Stretching the H20
Sunday, January 15, 2006
filed under: Irrigation/Water Use
As with many producers around northeastern Colorado, a half dozen years of drought have forced Gene Bauerle and Josh Leahman to stretch their water - be it in the form of irrigation or natural precipitation - more efficiently than ever. For these father-in-law/son-in-law farming partners, that conservation program stands on three legs: (1) ample residue cover, (2) limited irrigation and (3) reduced plant populations.
Bauerle and Lechman, who farm midway between Julesburg and Holyoke in Sedgwick County, are basically dryland producers. Adding a second center pivot to their irrigated acreage in 1996 did not mean access to more water.
They still had just a single well permit ‹ meaning they could draw upon only their historical 172-acre-feet of water for both circles. "that's the reason we're limited irrigation," acknowledges Bauerle, who has served 12 years on the Colorado Groundwater Commission.
With sunflower, wheat and corn in the rotation, one of these three crops' acreage will be totally dryland in a given year, with 120 acres of the other two under adjacent circles. While their well pumps at about 750 gallons per minute, Bauerle and Lechman rely on reduced populations, prior crop residue and offset timing to keep yields and quality up on their irrigated acreage.
In 2005, for example, their seed drop on irrigated corn was 18,000 - compared to 30,-32,000 under "normal" moisture conditions. For confection sunflower under irrigation in 2004, they dropped about 16,500 seeds per acre that spring. They like to go into the season with a full moisture profile so they don't have to water up the crop - and were able to do so as recently as '04.
While one would presume corn to be the biggest water consumer of the triad, Bauerle and Lechman say for them it's actually wheat. "We've put 10 inches of water on wheat [each of] the last two years," Bauerle relates. By comparison, they applied just seven inches on their 2005 corn circle; and, in 2004, only about 4.5 inches on their confection 'flowers. (Sunflower was the 'odd crop out' in 2005, so all their 'flower acreage was dryland.) They attribute wheat's irrigation needs to the preceding sunflower crop¹s ability to draw deep-profile moisture.
"We feel the wheat 'makes' the corn and sunflower," Bauerle says, referring to the ample wheat residue that carries over into the corn and then sunflower crops that follow. Along with helping retain soil moisture, the wheat residue reduces field runoff during irrigation and natural rainfall events, Lechman adds.
On sunflower ground going into wheat, Bauerle and Lechman will go in with a rolling chopper to break up the stalks. They'll later come back with a chisel plow pass and finishing operation. Other than that, their entire rotation - irrigation and dryland - is under a no-till program.
For weed control in sunflower, they'll apply an early May burndown, followed by a preplant tankmix of Spartan and Prowl H20. (They bought their '05 Spartan well in advance, so had a sufficient supply on hand in that product-short season.) That's it - except for spots where volunteer corn requires treatment with a grass herbicide.
Bauerle and Lechman band most of their corn and sunflower fertilizer needs at planting for two reasons: (1) to eliminate a field pass and (2) to leave intact as much wheat residue as possible. "We used to knife in anhydrous on all our corn, into the wheat stubble," Lechman says. "But that breaks down the straw too much and you lose too much residue. Putting it on with the planter has worked well the past couple years." For irrigated 'flowers, they've also applied a minor amount through the sprinkler at about the four- to six-leaf stage.
Of the 4.5 inches of water applied to their '04 confection sunflower circle, a half-inch early on with the fertilizer and then about four inches during the late-bud stage. Going into the season with a full soil profile certainly helped, as did some in-season rainfall. The results were
impressive: an average yield across those 120 acres of around 2,300, with 90% of the harvested seeds grading out as "plump."
Even with dryland confections, where they've reduced their seed drop to about 14,000 during this drought cycle, "we've been averaging 80 to 85% plump," Bauerle reports. Their yield goal on dryland is 1,300 to 1,400 pounds (compared to 2,000-plus on irrigated).
The bottom-line, Bauerle emphasizes, has been to save on water while maintaining strong yields and a quality product. He and Lechman believe their current program has definitely proven itself in that regard. Still, like most producers, they're looking to the future, anticipating ways they can be even more efficient. One possibility: skip rows. "I like what I've seen [of skip rows] in dryland corn, and we¹re going to try it in our irrigated sunflower [in 2006]," Bauerle advises. -- Don Lilleboe