Farm Journal Test Plots continue to study starter
Starter fertilizer is a game of inches. That’s how precise of a role placement plays in feeding a crop early in its development.
In the Farm Journal Test Plots, Farm Journal Field Agronomists Ken Ferrie and Missy Bauer conduct independent field demonstrations to learn more about starter fertilizer’s role in increasing yields.
"Many factors come into play, including starter rates, products and placement," Ferrie says. "We’ve done starter test plots for more than 25 years, but every year teaches us more."
In the past, Ferrie has conducted extensive plots looking at starter product blends and attachments. (See "Starter Test Plot Roundup" in the February 2013 issue.)
"When we discuss timing and placement of nutrients, there’s a hierarchy in the decision-making," Ferrie explains. "Timing is determined by the environment—when does the plant need the nutrients to be kept happy all season long? Then timing sets the scene for placement. Placement strategies dictate the source."
There are two keys to placement: Put the nutrients where the plant can access them and never disrupt the seed itself.
"Based on our past studies, on average, we could expect a 7 bu. to 10 bu. response to starter placed to the side and below the seed and a 3 bu. to 5 bu. response to in-furrow application," Ferrie explains.
With tests in central Illinois and southern Michigan (pictured) in 30" and twin-row corn, the Farm Journal Field Agronomists validated starter rates should be determined by per foot of row for maximum yields.
The in-furrow yield bump results from the seed roots encountering the fertilizer very early. Because of the risk of starter burn, in-furrow rates must be limited to reduce the potential harm from putting too much salt around the seed, which could affect germination and ear count. Outside the furrow, a second fertilizer band to the side and below the seed is where farmers can increase rates and still reach the plant for early uptake of phosphorus.
Set the stage. Environment plays a big role. The cooler, wetter years often have a bigger response in early growth to starter fertilizer, phosphorus and placement.
"Once I know the environment, I think about timing," Ferrie says. "If planting into cool, wet conditions, a farmer might have trouble with phosphorus availability. In soils with low fertility or high pH, he or she might put most of their phosphate into a starter band to reduce
nutrient tie-up issues."
Once timing is nailed down, farmers should consider placement and source. Results from the 2012 placement study led Ferrie to drill down into dual placement with just two attachments. For 2013, Ferrie focused on learning more about placement and rates of dual placement of starter in-furrow and 2" to the side of the seed.
"The study looked at the effect of two starter placements and if there was a relay effect as the roots encountered the dual placements," Ferrie says.
The Illinois crew used a Kinze 8-row planter outfitted with the Schaffert Gen 2 fertilizer disk and Keeton seed firmers for the in-furrow application. The Schaffert attachment cuts a trench 2" away from the seed and uses an injection nozzle to apply fertilizer. (See inset photo, above.)
"We know that when we are placing starter fertilizer, inches matter," Ferrie says. "Phosphorus is not mobile like nitrogen, so you can’t dribble phosphorus on top of the surface for roots to be able to access it. Placing phosphorus close to the seed root with in-furrow pop up increases the level of phosphorus in the plant."
The Schaffert Gen 2 disk applied 10 gal. of 7-22-5 + 1 zinc. The in-furrow rate was 3 gal. of 10-34-0.
"I always advocate for farmers to maintain the proper phosphate-to-zinc balance. Usually, I would include chelated zinc in the in-furrow pop-up fertilizer. However, in the 2013 study, we did not, which I think has some effect on the pop-up only treatments."
In three of the five soil types in this field, there was no response or a negative response to the in-furrow treatment alone. All soil types had a positive reaction to the application made 2" to the side, ranging from 3 bu. to 12 bu. Most of the soil types and the field average had the greatest response to the dual positioning of starter—also called the relay effect.
"You can see a quick visual response when the in-furrow fertilizer kicks in, but unfortunately, that doesn’t always add up to more yield," Ferrie says. "When there’s banded fertilizer to the side, it’s like the fertilizer positions are handing off a baton so that the roots are finding the nutrients as they need it."
However, an in-furrow treatment could be more effective if mixed with an additive such as SFP’s Avail.
Bauer has found that to be the case in the cooler soils of her plots in the eastern Corn Belt.
To verify yield results, every Farm Journal Test Plot is harvested using calibrated yield monitors, and every bushel is weighed by grain carts with scales.
"We have found that in either in-furrow or 2"x2" placements, adding Avail to the starter helped increase early phosphorus uptake, increased early growth and in most cases advanced maturity," she says. "I’ve seen in-furrow fertilizer increase the phosphorus in the plant up to 50%."
Advancing the crop’s maturity can lead to lower grain moisture levels at harvest, which is advantageous most years in Michigan. She also reports that yield responses were 3 bu. to 5 bu. higher with Avail added.
Double up. Both agronomists ran starter test plots looking at in-furrow starter fertilizer rates applied to 30" and twin rows planted with a Great Plains Yield-Pro planter.
Ferrie’s location looked at starter response with 5 gal. applied in-furrow below the seed using the blade separator tube. "What we’ve learned in twin rows is that you have to measure your rates by per foot of row," Ferrie says. "So for example, 5 gal. in 30" rows means we apply 10 gal. in twins."
Bauer has also run starter row spacing studies in the eastern Corn Belt using a Great Plains Yield-Pro planter and its blade separator to apply in-furrow. Her work confirms the rate recommendation, but due to the sandier soils, her typical in-furrow rate for 30" corn is 3 gal. Using a 6-18-6 + zinc starter blend with Avail (Season Pass), Bauer led an effort to apply 3 gal. and 6 gal. in-furrow in both row spacings. In twin rows, it took the 6-gal. rate to have the affect of 3 gal. per foot of row.
