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August 13, 2020

How To Make The Most Out Of Fall Manure Application

Manure can benefit an operation’s soil nutrient system and overall crop production. By incorporating manure into the field, crop yields increase, soil nutrient levels improve, and micronutrients are boosted. Manure also provides valuable organic matter to soil that fosters soil tilth, aids in the restoration of water and nutrients, and promotes the growth of beneficial micro-organisms. We have assembled some tips that’ll help you get the most out of your fall manure application. 

Soil Temperatures

Fall manure application allows for more time for organic portions of the manure to break down before the crops need the nutrients, compared to spring application. Harvest season application can also increase the likelihood of potential nitrogen loss. During fall application, one should avoid coarser-textured soils where leaching can be a threat to water quality in surrounding waterways. We recommend that fall application should start when the soil temperatures at six-inches deep are below 50 degrees Fahrenheit (10 degrees Celsius). Ideally, the best soil temperature for fall application hovers around a window between 50 degrees Fahrenheit and 35 degrees Fahrenheit. 

Waiting until the soil cools ensures that crop nutrient uptake increases and nutrient loss due to runoff and leaching are reduced. If manure is applied when the soil’s temperature is above 50 degrees Fahrenheit, then the inorganic nitrogen coverts rapidly to nitrate-nitrogen. Nitrate-nitrogen is a very mobile form of nitrogen that increases the risk of nitrogen, leaving the groundwaters. 

Timing for Manure Application

Research done by the University of Minnesota Southern Research and Outreach Center shows that in on-farm strip trials over two years, the overall yield between early fall application and late fall application differs. The yields from the September (early) manure application were lower than that of the October-November average (late) application. Early slurry treatment in September resulted in a yield of 190 bushels per acre. Late manure treatment in October-November resulted in a yield of 200 bushels per acre. 

All of the nitrogen processes are controlled by soil type and rainfall patterns. Generally, early fall manure application increases the risk for leaching and denitrification losses since there is no crop present for nitrogen uptake. Liquid swine slurry with a high inorganic nitrogen content should be managed much like inorganic fertilizer nitrogen sources, with either late fall or spring application to delay the conversion of ammonium to nitrate and subsequent loss by leaching and denitrification.

Incorporate Manure and Record Application

Injecting manure directly under the soil surface is the preferred method to maximize nutrient benefit, maximize odor control, and minimize runoff. This reduces nitrogen loss to the air and/or runoff and allows the soil micro-organism to decompose the organic matter in manure, making nutrients available to the crops faster.

After application, take a minute to record your actions for future reference. Application records should include soil fertility test reports, manure analysis reports, date(s) of application(s), rate of slurry applied (gallons or wet tons per acre), previous crops are grown on the field, and yield of past harvested crops. Each field and operation is different. By keeping records of your application, you will be able to apply manure more effectively and maximize yield for each field the next time application is needed. 

Applicators that utilize Puck Enterprises’ LightSpeedTM and LightSpeed Pro, an industry-leading pump control system, have access to premier performance recording, operations mapping, and reporting tools. LightSpeed is accessible through devices with access to the internet or cellular network, giving users instant access to their application data while on the go. 

To learn more about manure application and Puck Enterprises’ application equipment, register for upcoming Pump School events. The dates of future Pump Schools will be posted on our events page and social media channels.