Compaction Concerns Contribute to Applicator Design
Application equipment manufacturers are very aware of increasing concerns over compaction. Meeting those concerns has contributed significantly to design considerations, optional features, tire selection and even uses of fleet management software. Case IH, Miller St. Nazianz, Hagie and AGCO can all point to design changes they have made in response to these concerns.
"Producers are looking to get more out of every acre," said Mark Burns, Case IH. "Compaction is detrimental to percolation of water and nutrients into the soil. Anything we can do to help with that is at the forefront of the producer's mind."
Anything that can be done to reduce compaction is positive, agreed Mark Jeschke, agronomy research manager, DuPont Pioneer. "Compaction is especially damaging in a crop like corn with its fibrous root system that can't penetrate compacted zones," he said. "This is especially evident in drought conditions like we experienced this past summer if soil is already compacted from the previous season."
Ironically, the excessively dry season may have helped resolve some compaction as deep cracks opened in the soil. Those limited areas with fall rains may have seen some benefit there.
Regardless, even in the best of conditions, compaction remains a concern. Jeschke pointed to the ever larger and heavier equipment being used by growers, as well as custom applicators, as driving the issue.
PHOTO COURTESY OF CASE IHThe tank in the middle and the engine in the rear is a solution to having equal amounts of weight on all four tires used by equipment manufacturers. Field application equipment doesn't get much bigger than the Nitro Series 5400 from Miller, especially when it's equipped with a 1,600-gallon tank. Taking potential compaction into account was central to its design, said Tim Criddle, director of marketing, Miller St. Nazianz. He noted the company's recent Voice of the Customer surveys with field interviews made clear the importance of reducing compaction.
"More and more people are truly cognizant of the yield potential that can be unlocked in part by reducing compaction," said Criddle. "We realized early on that we needed to balance the weight evenly to reduce front or rear bias. We spent a tremendous amount of time and expense in developing the 4,000 series, and now the 5,000 series, so that every component was placed where needed to give us close to a 50/50 weight distribution whether the tank was full, half-full or empty."
EVENING WEIGHT DISTRIBUTION
Even weight distribution is the Holy Grail for applicator manufacturers. Several manufacturers claim one or more models/configurations within three to four percent or less of even weight distribution. As tank volume and booms increase in size and weight on a given model, the variance tends to increase as well. A critical point in evaluating distribution is that it stays relatively the same as the tank goes from full to empty.
PHOTO COURTESY OF AGCOAll-wheel steering offered by manufacturers keeps front and rear wheels traveling in the same track for compacting soil in only one wheel track. For Case IH, Hagie and Miller St. Nazianz, the road to less compaction led to a center-mounted tank with the cab at the front balancing the engine at the rear. From there, the three diverged with Case IH putting the boom to the rear and Hagie and Miller placing it at the front. Hagie's lightest weight sprayer utilizes two 500-gallon saddle tanks as part of its compaction reduction effort.
AGCO sought improved front and rear parity with its 2012 introductions by moving the front axle back a little more than 10 inches to put more weight over the front end. This, along with other changes, puts the front-to-rear weight distribution for the RG900 RoGator with a 90-foot boom in that plus or minus three percent ratio.
Distributing each wheel's weight over the greatest footprint is also important, suggested Paul Haefner, business development manager for the Northwestern U.S., AGCO Application Equipment. "It is best to minimize compaction where you can," he said. "One way is with tire pressure and ground contact area. With the VF tire from Michelin, we can run at 34 pounds versus 62 pounds pressure, giving us a wider, longer footprint within the row, yet running safely on the road."
Burns noted that an increasing number of customers are ordering Case IH applicators with two sets of tires. "They like wider tires for spring application when soils are wetter and there is more concern over compaction, but less concern over staying between rows," he said. "They switch over to narrower, conventional row-crop size tires later in the season."
Compaction concerns are also contributing to rapid adoption of all-wheel steering, noted Criddle. "We already had the tightest turning radius in the industry, but our customers said that didn't translate into minimizing compaction," he said. "They wanted a machine that would track rear to front to truly minimize compaction."
REDUCING CROP DAMAGE
When AGCO first introduced all-wheel steering, GatorTrak, it found a niche market in cotton production states. Now interest in reducing compaction and crop damage at the headlands is driving demand in the Corn Belt as well.
"If an operator can show his customers that he is doing less damage in the fields and increasing production in the headlands, the dollars add up pretty quickly, and that is before you bring in reduced compaction," said Haefner. "Eighty percent of compaction happens when you run the first tire across the ground. If you can keep following tires in the same track, it has a significant reduction on additional compaction."
Amber Kohlhaas, brand manager, Hagie, pointed to the multiple reductions in crop damage, ground disturbance and soil compaction with all-wheel steering, currently being purchased as an option by 75 percent of STS buyers. "Our All Wheel Steer (AWS) system reduces our turning radius and increases the active speed range by limiting how far the rear wheels turn at higher speeds," she said. "AWS also improves tracking on contours and in wide turns on end rows."
If matching tracks in a given pass is important, that benefit is multiplied when each pass throughout the season follows the same track. Precision steering and field mapping offer customers the benefits of virtual tramlines in the crop. AGCO customers using the AgCommand fleet management system are taking this a step further, said Haefner.
"Some larger fleet owners are looking back at their equipment after the season and using AgCommand to better manage equipment in a given area for a given customer group," he said. "They can look at the customers and assign uniform equipment for herbicide and insecticide application that also match a grower's tracks."
Controlled traffic in the field is important, agreed Jeschke. He added that it is one of many compaction reduction tools that growers and their input suppliers can use to enhance crop potential. "Nobody likes to see compaction, but it is something you have to deal with the best you can," he said.