Author: Max Runge

Baling wheat straw following harvest is seen as a way of utilizing a bi-product, with the only cost being baling and removal from the field. The straw could then be sold as bedding for livestock, mulch, or other uses that provide value. However, the cost may be larger than you think.

The cost of fertilizer and increased focus on soil health makes it essential that we know what nutrients we are removing from the field when we take away the wheat straw. Research has shown that removing 6,000 pounds of wheat straw per acre removes valuable nutrients (6,000 pounds is the approximate amount of straw associated with an 80 bushel per acre wheat yield.) Removing this quantity of wheat straw removes 60 pounds of Nitrogen (N), 10 pounds of phosphorus (P2O5), and 135 pounds of Potash (K2O), per acre¹. This is in addition to the nutrients removed when the wheat grain is harvested.  Putting a monetary value to the pounds of N, P, and K taken away by baling the straw shows that the straw does have significant value. A price of $.86 per pound of nitrogen, $0.70 per pound of phosphorus, and $0.61 per pound of potash² were used to reflect the approximate cost of the nutrients. The table below shows the value of the N, P, and K removed on a per acre basis when the wheat straw is removed. The value of the wheat straw needs to be greater than $125.47 per acre or $25.09 per 1200-pound round bale. Adding the cost of baling (1200 lbs. round bale) of $14.50³ per bale and moving³ the bales out of the field at $4.35 per bale. The total of these costs is $43.94 per bale or $219.72 per acre. It should be noted that this is just the value of N, P, and K. There are some micronutrients as well as the organic matter that wasn’t considered in this analysis that have value if left in the field.

There are caveats. The amount of straw could be different depending on numerous factors, including limited yield, variety of wheat, the efficiency of the baler, and soil type. The value of N, P, and K will vary depending on your location as well. Check local resources in your area to estimate the value/cost of the removal of wheat straw. 

Information for the values included in this article can be found in the following resources.

1. https://www.aces.edu/wp-content/uploads/2019/01/ANR-0449.REV_.3.pdf
2. https://www.ams.usda.gov/market-news/production-cost
3. http://agecon.ca.uky.edu/files/custom_machinery_rates_applicable_to_kentucky_2022.pdf

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Runge, Max. “Wheat Straw Nutrient Removal.” Southern Ag Today 3(13.3). March 28, 2023. Permalink

The increased cost of fertilizers has many users asking where fertility costs can be reduced.  Soil testing has long been recommended for farmers, ranchers, and homeowners to identify fertility levels and enable them to only purchase/apply that which is needed.  In addition to replacing the right amount of nutrients, it’s important to consider the conditions which make the most efficient use of existing and applied nutrients.  One component of a fertility program (and soil testing) that should not be overlooked is identifying and correcting low pH through the application of agricultural lime.  Agricultural lime is an investment that will leverage  high-cost fertilization by providing improved nutrient utilization in row crops, forages, and most other agricultural crops we grow in the S.E. United States. . 

Figure 1. How Soil pH Affects Availability of Plant Nutrients

Figure 1 shows the range of soil pH that provides that greatest plant utilization of the listed nutrients in the soil. If the soil pH is out of the target range, the nutrients aren’t utilized as efficiently. It should be noted that higher pH range may result in less utilization of some micronutrients.  It is important to know the major nutrient and micronutrient requirements of the selected crop or forage.

There are various materials that are used for liming, and they have different attributes. Check with your supplier about what liming materials are available. Many states have regulations or laws associated with the characteristics and efficiency of materials that can be marketed as agricultural lime. 

It typically takes one to two months after an application of a liming material before it becomes effective, so plan accordingly. 

Producers should check with their land grant university for soil testing related information.  

Runge, Max. “The Value of Proper Soil pH“. Southern Ag Today 2(19.3). Permalink