"We saw dramatic, above-average responses to in-furrow fertilizer in 2013, which included up to a 17 bu. response in twin rows and a 16 bu. response in 30" rows. But, running the higher 6-gal. rate in the 30" rows did not increase yield because of starter burn," she says.
At the Illinois location, Ferrie’s crew took plant samples at V4 to measure early season growth. There was more than a 30% increase in the plant weight (see charts above) when pop-up fertilizer was applied.
"That’s what phosphorus does to the plant. It’s responsible for cell elongation and division, so the more phosphorous, the more plant growth," he explains. "What you see aboveground, you see belowground with roots."
A hungry crop. In addition to placement, Bauer reminds farmers to evaluate the nutrients and micronutrients provided in their starter choice, including nitrogen, phosphorus and zinc.
"With high uptake of phosphorus, plants reduce their uptake of zinc, so applying a chelated zinc will fight that potential deficiency," she explains. "Farmers should really pay attention to the source of zinc. It’s important to have a chelated zinc source rather than an ammoniated product, especially in-furrow."
In 2013, Bauer launched a study to evaluate the effects of adding sulfur to starter. With placement 2" to the side and 2" below the seed, this plot looked at applying a rate of ammonium thiosulfate (ATS) at 8.5 lb. of sulfur per acre.
"In the first-year results, we did not see a yield response," she says. "This field had 150 lb. of broadcast ammonium sulfate (AMS 12-00-24S) applied, so perhaps it was an environment that needed more sulfur."
These early observations reinforce how important knowing the environment can be for starter application. Bauer plans to continue to evaluate the role of sulfur in starter in 2014.
When and where. To help farmers weigh the potential benefits and risks of using starter, the Farm Journal Field Agronomists share the following recommendations.
- Prioritize corn-on-corn fields and those with low phosphorus levels in the soil test.
- If farmers have a high carbon penalty, pop-up fertilizer will not help supply the nitrogen demanded in that environment.
- Avoid cutting phosphorous levels in starter fertilizer if soil test levels are low to medium.
- As rough estimates, 10 gal. of 7-22-5 could increase your fertility cost per acre by $12. The in-furrow rates of 3 gal. of 10-34-0 could increase fertility costs per acre by $6.
- Adding pop up to a starter program can lead to an early season response with more plant growth, advancing maturity to an earlier pollination period and quicker drydown at harvest.
"We can use starter as a tool to keep plants growing in cold soils. But be aware: When you change maturity, you may move it into the wrong week to pollinate. That’s a possibility and a reality, just like picking the right week to plant corn," Ferrie says.
- Lessons learned with dual placement verify the pass-the-baton response.
"In our studies, high rates of starter 2" to the side and below the seed have beat pop up alone. If you had to choose one, you’ll get a more consistent response from the higher rate. Then, you put the two together. It looks like a synergistic effect," he says.
- There is always a risk when putting starter fertilizer near the seed, especially in dry conditions and on sandy soils.
Don’t put starter on the seed if severe pericarp damage is more than 6%, advise the Farm Journal Field Agronomists. Seed with severe pericarp damage has a tear in the embryo axis. This doesn’t mean there’s a problem with the seed and its performance, but rather there’s more risk applying fertilizer close to the seed because of starter burn.
- Seed quality is a factor that must be considered when applying starter.
"In 2013, we saw more issues than we had in a while with samples returning with severe pericarp damage," Ferrie says. He regularly verifies seed quality with test plot samples, as well as samples from his farmer customers. Most seed labs can provide pericarp damage tests if farmers are interested in knowing more about their seed quality.
In his plots referenced in this story, the severe pericarp damage was 5% and 1%. The test plot crew did not observe any seed burn due to the in-furrow applications.
"Not every year is like that, but farmers should stay on top of the issue," he says.
You can e-mail Margy Eckelkamp at email@example.com.
Test Plot Family Carries On
For Adam Schlesinger, 2013 was his first year to farm full-time after his father, Don, retired. Don is a long-time Farm Journal Test Plots partner, and Adam took up that torch for this starter test plot in Illinois. Sadly, Adam was killed in an on-farm accident on May 31 at the age of 35. At harvest, Don’s brother, Bill, came to help in the field.
Thank You to Our Test Plot Partners
Our thanks go to: AGCO, Jason Marx, Dave Webster, Conor Bergin and Lindsey Pettyjohn; Williams Farm Machinery and Dave Gloor; The Andersons, Jan Finch and Jeff Balsley; Case IH, Dan Klein, Kyle Russell and Ryan Schaefer; Central Illinois Ag and Kip Hoke; Great Plains Manufacturing, Tom Evans, Doug Jennings and John Sites; Kinze Manufacturing and Susanne Veatch; Marco N.P.K. Inc.; New Holland, Mark Hooper, Gary Wojcik and Paul Canavan; Burnips Equipment and Carl VanderKolk; Schaffert Manufacturing and Paul Schaffert; SFP; Trimble and Brian Stark; OmniStar and John Pointon; Unverferth Manufacturing and Jerry Ecklund; Wells Equipment; Versatile and Adam Reid; Yetter Manufacturing, Pat Whalen and Scott Cale; Don Schlesinger; Bob Kuntz; North Concord Farms, Dick Dobbins Jr., and Kevyn VanWert; LDK Farms and Leon Knirk; Lawrence Olson; Crop-Tech Consulting, Brad Beutke, Isaac Ferrie, Austin Durst and Justin Zeeb; and B&M Crop Consulting, Vicki Williams, Megan Tomlin and Amanda Anderson.