Maximizing Corn Yield
CropLife Media Group's Webinar focuses on an often overlooked but essential nutrient: zinc.
March 14, 2011
Given today's high-yielding corn genetics, favorable crop prices and volatile input costs, getting the most out of every acre is more important than ever. But how do you do this efficiently and affordably? And what can we learn from the production practices of past corn yield challenge winners?
That was the subject of CropLife Media Group's recent webinar, "Innovative Fertilizer Strategies for Maximizing Corn Yield," presented by Wolf Trax Director of Research and Development Mark Goodwin.
Instead of starting with the traditional areas of NPK and crop protection products, Goodwin assumed that most growers have this area well under control. Instead, he focused on the small and relatively inexpensive "tweaks" that high-performance growers can focus on to get the yield jumps. These tweaks include an often overlooked but essential nutrient: zinc.
Most growers are familiar with the concept of the "Law of the Minimum," which states that the most limiting nutrient limits yield, regardless of how much of other nutrients you apply.
"Building yield potential is similar to building a barrel," said Goodwin. "Each stave in the barrel represents an individual nutrient. No matter how tall the other staves are, the shortest stave determines how full the barrel can be. Zinc can sometimes be the lowest stave — or the limiting nutrient for maximum yield potential. No matter how much NPK you apply, if zinc is short, yield will only reach the amount zinc allows."
He also noted that the barrel is changing in today's corn production. "With recent advances in yield potential due to genetic and technological traits, the barrel has become bigger and taller," he noted. That means bigger yields — but also an increase in overall costs (and risk) to make sure the correct nutrient balance is in place.
Get Your Zinc In Sync
Goodwin shared information from Ohio State University that showed the zinc to P ratio is especially important in maximizing yield; a ratio of 100 or 150 to 1 should be maintained. Data from the University of Minnesota showed that where soil zinc levels are low, increasing P did not result in higher yields unless zinc was applied as well.
Goodwin recommended growers using Variable-Rate Technology should increase or decrease their zinc level in tandem with their phosphorus. Wolf Trax DDP Fertilizer coating technology enables growers to meet this nutrient need efficiently and easily. Because each and every prill of fertilizer is coated with Wolf Trax Zinc DDP, the nutrient balance is easy to maintain. As P application increases, the zinc coating ensures zinc levels increase as well.
The second reasonably priced step Goodwin recommended for corn growers is to pay extra attention to their crop's zinc needs. Several indicators can help growers check for zinc deficiency, including soil tests, tissue tests and visual deficiency symptoms of past crops. "Paying attention to zinc levels is especially important in high P soils," he said.
What Are High Yield Growers Doing?
Lastly, Goodwin noted that traditional approaches to micronutrient application may no longer work when growers are aiming for "shoot for the moon" yields. He referenced recent corn yield challenge winners, noting their yields are consistently 100 bushels per acre higher than the national average. One production practice the majority of these growers employ is to seed early and use a fertilizer strategy designed to help the plant cope with unfriendly cool and wet soils. For these growers, use of a micronutrient package along with starter fertilizer was the key.
"Micronutrients — especially zinc — and starter fertilizer is a foundation for seeding early into cold soils," said Goodwin.
Wolf Trax has two products that help growers achieve early zinc uptake, including Zinc DDP as a fertilizer coating, and PROTINUS, a seed-applied fertilizer. "Zinc DDP, coated on fertilizer, delivers a blanket-like coverage to the field, ensuring early plant root access as soon as it hits the N, P or K fertilizer," said Goodwin. This compares to traditional granular zinc that is unevenly and sparsely distributed across the field, which may lead to a delay in uptake.
PROTINUS delivers a small amount of zinc directly to the seed, which is available as soon as it begins growing, resulting in earlier emergence, larger and more robust seedlings and a bigger root system. This all adds up to help the plant cope with early season stress. "The early plant health benefits of PROTINUS make it a great tool for growers hoping to seed early into cold, wet soils," said Goodwin.