0.67 lb of N, is $424.18 per acre, or $24.36 per ton before application costs (Example 1).

The soil of Field 2 has 40 ppm Bray-1 P, 300 ppm K and 1.8 ppm Zn. The farmer does not give credit to manure nutrients for increasing soil nutrient availability. This field has regularly received manure in the past and the farmer does not expect yield increases due to manure application as compared to using only fertilizer. Therefore, the farmer only gives value to the manure N that will be available over the next four years. The value of 18 tons of manure for this field, with $0.67 lb of N, is only $73.81 per acre, or $4.10 per ton before application costs (Example 2).

The two fields are quite similar but the value of manure use on Field 1 is nearly six times greater than the value of using the same manure on Field 2. Feed operations charge differently for manure delivery and application. Assuming the cost of delivery, application and incorporation of the 18 tons of manure is $50 per acre, the first scenario gives a net gain of $374.18 per acre while the second scenario results in a gain of only $23.81 per acre.