Article Archives
Flooding the Field

Monday, November 25, 2019
filed under: Irrigation/Water Use

Tim Trupp inspects a 2019 furrow-irrigated sunflower field on the farm he and his brothers operate at Prospect Valley, Colorado.
Recently, the Trupp brothers — Tim, Barry and Kerry — know full well the upside of center-pivot irrigation.  There’s the increased water-use efficiency . . . the decreased labor requirements . . . and the overall ability to manage your water more precisely.  They also are well aware of the continuing trend away from flood irrigation and toward overhead sprinkler units.

Still, the Trupp (pronounced ‘troop’) brothers remain among that segment of east central Colorado producers who still “lay the pipe,” irrigating their cropland via the furrow with siphon tubes.  


In a word, logistics.  The sizes, shapes and locations of their Prospect Valley fields simply do not lend themselves to center pivots.  “We’d lose irrigated acres,” Tim states.  “We have corners, triangles.  Houses are in the ‘wrong’ spot.  On a couple farms, we have power line poles.”
All of the Trupp row-crop acreage is irrigated: corn, pinto beans, sunflower — and, in 2019, even some hemp.  Through the years, they’ve worked to optimize their irrigating efficiency to the degree possible, utilizing surge valves on some fields instead of siphon tubes, for example, and applying PAM (polyacrylamide) as a flocculating agent to help minimize soil runoff from the rows.  
Most runoff from their fields ends up in holding ponds, so gets reused.  “Some of the ponds are on different fields, but they catch the tail water,” Tim notes.  “If we don’t have a pond, the ‘guy down the road’ has one.  So very seldom does any runoff not get recycled.”
What about water use volume?  Aren’t they restricted in supply — especially in drier years?  “It is basically a matter of water availability,” Tim concurs. “This year, we had a lot because there’s a lot in the mountains.  So, for example, (a nearby sunflower) field got irrigated four times this season.  In drier years, it’s maybe just once or twice, given how much water is available.”
The Trupps, whose farms are part of the Lost Creek closed basin, have wells in addition to canal water.  “If we just pumped the wells, we can only cover so much.  Say a well is pumping 1,000 gpm.  We can get around (all the acreage) — but not as fast as we should,” Tim says.  “So we add canal water to cover more ground in a timely fashion.”   
The Trupps have been growing confection sunflower for 20-plus years, contracting with Red River Commodities.  This year, they planted 300 acres of confections.  
Their furrow-irrigated ’flowers are in 30” rows, with alternating rows carrying the water.  In some years they’ll need to “irrigate up” (pre-water); but with a wet spring, they didn’t need to do so in 2019.  “We irrigated at around the 18” growth stage to give them a good start,” Tim relates. “Then, of course, also when they’re heading and filling seed.”
Typically, the longevity of each irrigation set is 12 hours.  The length of the furrow dictates tube diameter. “If we use a 2” tube, for instance, it’s because we have a half-mile run,” Trupp notes.  “Where it has a quarter mile, we’ll use tubes that are either 1.5” or 1.25” in diameter, irrigating every other row.”  Should the water not be moving down the row quickly enough, they’ll sometimes place a second tube in the row to increase flow.
“You want to be done in 12 hours, but you don’t want to run water out the bottom end,” Tim observes.  So it’s a balancing act of sorts: moving sufficient water to the bottom of the field without over-irrigating.  Having done it for decades, the Trupp brothers have pretty well mastered the process.
Some of the Trupp sunflower goes in on wheat stubble.  They’ll rip 13-14” inches deep with a Blu-Jet unit; “then we’ll apply the chemical with a field cultivator and work it in right away,” Tim notes.  Where the sunflower follows corn, they’ll plow, float and roller harrow prior to planting.
“In a year where we know we’re going to have to irrigate, we’ll go out and bed it,” Trump continues.  “We’ll make the furrows first and plant on top.  But in a year where there’s moisture, we just plant on flat ground.”
Their sunflower yield goal ranges from 2,500 to 3,500 lbs/ac per year, and they’re achieved as high as 3,600-3,800 lbs.  Insects — particularly head moth and seed weevil —require treatment virtually every year.  But Tim says their main challenge in any given season is satisfactory seed emergence — even with adequate spring soil moisture.  Seed drop is 16,000, with expectation of a harvest population of 12, -13,000 (though this year it was significantly higher).  They’ll typically plant 2.0 to 2.5” deep, knowing that if they go shallower, they’ll need to irrigate up.  “So we try to get them to moisture unless it’s way too deep,” Tim explains.  
While siphon tubes will likely remain a reality on at least some of the Trupp fields for years to come, Tim says there are a couple farms where they are considering installation of center pivots.                       
“We’re all getting older, so carrying those tubes isn’t much fun,” he quips with a smile.
 — Don Lilleboe    
return to top of page

   More about Sunflower ►