Putting Planters to the Test
In 2007 John Smith put some popular sunflower planters to the test, evaluating their seed-spacing performance with confection sunflower seed. This past year, he did the same thing with oil-type ’flowers.
Smith, who is an agricultural engineer with the University of Nebraska at Scottsbluff, conducted tests on metering units and associated seed tubes from a Case IH 1200 series flat-plate system, a John Deere MaxEmerge vacuum planter, and a JD finger pickup series. The National Sunflower Association funded both his confection and oil sunflower studies in an effort to help enhance seed spacing accuracy in the nation’s sunflower crop.
Smith’s 2007 confection seed test results were summarized in the “Sunflower Planting Supplement” carried in the January 2008 issue of The Sunflower. (View the confection planting article.) He recently reported on his tests with oil-type sunflower seed at the 2009 NSA Research Forum.
Seed spacing accuracy with the various planter units was measured on the opto-electronic sensing test stand developed by Smith and his colleagues at the UN Panhandle Research & Extension Center. This test stand will track the exact point when each dropped seed passes through the sensor system, as well as where it passes through. The system software converts the “when” and “where” information to an actual distance between seeds. It senses the seed beneath the seed tube, at a point equating to the bottom of a field’s seed furrow. The test stand’s grease belt simultaneously provides an opportunity to visually evaluate seed spacing.
For the 2008 oilseed study, Smith used 9.0” as the targeted in-row spacing, with a standard ground speed of 4.5 miles per hour. Size 4 seeds were used exclusively (except when he was evaluating the effect of changes in seed size). Each run was replicated four times, with 500 continuous seeds per replication.
The following variables were addressed in the study, per the specific planter being tested: effect of field speed; best plate selection; sensitivity to vacuum adjustment; with/without graphite and talc; effect of seed size change; best settings for each seed size; effect of Cruiser® seed treatment; and effect of “worn” seed tubes.
The Nebraska ag engineer used three terms in categorizing the accuracy of seed spacing performance. They are:
• “CP3” — This indicates the percentage of seeds with excellent spacing, i.e., within a half inch of the 9.0” target spacing. A CP3 rating of 90% would be considered a perfect-looking spacing. A 70% CP3 would still be quite good, whereas one closer to 40% would be irregular.
• “Wide” Spacings — This is the percentage of spacings greater than 13.5”, i.e., typically thought of as “skips.” Preferably, this category should be no more than 3-5%.
• “Close” Spacings — This refers to the percentage of spacings less than 4.5”, i.e., “doubles.” The preference here is to keep such spacings below 3%.
Smith’s findings for the tested planters’ performance can be summarized as follows:
Case IH 1200 Series — Seed spacing for oil-type sunflower seeds with this unit can be generally described as excellent. Higher field speed does affect the CP3 percentage, as is also the case with the other two planters. It’s important to set the singulator correctly, while the vacuum setting with the 1200 Series is relatively insensitive. The data show that changing seed size without changing plates or settings does, as would be expected, impact accuracy. Also, using worn seed tubes with their roughened interiors will significantly lower the seed spacing accuracy. Using a mix of talc and graphite will help lubricate planter parts and benefit seed flow. Cruiser seed treatment did not have an effect on spacing accuracy with this planter.
Deere (MaxEmerge) Vacuum Planter —The flat plate A52391 is not a viable option for oil-type sunflower, since the plate holes are too large and seeds tend to plug. (This plate does work well with the larger confection seeds.) Cell plate H136478 and flat plate A52390 do work with oil sunflower; but the doubles eliminator on the flat plate system provides more options to reduce skips and doubles. The vacuum setting with the MaxEmerge is an important component of minimizing skips and doubles. As with the Case IH unit, replacing worn seed tubes is important for spacing consistency.
Smith also compared the Deere cell plate (H136478) with two plates from Precision Planting. Both of the Precision Planting plates had significantly higher CP3 ratings than the Deere plate.
Overall, Smith rates the popular Deere vacuum planter as “good” in terms of spacing accuracy with oil-type sunflower seeds.
Deere Finger Pickup Planter — This planter is questionable, in Smith’s view, in terms of its spacing accuracy with sunflower. Its CP3 rating on both #3 and #4 seed was improved by using the Precision Planting short-finger option (see results at left). A slower field speed (3.0 mph) resulted in a significantly lower CP3 rating than did speeds of 4.5 or 6.0 mph. The use of talc and graphite provided an improvement in the CP3 rating, but had no effect on wide or close spacing performance.
What, in Smith’s view, is the number-one item that would provide a significant improvement in seed spacing performance with these planters with sunflower?
“It would be the use of a planter monitor that will provide the operator with seed spacing information between individual seeds,” he states. “Your standard monitors will not do that. They’ll give you average seed spacings, but not individual.”
Without such a monitor, “how can you know whether you have the right plate, the right vacuum, the right singulator adjustment before you go to the field,” he asks, “let alone getting into the field and discovering things are not what they should be?”
The only current planter monitor Smith is aware of that will provide this real-time individual seed spacing information is the 20/20 Seed Sense™ unit sold by Precision Planting, Inc. — Don Lilleboe
Watch video clips of John Smith discuss his test results.
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