Corn growers who've tried Liberty Link corn like what they see - in the field and the bin.
Weed control with Liberty, alone or in combination with other herbicides, has been good to excellent, they report. And the trait, owned by AgrEvo, is available from most seed companies in some of their best-yielding hybrids. Some companies have stacked the Liberty Link gene with Bt, giving their hybrids protection from European corn borers as well.
There have been some disappointments, but failures have been few and far between. Most can be traced back to rate cutting to save money.
Liberty comes with its own drift retardant, so growers don't have to pay extra to reduce the risk of drift damage to nearby crops and non-crop plants (like the neighbor's rose bushes).
But there's a potential downside, too. AgrEvo has no seed technology fee, but some seed companies do, which can add cost.
Also, if you use full label rates or need a second application, costs can mount. When you compare two applications, for example, of Liberty with herbicide programs centered around lower-cost herbicides like atrazine, Banvel and 2,4-D.
Todd Gingrich, Ottumwa, IA, figures the Liberty program he used this year was quite economical, however. He planted 800 acres of Liberty Link corn and also custom-applied Liberty on 600 acres for neighbors.
"We applied a quarter pound of atrazine preplant on 1,100 acres. The rest received no preplant or pre-emergence herbicide," he reports.
He got the best weed control where atrazine was followed by a half rate of Bicep when the corn was from spike to 2" tall, followed by 16 oz/acre of Liberty mixed with 2.5 lbs of ammonium sulfate.
"That was the ideal combination this year," Gingrich declares. "No weeds escaped at all."
The cost of that program, including three sprayer trips, totaled $23/acre. "A full rate of Bicep or Harness would put you in that range, and you'd still need an additional chemical to give you complete control of both grass and broadleaf weeds," he believes.
Steve Swackhammer, West Des Moines, IA, agrees. He no-tilled 725 acres of Liberty Link corn this year.
"We've tried a lot of herbicides," Swackhammer comments. "We'd been mixing up this and that in order to make a burndown, and then mixing other herbicides together in order to have an effective postemergence program. It was getting expensive.
"We've trimmed some of those costs by going to an atrazine- 2,4-D burndown. And one post-emergence application of Liberty gives us the weed control we were looking for without all the measuring and mixing of other herbicides."
When weeds were small, he used 20 oz/acre of Liberty. Where wet weather kept him out of fields and weeds got taller, he applied 28 oz/acre.
"The burndown costs about $9 an acre, and 20 oz of Liberty runs right at $17, so most of my weed control was under $30 an acre," Swackhammer reports. "The higher rate of Liberty cost right at $23 an acre, so costs there were still under $35.
"I figure anytime I get by in no-till corn for less than $40, I'm staying within my budget." His previous postemergence herbicide program for no-till corn left him with a lot of escapes last year.
Swackhammer says Liberty is reliable and has a wider application window than most post-emergence herbicides or herbicide combinations he's used.
"It gets weeds of all different sizes. To get taller weeds, all you have to do is hike the rate."