Applying manure: How much is too much?

With harvest wrapping up in many parts of the country, the race is now on to get all the things you need to get down before the ground is frozen and covered in snow. One of those tasks may be taking manure from the corrals or barns and spreading it in the field. But how much is too much?

Conduct tests

Agrium senior agronomist Ray Dowbenko says it is important to carry out tests of your soil and manure.

“If producers are soil testing, which they should be, they will recognize what kind of nutrients they need to apply or the amount they need to apply and then they can look at the manure analysis and that would be the nitrogen, phosphate, potash and sulphur,” says Dowbenko.

“They can then apply based on the phosphate from the environmental perspective and then look at the nitrogen value,” he adds. “Really, they should be looking at applying for the phosphate value and that will reduce the pressure on the environment.”

In action

This is something they do routinely at South Slope Feeders in Rainier, Alberta, according to general manager Mike Graham.

“Everything we do is soil tested and the manure is applied accordingly; typically in the fall we do our soil analysis and our plan for the upcoming year and do what the requirements are,” says Graham.

This has allowed them to improve on what they are doing.

“We found over time the concentration is building and so we’ve put less tonnage on than we have in previous years and match it up a little closer to the uptake.”

Some specifics

Dowbenko says soils that are sandier in texture and low on organic matter are the best suited for manure.

“Those are good candidates for manure application,” he says. “They will have the most benefit.”

On that note, Dowbenko says hilltops that face wind and water erosion are often low on both phosphate and organic matter, which is why they are great for application if producers can manage it. As well, fields that are going to grow cereals and oilseed crops next year are the ones in need of manure.

Bottom line

Soil testing to analyze nutrients will determine what and where manure could be applied. For more information on manure application, Dowbenko says provincial government websites should have rates and regulations.

Article by: Craig Lester