Discovering root cause important in wet area management in fields
As planting season approaches after a wet spring for some areas of the state, as well as for producers who utilize irrigation, effectively managing wet areas of fields is important for optimizing crop production.
University of Wyoming Assistant Professor of Agronomy and Cropping Systems Carrie Eberle gives producers helpful tips for identifying potential problem areas, as well as important considerations when deciding how to manage wet areas.
Impacts
While having water is generally good, particularly in the West, wet areas in a field can result in problems for growers.
“When we see producers who are chomping at the bit to get out into their fields, get their ground worked and get the crop in, if the soils are wet, we see a lot of issues with compaction, both from our tillage and from our equipment,” says Eberle.
Soil compaction can be extremely detrimental to crop production, as it affects root development.
If possible, Eberle explains that the best option for wet soils in the spring is to wait until fields dry out.
“The potential for long-term compaction damage is so high, and we’re going to take a lot of time to recover from that,” she comments.
Eberle also explains that wet soils warm up more slowly than dry soils, so it is important for growers to pay attention to soil temperature.
“If we’re dealing with a wet soil, we want to delay planting to make sure that the soil is an appropriate temperature for the seed,” she notes. “We don’t want the seed sitting in a cold, wet soil. That can cause a lot of disease and other issues.”
Strategy
According to Eberle, different strategies should be used for managing wet spots in a field, depending on the water source.
“There’s rain-fed and natural water that can cause excess wetness, and then there are irrigation issues where we have runoff and ponding,” she says.
In areas where natural water causes the problem, strategies such as drain tiles can be used. However, Eberle does not recommend those for irrigated fields.
“They’re a pretty big undertaking to put into a field, and if we’re talking about irrigated fields, we’re better off managing our field to where we’re not dealing with excess water,” continues Eberle.
“In irrigation situations, the ways to offset excess water are going to be very different because that has to do more with their management and getting the best use out of their irrigation,” she comments.
Managing
“When we have irrigation fields that we’re seeing a lot of ponding and pooling of water in, the problem can be caused by a number of different things,” comments Eberle.
One possible cause is a hardpan layer that prevents water from infiltrating deeply, which needs to be managed with tillage.
Oftentimes, in heavy tillage soils, Eberle notes that loss of soil structure can be a problem, which she uses an analogy of a sponge to explain.
“Imagine we have a sponge and all of the holes in the sponge are an avenue for that water to soak in and have a place to go,” she says. “If we take that sponge and compact it into a little ball, it’s not going to hold as much water, and it’s going to take longer to infiltrate.”
To offset the loss of soil structure, producers can use strategies such as cover crops, reducing tillage and slower irrigation rates.
“If we usually put on an inch of water, we can transition to putting on 0.5 inches of water twice in the same period,” comments Eberle.
Variability
Managing fields that have both wet and dry areas becomes a much more complex issue, says Eberle.
“It gets to the ‘why’ of what’s going on, so one thing I would suggest for a grower to do that’s having issues is try and get their local Extension agent or crop consultant to try and help them,” she continues.
Once wet problem areas have been identified, the next goal is to identify why producers are seeing the problem.
“It could be a matter of heavy compaction in one area or different soil organic matter in that area,” comments Eberle. “Then, they can start to come up with a plan to balance that back out and fix the issue.”
She explains that the goal is to treat the problem, rather than the symptom that producers are seeing and then use management strategies to mitigate the root problem.
She concludes, “If our field has issues, how can we use our crop rotation, our cover crops and tillage management to bring everything back up to the highest quality we can get it?”
Emilee Gibb is editor of Wyoming Livestock Roundup and can be reached at emilee@wylr.net.
