This year AGCO has been looking into the different variables that affect yield when it comes to equipment – variables that you may see on your farm.
Specifically AGCO looked at the planter and the interaction between equipment, soil and seed. The premise of the plots, and what was called Crop Tour, was not to compare AGCO equipment against competitive equipment, but to compare the yield effect of a planter that is set and operated correctly versus one that is not set correctly. The same planter, when equipped, maintained and operated well, can increase yields in corn by double digits compared to the exact same planter equipped, maintained and operated poorly. When it comes to planting, its all about setting the stage for every seed to produce a good plant, that produces a good ear. The question that we as growers want to ask ourselves is what is our ear count and how does my ear count compare to my plant count?
The number of ears and the size of the ears is what drives yield. A planter can make errors that fall into four categories:
- Errors that cause erratic emergence.
- Errors that create compaction around the seed.
- Errors that cause skips and multiples.
- Errors with population target.
AGCO looked at some of these errors this year in the Crop Tour, and the results are amazing, just seeing the difference between getting those five things correct versus incorrect:
Emergence and compaction
In each of the Crop Tour plots, three passes were made with regards to downforce–too light, causing shallow planted seed; too heavy, causing compaction, and just right; ensuring the seed environment is perfect.
Why does too little downforce cause a problem?
If the row unit does not have enough force applied to it and it does not maintain depth, the shallow seeds could be planted into inconsistent soil moisture. The seeds need moisture to germinate, and so a seed in drier soil will take longer to germinate and emerge. Plants that emerge more than 36 hours after the rest of the field will see a significant loss in ear size and will potentially not have a harvestable ear.
Why does too much downforce cause a problem?
Too much downforce ensures that all seeds are planted at the correct depth, however the excess weight that is not needed for the disk openers to penetrate the ground is carried on the gauge wheels. A few hundred pounds on the gauge wheels will put excess pressure soil below them, causing compaction. Compaction reduces the oxygen in the soil, also prevents water from infiltrating and also causes the roots to have to turn and become smaller to get through those tight pore spaces, causing a runt plant a subsequent loss of ear size.
Should you have a correct downforce break just like too little and too much?
The correct amount of downforce will result in seeds planted at the correct depth but with lower amounts of gauge wheel weight which eliminate compaction. With correct downforce, plants emerge uniformly and roots develop well in an ideal seed environment.
The tests in the crop tour plot showed some interesting results. First, where the planter was set with too light of downforce, gauge wheels sometimes lost ground contact causing inconsistently placed seeds and an average of 20 bushels per acre lost across six locations compared to optimum downforce.
Where the planter was set to run excess downforce, we also saw a yield loss in every plot. The amount of gauge wheel weight averages 187 pounds. This is the weight that the row unit was carrying above and beyond what was needed to maintain depth. On average, the heavy pass was six bushels lower than plots with optimum downforce.
The correct downforce pass showed that ground contact was 100%, just as in the heavy pass; however, the average gauge wheel weight was 66 pounds less, at only 121 pounds of weight on the gauge wheels. The correct downforce pass created more uniform emergence, stronger more consistent plants and higher corn yields than the heavy or light pass in every location.
The weigh pin on the planter allowed for the gauge wheel weight to be measured, and with the automated control system, a consistent gauge wheel weight was maintained. The operator selected a target gauge wheel weight, and if the weigh pin measured above that weight, the hydraulic cylinder applied less force; if the pin measured below the operator’s target, more force was applied. The force was automatically being adjusted multiple times per second, each row adjusting individually, so that the weight carried on the gauge wheels of each row was consistent. The accompanying map shows the gauge wheel weight as a result of DeltaForce control.
A downforce system that is able to measure gauge wheel weight and adjust to changing soil conditions on-the-go can provide consistent emergence and a reduction in compaction.
Singulation is the measurement of planting one seed at a time, rather than planting a skip or a multiple. In order to make a comparison, plots were planted using seed disks that had two holes plugged, and two extra holes were drilled, creating skips and doubles while maintaining the target population.
The results of this study were also intriguing. On average, across the seven locations, there was a 8.7 bu./ac. loss in yield from poor singulation. This is pretty significant.
During the Crop Tour, a question that most of the producers were asked was “What is the singulation percentage of your current planter?” Many producers did not know, and some said it was in the mid-90s, with others saying their planter was above 99% when it came to singulation. The 8.7 bu./ac. loss came from 91.4% singulation when compared to 99.3% singulation on the correct rows. The result was about a 1.1 bushel per acre yield loss per percent in singulation reduction. An increase from 96% or 97% singulation to 99%+ on the 9800VE Series planter can pay big dividends on your farm. The 9800VE Series uses a vSet meter that requires no adjustments to maintain above 99% singulation in all seed sizes.
The importance of meter accuracy means uniformity in seed singulation, uniformity of seed spacing and accuracy of plant population.
