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Managing irrigated manure – Audio

Manure irrigation management

Rebecca Larson, Assistant Professor
Department of Biological Systems Engineering
UW-Madison College of Agricultural and Life Sciences
(608) 890-3171

2:58 – Total Time

0:22 – How irrigation is used to spread manure
0:39 – Benefits of irrigating manure
1:08 – Challenges to use of irrigation for manure
1:30 – Research into the practice
1:54 – Research findings
2:15 – Best management practices
2:48 – Lead out

Sevie Kenyon: Pros and cons of using irrigation equipment to spread manure. We’re visiting today with Becky Larson, Department of Biological Systems Engineering, University of Wisconsin-Madison Extension and the College of Agricultural and Life Sciences now celebrating 125 years and I’m Sevie Kenyon. Becky, first of all tell us how people use irrigation equipment to spread manure?

Becky Larson: So around the state people use irrigation equipment to spray manure from center pivot systems and traveling gun systems, particularly at times when conventional equipment like tankers can’t go out into the field.

Sevie Kenyon: And what are some of the benefits of such a system?

Becky Larson: Well one of those benefits are that you can use the equipment when the field is wet, you can apply manure at a little bit lower cost than other systems, you reduce road traffic from conventional spreading equipment where you have to haul the manure on the road and we also see that you can get some water quality benefits by applying manure throughout the growing season.

Sevie Kenyon: What are some of the challenges to using irrigation equipment for manure?

Becky Larson: Well we have some difficulties to weigh. We have a lot of pathogen transport, we’re concerned with how far those pathogens move in the air. We’re also concerned with odors and we’re also concerned with there may be some potential negative water quality issues and air quality issues that we’re still trying to evaluate.

Sevie Kenyon: Perhaps you could tell us a little bit about some of the work you’re doing with this issue?
Becky Larson: Particularly with the research, we are measuring how far pathogens are traveling when we’re spraying with center pivot systems and traveling gun systems. And then we also have a work group that’s trying to evaluate in terms of a variety of different impact factors, how manure irrigation might affect benefits and the drawbacks.

Sevie Kenyon: What are you finding so far with this research?

Becky Larson: So far we have seen that as distance increases, pathogens don’t travel as far. So we see a reduction in the concentration as distance increases indicating that there will probably be a safe distance at some point where you wouldn’t be at as much risk.

Sevie Kenyon: And Becky perhaps you can describe some best management practices that we should see being used?

Becky Larson: Very simple ones are: try to use wind speeds under 10 mph when you’re using these practices. Try too, when the wind is blowing in direction of where people may reside or be outside, that’s probably not the technology you want to use and probably not that day. So there are some pretty simple management things we can do to limit some of the drawbacks of the practice. You can also spray during sunny days when the UV intensity may be high and will actually inactivate some of the pathogens.

Sevie Kenyon: We’ve been visiting with Becky Larson, Department of Biological Systems Engineering, University of Wisconsin-Madison Extension and the College of Agricultural and Life Sciences and I’m Sevie Kenyon