That Was the Question at the Virginia No-Till Alliance Conference
HARRISONBURG, Va. — If you’d come to the fifth annual Virginia No-Till Alliance annual conference searching for a cut-and-dried answer to whether vertical tillage might benefit the yield and profitability of your no-till fields, you were going to be disappointed.
“Everybody has different soils, different conditions and different needs,” said Gerald Garber, a Rockingham County farmer who spoke briefly about his experiences with vertical tillage on a panel during the conference.
In other words: Maybe vertical tillage is a good idea, and maybe it’s not.
The practice of vertical tillage — using specialized equipment to till no deeper than several inches with limited horizontal movement of the soil — has become the subject of some debate within no-till circles in recent years. Matt Yancey, a Rockingham County Extension agent who helped organize the event, estimated that about 30 percent of no-till farmers in the region have begun using vertical tillage to some extent.
Vertical tillage can speed decomposition of crop residue by partially incorporating it into the soil, smooth fields (particularly after they have been grazed by cattle), and help prepare an even, level seedbed for planting. Some farmers also use the practice to incorporate small grain seed after broadcasting it on a field.
And in the aftermath of last year’s widespread slug problems — the worst in recent memory — reducing crop residue left on fields with vertical tillage has been suggested as a way to reduce slug populations by limiting their habitat.
Bobby Clark, an Extension agent from Shenandoah County who has focused on slug control on no-till fields, spoke on the subject at the conference, along with Joanne Whalen, a pest management specialist from the University of Delaware.
While vertical tillage may help combat slugs, a farmer could pay a steep price in collateral earthworm damage, argued Dave Wolfskill, a Berks County, Pa., dairy farmer who also spoke.
Wolfskill, who has run a 100-percent no-till program since the late 1980s, talked at length about how a healthy population of earthworms improves soil structure, aeration, water infiltration and fertility. He also showed slides taken in his fields that demonstrate how quickly earthworms themselves can incorporate crop residue into the soil.
Using vertical tillage equipment to accomplish the same task, he said, can undo years of work worms have done to improve a field.
Wolfskill’s earthworms have helped him put up some impressive numbers: in 2008, he was national corn grain champion in the non-irrigated, no-till category, with a yield of 297 bushels per acre. Last year, he took second with a yield of 307 bushels per acre.
He also emphasized using a properly calibrated and well-maintained planter to establish a healthy stand. Row cleaners on the front of the planter, he said, are the feature he recommends most to improve a farmer’s success with no-till planting, because they make it much easier to plant seeds at a uniform depth.
The first speaker of the day was DeAnn Presley, a soil management specialist from Kansas State University, who presented results of field trials conducted in Kansas to compare the effects of different vertical tillage implements to no-tilled fields. While her study concluded that vertical tillage didn’t appear to reduce the health of a no-till field’s soil, it didn’t appear to really help it, either.
If planting through heavy crop residue is a problem, she said, vertical tillage could be an answer. And she agreed with a laugh when someone in the audience pointed out that it might be best to invest in a better planter rather than a fancy new vertical tillage implement. Everything always depends.<\c> Photo by Andrew Jenner
David Wolfskill, a Berks County, Pa., dairy farmer, reacts to an audience question during his presentation at the Virginia No-Till Alliance Conference. Using 100 percent no-till methods, Wolfskill has achieved corn yields of more than 300 bushels per acre.