• One double planting of seeds per 1/1,000 of an acre over a 17’ 5” row length can equal a 2.8 bushel loss in yield.
• Crop Tour found 1.1 bushel/acre loss per percent loss in seed singulation in 2016 but multi-year research indicates that a one percent loss in seed can equal a two to 2.5 bushel per acre yield loss.
The AGCO Crop Tour also looked at emergence in another way–planting depth. Planters were set to plant from one inch to 3.5 inches in half-inch increments. Too shallow of a planting depth can put seeds at risk for late emergence due to not having all of them in consistent moisture. In most fields, the moisture line varies; for example, if the moisture line varies from two inches deep to one inch deep, and you set the planter to plant at 1.5 or 1.75 inches, there will be some seeds in drier soil. Getting below the deepest spot in the moisture line will place every seed in consistent moisture. Planting shallower than 1.5 inches also results in poor nodal root formation, making it difficult for the plant to access moisture and nutrients. Plant too deep, and there is the potential for poor germination due to cooler soil temperatures and delays in emergence and seedling vigor from the plant having to use stored seed energy to produce a longer mesoctyl.
In the seven plots, either two inches or 2.5 inches yielded the highest. Planting shallower than 1.5 inches resulted in a 15 bushel per acre yield loss across seven sites. Planting deeper than 3 inches resulted in a 36 bushel per acre yield loss. The sweet spot was between 1.5 inches and 3 inches in 2016.
Overall, you want to select a depth that places every seed in moisture. Some farmers believe that a seed planted closer to the soil surface will emerge faster; however, that comes with the risk of poor nodal root formation and can lead to inconsistent emergence if soil moisture is limited. Getting the correct planting depth is key.
Population and Spacing
What happens to the population on each row of a planter as it goes around a curve? Well, all the rows drop the same number of seeds because the shaft turning the meters is turning the same speed, however the inside rows of the planter slow down, and the outside speeds up, making the actual population incorrect. At the Edgewood, Iowa plot, this was showcased around a very tight curve. The planter was run to plant as a planter with a hex shaft would around a curve, and you can see the results in the map below; a wide population variance.
In this study, we harvested the ears from 1/1,000 of an acre from the inside of the curve, the outside of the curve and the middle of the curve. See the pictures below.
Obviously on the inside of the curve there was an error in population, which caused the plants to be spaced too closely, which led to a 51.5 bu./acre yield loss. On the outside of the curve, there was also a yield loss because there was a population error also, with only 21 ears, resulting in a 69.5 bu./acre loss. The center had the correct spacing, correct population and a large gain in yield. The 9800VE Series planter corrects this issue because it uses the vDrive system, which allows the meter on each row to turn whatever speed it needs in order to have the correct population on that row. So along with removing complex drive systems, the vDrive system adjusts the population on each row to match the speed of the row, so all rows have a correct population. The vDrive system also allows for individual row control of swath as well as variable rate prescription changes to be made on a per row basis rather than on a section basis.
Overall, the 2016 Crop Tour was a very educational event and the agronomic plot work done by AGCO showed very interesting results. It is obvious that correct planting will increase yield, however these plots really put some yield numbers to the cost of planting errors.
- The ability to accurately measure and control downforce on each individual row is important to allow for:
- Field variation in soil texture and bulk density.
- Changes in seed depth settings.
- Different tillage systems.
- Differences across the width of the planter, especially in central fill planters.
- In 2016, White Planters™ 9800VE Series planters that were part of Crop Tour planted over 6,000 acres of corn and averaged 99.6% singulation accuracy.
- Seed singulation matters: Across six sites* there was an eight bushel per acre yield advantage at 99.3% seed spacing accuracy compared to 91.4% seed spacing accuracy.
- Optimized downforce improved yields on average across six sites by 20 bushels per acre compared to too light and by six bushels per acre compared to too heavy.
- Planting depths from 1.5 to 3 inches deep allowed for uniform emergence and adequate nodal root formation. Planting just ½ inch shallower than the 1.5 inch minimum suggested planting depth resulted in a 15 bushel per acre yield loss on average across five Crop Tour location sites.
- Our hand harvest done in Iowa that showed the yield loss that happens with a traditional drive system around a curve.
- With $4 per bushel corn DeltaForce will increase returns by a minimum of $24 per acre (correct versus excess). DeltaForce on a 12 row planter will pay for itself in approximately the first 675 acres of use.
- At $4/bu. corn accurate seed spacing (vSet/vDrive) will increase returns by approximately $35 per acre (control versus poor singulation). vSet meters and vDrive will pay for themselves in approximately 582 acres of use.
- White Planters has the most accurate depth control system in the industry. Planting depth matters. As little as a half inch too shallow or two deep can cause losses up to $160-$200 per acre.
* Amboy, IN light plot removed from light average due to unrealistically low downforce at planting.
2016 Crop Tour Report for all plots