Matt Steinert, Enid, Oklahoma, says their dryland corn is “a train wreck. We will have an above-average irrigated corn crop, but we had to pump a lot of water.” 

Steinert says managing irrigation in a region that averages 30 to 32 inches of rainfall a year can be challenging. 

“Some years we pump only 8 to10 inches; others, like this year, we had to pump every inch to make a crop.  

“Irrigation is a big deal for us,” Steinert says. “Most years we get 60% of the rainfall we need to raise a crop. But we are prone to “flash droughts” that might last two weeks, so we have to bridge the gap with irrigation. We can be extremely efficient with irrigation water in terms of bushels per inch of water applied.” 

His family raises corn, wheat, and soybeans and irrigates about one-third of their acreage, mostly with Valley pivots, plus 150 acres of row flood. 

“We’ve tried several systems to improve water efficiency,” he says. “We have installed moisture probes and utilize satellite imagery, but we have gone back to managing by evapotranspiration models.  

“The logistic of installing and removing probes is an issue.  “We have a mix of slow-infiltrating soils and soils with low water holding capacity. When you combine that with ET rates approaching 3/4 of an inch per day there isn’t a lot of margin for error.   

Catch 22 

“The moisture probes have shown us that we are depleting soil moisture at depth throughout the season and only moving irrigation water into the top 8 to 10 inches of the profile. We are in a catch-22, we need to apply water more slowly and increase application depth to move water deeper in the profile, but if we reduce pumping rates we can’t keep up with peak ET. The compromise is we end up running a lot of half-inch passes.  

 “The moisture probes on flood-irrigated ground we developed last year were fascinating to watch. We could let the profile dry out much more compared to the pivot-irrigated field down the road, then run a 2-inch set and move water to 30-inch depth.” 

Rotation 

Crop rotation helps, he says. “For one thing, it helps spread out our workload by spreading out peak water use. Most years, we will be nearly finished watering corn before we need to start watering double-crop soybeans hard.”  

Rotation includes corn, wheat, and double-crop soybeans.  

“Occasionally, we might shift things a bit and run corn on corn. We also plant rye as a winter cover to graze. We also plant some single-crop beans.” 

Reduced tillage, Steinert says, has been a crucial piece of moisture management. “We utilize strip-tillage and vertical tillage. We will make a pass with a high-speed disk in front of irrigated wheat. If we plant wheat into irrigated corn stalks without some kind of tillage, there is just too much residue on the surface.  That residue  will insulate the ground, preventing heat from radiating up into the crop canopy, and we will see more freeze injury.”   

He says the residue is critical. “No question, we have to have residue because we have soil with slow infiltration rates and sandy soils vulnerable to wind erosion.” 

He says an unusual situation this year shows the advantage of residue. “We moved a lot of dirt in one field, leveling to fix drainage. That created a clean-till situation where we could not drive water into the profile.”  

New ground issues 

Taking on new ground also offers challenges, he says. 

“Often, new ground is a recipe for failure; soils are simply not in condition to make a summer crop. In many cases, there is a reason someone gave it up.” 

Steinert says residue make a big difference in dryland, summer crop acreage, particularly soybeans. “We have added more acres of soybeans with no-till. Several counties in this area account for some of the largest concentrations of double-crop soybeans in the nation.” 

Steinert says his dad adopted reduced-till more than 30 years ago. “He started in 1995 and by 1998 he was 100% no-till or minimum-till.” 

He’s “pretty well committed to more strip till next year. We can target nutrient placement, and in a lot of cases we need to break surface compaction, especially when we’re raising three crops in two years, which puts a lot of traffic on the field and a lot of compaction in wheel tracks.” 

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