As tillage practices and equipment evolve, it’s smart to occasionally evaluate your equipment choices. This video compares the differences between a Frontier VT1712 vertical tillage tool (US CA) and a Frontier DH1612 disk harrow (US CA). These two machines have the same working width, but offer different disk types and very different approaches to tillage practice.
We’ll be using a John Deere 6120E Utility Tractor (US CA) for both. It delivers 120 engine horsepower (89.5 kW) and includes the standard 12F/12R PowrReverser transmission
We’ve also added 1400 pounds (635 kg) of weight to the front of our tractor and 240 pounds (109 kg) to each rear wheel. That’s so we have sufficient weight on the tractor to help prevent rear wheel slippage, or power hop.
We conducted this comparison in Columbus, Mississippi in October, 2016, working in soybean residue. It hadn’t rained here in 8 weeks, and as you’ll be able to see, it’s dry, it’s dusty, and the ground is pretty hard. But those aren’t uncommon conditions in this part of the country for this time of year.
First, let’s compare these two tillage tools.
We began with the Frontier DH1612 disk harrow.
This disk has a working width of 12 feet (3.66 m) and is designed to size residue and incorporate it by tilling up to 5-inches (12.7 cm) deep. We’ve set the front and rear gang angles at 25-degrees and 24-degrees respectively. And we used notched blades in both the front and rear gangs. You could use spherical blades, or a combination of the two, depending on your situation.
We also added a rolling basket that’s designed to break up clods and leave a smooth, level surface.
The VT1712 Vertical Tillage Tool also has a working width of 12 feet (3.66 m) and is designed specifically for vertical tillage. It will also size residue and fracture the soil, but only to a depth of 1 – 3 inches (2.5-7.6 cm). We set its gang angles at 3-degrees and used straight fluted blades, so the residue stays on or near the surface. This tool also has a spiral-blade rolling basket on the rear.
Both tillage tools offer adjustable gang angles, rear-mounted rolling baskets, and blade-type options.
So why would you choose one over the other?
The answer depends on your soil profile and your long-term approach to tillage practice.
If you live in an area with a relatively thin layer of topsoil like the one here in Mississippi, then you have to make decisions differently than someone who lives in an area with 6, 8, even 12 or more inches (15.2, 20.3, 30.5 cm) of topsoil.
These two environments tend to experience different annual moisture levels. Areas with thinner topsoil tend be dryer overall. The average crop yields from these two environments can also be quite different. But many of the input costs can actually be similar. Seed, fertilizer, chemicals, fuel – these costs tend to be similar on a per acre basis.
So if you live in an area that is dryer, has thinner topsoil, and lower average yields, a tillage practice that only penetrates a few inches, like vertical tillage, might be the best choice. It will size the residue while only fracturing the soil 1 – 3 inches (2.5-7.6 cm deep. The residue decomposes on or near the surface, helping prevent wind erosion, while leaving a smooth level seedbed. In this way you maximize the protection of your valuable topsoil while helping the soil absorb and retain moisture and nutrients. And you’d do it all in one pass.
If your property has a much deeper layer of topsoil, then you might prefer a type of disk like the DH16 Series. The thicker layer of topsoil allows you to disk deeper in your first pass, incorporating the sized residue deeper into the soil, along with weed roots and seeds, helping kill the seeds while the decomposing residue adds nutrients back into the soil.
Over time, this intensive tillage will create a horizontal layer of densely packed soil, or hard pan, which will form at the bottom of your disking depth. As time goes by, this high-density layer will begin restricting the ability of plant roots to penetrate deeply into the soil. That lowers their ability to access moisture and nutrients, forcing each plant to compete with its neighbor, ultimately lowering yields. There are ways to break up the hard pan using additional equipment, which naturally require additional passes over your field.
You should also be aware that the deeper you till, the more tractor power you’ll need.
Soil. Cost. And results.
The DH1612 disk harrow and the VT1712 vertical tillage tool produce different results you can actually see. The DH1612 tills deeper, more aggressively fracturing the soil and incorporating the residue. The VT1712, with much less severe gang angles, and set to a depth of only 2-inches (5.1 cm), has sized the residue nicely, but leaves it virtually on the surface.
So which one of these tillage tools might be right for you? That depends on your soil profile and your current cost of operation including fuel, seed, fertilizer, and chemicals. Because ultimately, the right answer for you depends on which tillage practice can best improve and maintain your field’s crop-producing ability for the long term.
Frontier has over 600 implements that are available only from your John Deere dealer, the place to go for advice and equipment.
So remember, for implements that help turn your tractor into the workhorse it was built to be, think Frontier and your John Deere dealer.
And always remember to read the Operator’s Manual before operating any piece of equipment, and follow all operating and safety instructions.
How to adjust and operate the VT17 Series vertical tillage equipment
Why vertical tillage might be right for you
Why & When To Use A Cultipacker