Friday, September 07, 2007

NPS Nutrient Management

We hope you can provide us with insight—your experience is invaluable to us. We need your input on the role you think that our sciences can play in achieving both yield and national NPS pollution abatement needs.

Some Food for Thought:
  1. Are there programs, specific areas of research, methods of working with producers, or tranportation and other incentives that can be used to effectively reduce NPS pollution?
  2. Who are the stakeholders involed in NPS pollution mitigation?
  3. Are there success stories we can learn from?
Please comment or send information to
We will post a more indepth analysis of NPS pollution abatement options in the coming weeks as we gather information and develop a better understanding of the topic.


Anonymous said...

Hi Caron. Good try to get some discussion and gather some input. We ARE the organization that should be providing input about what can be done on the ground about NPS nutrient pollution. Obviously not easy to get going since I'm the first one to comment 2+ months after you set up the framework.

Keeping nitrogen out of water without sacrificing yield has been the main thing I've worked on over the past ten years. My observations are:
1) Unused soil nitrate after harvest is much higher when nitrogen fertilizer is over-applied than when applied at the rate actually needed by the crop (JEQ 36:354-362).
2) It's difficult not to over-apply, because of the high variability in how much nitrogen is needed both among fields (Agron J 95:994-999) and within fields (Agron J 97:452-461).
3) Accurate diagnosis of the right N rate is a huge need to avoid NPS pollution from nitrogen fertilizer. This has been difficult to provide to producers.
4) Applying nitrogen too early also contributes greatly to NPS pollution. 'Too early' depends a lot on the N source and the weather.
5) Plant color can give considerably more accurate diagnosis of nitrogen need than soil tests (Agron J 98:655-665).
6) We've done 26 on-farm demos over the past three years using color (reflectance) sensors to control nitrogen rate. We've reduced fertilizer rates by 28 lb N/acre while losing 1 bushel/acre of yield. We have taken as much nitrogen off (in the grain) from those fields as we applied.
7) NRCS has approved sensor-guided fertilization of corn as an EQIP practice in Missouri, helping producers to overcome the capital investment and learning-curve barriers to adopting this technology.
8) I think there is good potential to reduce NPS pollution while maintaining high yields using the sensor approach.

Thanks for the opportunity to comment.

Peter Scharf

Anonymous said...

I believe that the Tri-Societies and our members have several roles in NPS Nutrient Management:
1. Continue to support funding for and carry out research on nutrient management practices, including not only the crop response, but also the environmental response.
2. Provide essential research-based information for and participate in the development of nutrient management practice recommendations and standards.
3. Set a clear expectation that our certified advisors will follow these recommendations and standards in their professional activities just as any other professional is expected to follow best practices of the profession to maintain certification.

We have a good example from industry itself. In the article titled "Anhydrous held until soil temps drop", Iowa Farmer Today (Vol 24, No. 10, Nov. 10, 2007) by Tim Hoskins, he describes how some of the retailers in Iowa use a fall nitrogen code of practice. "Members of the Agriculture's Clean Water Alliance, a group of retailers in the Raccoon River Watershed, have agreed not to distribute anhydrous ammonia for fall application until soil temperatures drop to 50 degrees and are cooling or sell anhydrous ammonia with a nitrogen stabilizer until soil temperatures are 60 degrees and cooling. 'We are bound by that code,' says Harry Ahrenholtz with West Central Co-op. It seems like it one thing the retailers can agree on, even though they compete against each other. 'We monitor each other,' says Dave Coppess with Heartland Co-op and president of Agriculture's Clean Water Alliance. He says if one of their employees sees someone applying ammonia when soil temperatures have not dropped, they call other retailers to see if it is their customer.
The retailers represent more than 90 percent of the amount of nitrogen sold in the watershed. "

Thanks for the opportunity to comment,

Leslie (Les) Everett
Water Resources Center
University of Minnesota
173 McNeal Hall
1985 Buford Ave
St. Paul, MN 55108
tel 612-625-6751
fax 612-625-1263

Anonymous said...

Below is a link to an article published in the Ethanol Producers magazine regarding research on energy production from soybean straw that maybe of interest to you.

While much attention has been given to the use of corn stover as a biofuel, very little attention has been given to the potential for Bioenergy from soybean straw despite the fact that soybean is grown on 60 to 80 million acres in the US. Much of this acreage is in rotation with corn and the feasibility of harvesting stover or straw needs to be evaluated as part of the total rotation system. The capacity of soybean to produce carbon without requiring nitrogen fertilization should be considered as an option in projecting biofuel production by US agriculture.