Ag has role in nutrient management

Flaten made a presentation Oct. 24 to the Manitoba legislative committee reviewing Bill 24 to lift the hog barn moratorium in that province. This version has been edited for length.

My main purpose in participating in today’s session is to discuss some of the scientific principles for environmentally sound nutrient management practices, to help ensure that the policies developed by the province are developed accordingly.

In addition to my role as a professor who specializes in research, teaching and extension in nutrient management and crop nutrition, I have had opportunities to contribute to the science base for developing public policy on these issues while serving on various committees and task forces.

Basically, my comments can be summarized into two key messages: No. 1, our current scientific knowledge of nutrient management and water quality reinforces the importance of maintaining a strong regulatory focus on using the right rates, timings and placements for all forms of agricultural nutrients.

No. 2, that Manitoba should continue to invest in the science base that will guide us toward continuous refinement of those nutrient management practices.

As to item No. 1, water bodies such as Lake Winnipeg are challenged with nutrient loading from a wide range of sources, including municipal waste water, as well as agricultural and natural background sources. Within agriculture’s share of this loading, some of the nutrients come from commercial fertilizer and livestock manure, but the majority of nutrients come from vegetative residues and the soil itself.

Nevertheless, to minimize agriculture’s share of this nutrient loading, it’s important to continue along several paths:

  • Limit the accumulation of excess nitrogen and phosphorus in agricultural land to maximize the agronomic benefits and minimize the environmental risks. Manitoba has some of the most stringent nutrient management regulations in the world and we are the only province in Lake Winnipeg’s watershed that is regulating phosphorus applications. These regulations should continue to be in force and en-forced.
  • Restrict winter application of fertilizer and manure because snow melt runoff over frozen soil accounts for most runoff in our watersheds.
  • In Manitoba, we are fortunate; winter application of manure has been prohibited on Manitoba’s large livestock operations since 1999 and for all Manitoba’s livestock operations, regardless of size, since 2013.
  • Encourage manure injection or incorporation where runoff is likely to occur and especially when manure is applied in the fall. This has been in force in the Red River Valley for approximately 10 years. Fortunately, according to the 2006 census figures, at least 60 percent of solid manures and 83 percent of liquid manures were already being injected or incorporated in Manitoba.

On a side note, we will not make much progress toward reducing nutrient losses from agricultural land if we focus on only one of many sources, such as pig manure and, particularly, if we focus on anaerobic digestion as a manure treatment practice. Instead our policies should continue to encourage the universally sound principles of using the right rate, time and placement for all forms of nutrients.

As to item No. 2 , on the future development and maintenance of the science base that will guide us, for about 20 years, the Manitoba Livestock Manure Management Initiative (MLMMI), has provided outstanding leadership in supporting research, development and technology transfer for environmentally, economically and agronomically sound manure management practices.

I have been told that the MLMMI is being discontinued. However, I hope that the province will replace it with another broad-based group that will continue those constructive efforts.

In summary, sustainable nutrient management requires careful use of all forms of nutrients, whether they are in the form of municipal waste water, livestock manure or synthetic fertilizers.

A comprehensive suite of policies based on scientifically sound principles of sustainable nutrient stewardship should form the basis for public policies governing application of all forms of nutrients.

My impression is that Bill 24 will leave those policies intact, en-abling the province to focus on real solutions to the real challenges of improving agricultural and environmental sustainability.

Don Flaten is a professor in the University of Manitoba’s soil science department.

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Comments

  • John Fefchak

    Misleading the Public:
    Flaten tells us:
    Quote “Limit the accumulation of excess nitrogen and phosphorus in agricultural land to maximize the agronomic benefits and minimize the environmental risks. Manitoba has some of the most stringent nutrient management regulations in the world and we are the only province in Lake Winnipeg’s watershed that is regulating phosphorus applications. These regulations should continue to be in force and en-forced” unquote
    Seems to me, Flaten speaks with with different tongues sometimes; depending on the situation and where he is and who he is addressing; I suppose. He speaks about Manitoba having some of the most
    stringent nutrient management regulations in the world…read on.
    He knew full well that when the NDP government of Manitoba placed a top regulation
    limit of over 827 lbs. of available phosphorus per acre, he and they were helping the
    hog industry by compensating for the lack of manure spread acres with a ‘license to
    pollute’. Most crops use only 20 lbs. of phosphate a year.
    He was a main player in developing and recommending this regulation to the government. He knew then that industry was unwilling to incur the expense of transporting the manure from areas with too much to areas that could use it in a balanced way. They still don’t. To me, his involvement was an act of sabotage to Lake Winnipeg and Manitoba’s water sources.
    I can recall when the warning lights came on at 40-45 lbs. for phosphorus, during soil inspections. It was not regulated until January of 2006. That fact itself reveals the hog industry’s involvement in Manitoba.

    • old grouchy

      Sorry John – – – you may have been proud of 35 bu/acre crops of wheat (to only use 20# of phosphate per acre) but today I’m striving for double if not almost triple that so I get to use quite a bit more. Then when I have alfalfa fields – – – well I WANT to be using about 120# of phosphate – – – -I want those yields.
      Maybe you could update your facts to align with those from the 1990s – – – those from the 1950s are sort of out of date.

      • John Fefchak

        You cannot double or triple your bu/acre wheat crops by simply adding more phosphorus. Check it out!.. Prof. Don Flaten’s testimony to the Clean Environment Commission review of the hog industry where he wrote that the average crop removal rate in Manitoba was 20.47 lbs/acre. Of course there will be variations due to land type, heat units, rain, drought etc. Government develops policy to capture the greatest number of situations in a group. We aren’t talking about restricting what a crop will need and use in a year. We are talking about the residuals and the build up in soil to levels that far exceed agronomic need or value.
        The average is a general indication.

  • Denise

    Thank you to the University of British Columbia researchers for their work on the waters of Lake Winnipeg. We now know more about the neurotoxins found in the bluegreen algae linked to neurodegenerative diseases such as Alzheimer’s and ALS.
    news.ok.ubc.ca

  • Denise

    The University of British Columbia Okanagan researchers deserve recognition for the outstanding work they have done on the waters of Lake Winnipeg.
    They found a toxin (BMAA) which is linked to several neuro-degenerative diseases ,such as Alzheimer’s and ALS, in high concentrations during cyanobacteria (blue-green algae ) blooms.
    These toxic blue algae blooms can run for tens of miles in the lake. One photo from the air showed one bloom at least 60 kilometers long and several other blooms streaming across the lake beside it. The shore lines are often coated with the cyanobacteria which is dangerous for all wildlife, people, children and pets.
    news.ok.ubc.ca

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