Winter manure management considerations

“Extreme weather events, full manure storages, delayed harvest or contractor availability may be some of the most common reasons a farm operator may need to spread manure on frozen and/or snow-covered ground,” says Trevor Wallace, provincial nutrient management specialist with the Alberta government. “However, when the ground is frozen or snow-covered, the risk of losing applied manure and nutrients in runoff is much greater due to limited soil infiltration, reduced vegetative filtering and increased runoff potential. It is important to be aware of the increased risks and to know your options to manage them.”

Adopt strategies to avoid emergency situations and the need to spread manure on frozen or snow-covered ground. Strategies could include regular maintenance and inspection of the equipment and facilities. Consider increasing the frequency of inspections with aging infrastructure. Well-planned inspections identify wear, damage and maintenance issues before there is a problem. Create a checklist and a schedule to find weak points in the system so that they are not overlooked, and keep those records should a Natural Resources Conservation Board (NRCB) inspector ask to see them.

“If your storage facilities cannot hold the manure produced through the winter, perhaps it is time to increase your storage capacity,” points out Wallace.

This can be done by constructing additional storage facility capacity to provide a total 12 to 18 months manure production, which will:

• allow spreading manure at a better time for crops to uptake those nutrients
• reduce spreading frequency thereby reducing time to deal with logistics
• avoid emergencies and thus reduce stress and improve your mental health, and
• improve neighbour and community relationships

Another way to increase capacity for solid manure is to use short-term or temporary manure storage. Under the Agricultural Operation Practices Act (AOPA), manure can be stored in a short-term manure storage for an accumulated total of 7 months over a 3-year period.

“This limitation reduces the risks from storing manure such as nutrient accumulation, runoff and leaching. Site selection can further reduce these impacts and minimize concerns from neighbours and the community.”

If spreading is the only option, the first step to managing risks related to spreading manure on frozen or snow-covered land is to contact the nearest NRCB inspector to discuss the situation. The NRCB may or may not grant permission depending on the reasons for spreading, type of manure and the site-specific circumstances. The NRCB will:

• meet and work with you to assess the situation
• confirm if the field is frozen or snow-covered, if needed
• help you to decide what steps can be taken to reduce risk, if any, and
• tell you what specific requirements must be met to ensure spreading will not cause a risk to the environment or inappropriate nuisance as per the regulations under the AOPA

How can you tell if the ground is frozen or snow-covered? Alberta developed a Frozen and Snow-Covered Land Technical Guideline that provides the following tests:

Frozen – the soil is impenetrable as a result of freezing temperatures, or more than one third of the top 15 cm (6 in) contains frozen soil water
Snow-covered – more than 50% of the field is covered by an average snow depth of more than 5 cm (2 in) from the ground surface