Farmscape for September 19, 2008   (Episode 2964)

A University of Manitoba soil scientist suggests the key to successful management of nutrients, whether from manure or commercial fertilizer, is the correct timing, placement and rate of application.

Bill 17, which proposes a moratorium on swine barn development in most of eastern Manitoba, has been presented in the legislature for third reading.

Associate professor Dr. Don Flaten observes the key to sustainable nutrient management is applying the right source at the right rate with the right placement at the right time.

Clip-Dr. Don Flaten-University of Manitoba  
One of the tricks with livestock manure is that it doesn't come in a variety of different ratios of nitrogen to phosphorus.

You can't get it custom blended like a synthetic fertilizer and the way that the nitrogen and phosphorus balance is set up in most manures is that the N to P ratio in most manures is usually lower than what crops remove and so if you apply all the manure that's required to meet the crop's N requirements you usually end up over applying phosphorus.

One of the challenges for all livestock producers, not just pig producers, is to make sure that they don't over apply in terms of frequency.

If they apply manure to meet crops N requirements too frequently they'll end up with a build up of phosphorus on their land.

One of the great things about liquid pig manure is that it can be and often is injected underneath the soil surface.

That improves its agronomic efficiency and minimizes odour and also minimizes the risk of nutrient loss in surface water so placement under the soil surface is a good thing.

Then, in terms of timing, we certainly want to discourage the application of manure or fertilizer on frozen soils or snow.

Because, since 80 percent of our run-off occurs during snow melt in the prairies, we don't want that manure or fertilizer just sitting on top of the frozen ground or snow ready to go off with that snow melt.

Dr. Flaten says improved application technologies have made manure application more environmentally sustainable.

He notes the cost of most synthetic fertilizers have increased by 300 percent in the past couple of years which has improved the attractiveness of livestock manure.

For Farmscape.Ca, I'm Bruce Cochrane.

       *Farmscape is a presentation of Sask Pork and Manitoba Pork Council