Micronutrients On A Diet


By Russ Quinn
DTN Staff Reporter

OMAHA (DTN) -- Little things can mean a lot when it comes to crop production. Andy Barta believes micronutrients are one of the more cost-efficient inputs farmers can invest in these days -- even in the face of lower crop prices.

Micronutrients such as boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), zinc (Zn), nickel (Ni) and chloride (Cl) are essential for plant growth and play an important role in balanced crop nutrition. Plants may not require much of them, but a lack of any one of the ingredients can limit plant growth.

Still, low crop margins have farmers weighing even the smallest inputs. The challenge this year is to determine which ingredients can be trimmed and which are necessary to avoid an economic drop in yield. When micronutrients become a limiting factor, other production inputs such as water and fertilizer can also be wasted.

Foliar Applications Drop

Barta is the assistant general manager of Rio Creek Feed Mill, an Algoma, Wisconsin, ag supply business. He told DTN that micronutrients can be applied either as a dry surface application or go on in foliar applications at the time plants need the nutrients. About 80% of the micros his company applies in northwestern Wisconsin area are in the dry form, he said.

He estimated 60% to 80% of their customers used foliar applications of micronutrients during high commodity prices. Lower crop prices have dropped that usage to 5% to 10%, he said.

"We had a customer apply half his oats with (dry) micronutrients and the other half without it," he said. "The half with micros yielded 15 bushels (per acre) more and had 1-2 lbs. more in test weight. He now applies micronutrients to all his acres."

Dry micronutrients comes in packages containing 6 to 10 micronutrients mixed specific to corn, soybean and grasses, according to Barta. Different crops have different needs. Micronutrients generally cost about $6 to $8 an acre. The way to prove micronutrients are working is to tissue test the crop, he said.

Brittany Bolte, an agronomist with Rock County Agronomy Services in Bassett, Nebraska, said diverse soils in her region of northern Nebraska limit the use of micronutrients.

"We have so many issues with phosphorus, potassium, magnesium and pH in our soils here, micronutrients like zinc, boron, etc. wouldn't probably work," Bolte said.

Bolte said she knows when corn was $6 to $7 there was big push for foliar applications of micros, but she is not sure there is a consensus within the industry from both growers and agronomists if foliar micros pay. This might explain why foliar applications of micronutrients have dropped with lower commodity prices, she said.

"My guess is it still comes back to the basic need to be addressed before going with 'fancy' micros," she said. "At least that is my position and what I push with my growers - get the foundation fixed on the house before we put pretty windows and gutters on."

Apply or Not to Apply?

Wayne Martin, who farms near Shelby, Iowa, decided to stop applying micronutrients after using them in recent years. Simple math of dividing total cost by $7 corn, and now $3.50 corn, showed he was not sure it would pay back even though it makes agronomic sense to him.

"It's like walking into a casino with $1,000 or $10, you can't play if you don't have as much," Martin said. "I'm guessing my yields may take a small hit but now we need to look at top economic yield, this is what will pull us through this slump."

Martin also believes a La Nina could be in effect this summer and his western Iowa farm could see dry growing conditions as a result. He would hate to throw extra money at a crop, he said.

Trying to produce "gravy" bushels this year will be hard to do with these grain prices. Extra bushels at $7 corn adds up much quicker compared to $3.50 corn, he said.

Not all farmers have decided to pull the pull completely though. Austin Henderson, who farms near Sharpsville, Indiana, said he uses quite a bit of ammonium sulfate (AMS) as a source of sulfur as well as some nitrogen. He said he plans on sticking with AMS because he feels like it is beneficial to him as his soils are deficient in sulfur.

"Sulfur consistently shows up as deficient here, therefore we spread AMS," Henderson said. "It also releases nitrogen a little slower so I feel it helps spread out our nitrogen program."

Henderson said they test their central Indiana soils for micronutrient levels. For the most part, most his soils are at adequate levels when it comes to micronutrients.

A practice he would be willing to incorporate into his operation someday would be using thiosulfate, which would be mixed in with nitrogen during side dress applications. He is willing to try new things if there is a chance of added profit, he said.

Read more on micronutrients: http://bit.ly/… and http://bit.ly/…

Russ Quinn can be reached at russ.quinn@dtn.com

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