View From the Cab

Farmers Test Crop Nutrition Needs and Weigh Weather Scenarios

Pamela Smith
By  Pamela Smith , Crops Technology Editor
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Tissue testing is an important part of managing the corn crop on Arnusch Farms, in Keenesburg, Colorado. (Photo courtesy of Marc Arnusch Farms)

DECATUR, Ill. (DTN) -- Input prices may be high enough to make one weep, but Marc Arnusch would rather grab a tissue.

With approximately 350 growing degree units accumulated in the corn crop this week, the Keenesburg, Colorado, farmer and his farm crew started sacrificing a few corn plants to use as diagnostic indicators.

Likewise, Luke Garrabrant put a call into his seedsman to kick into gear a crop nutrient analysis project. It's the first year the Johnstown, Ohio, young farmer will be using a tissue testing program to verify and fine-tune the menu for baby crops that are well on their way to having the appetites of teenagers.

Garrabrant and Arnusch report in each week as part of DTN's View From the Cab feature. The diary-like reports focus on crop conditions and other rural life topics. This is the seventh report of a season that has so far been filled with weather challenges for both farmers.

This week they talk about some of the diagnostic tools they use and how important it is to build relationships with input suppliers and how Mother Nature has the final say on most days.


Some year down the road, Garrabrant figures he'll be able to look back and remember 2022 as one giant learning curve. At age 25, he has already been farming for a dozen years at some level. But none of those crop years have stacked up quite like the current one and it has demonstrated the challenges of growing an operation.

"Last year (2021), I had all the manure spread for customers and all the herbicide burndowns done before May 1. This year, weather didn't allow me to start any operations until May 1," he said.

"When that happens, it just sets everything back. Last year, all my crops were planted by May 25. This year, I was barely started by then," he added.

Adding hired labor this year has been a lifesaver, but rains seem to come just as the fields get fit again. With 67% of his corn crop in the ground, Garrabrant pulled the plug this week on planting more corn. He'll either plant those acres to soybeans or take prevented planting on the remaining corn acres.

"Last week I had about two-thirds of my soybeans planted and my unplanted beans acres possibly just increased," he noted. "It's against my nature to not plant and I'm still crunching the numbers. It will depend a lot on what the weather gives us," he said.

DTN Ag Meteorologist John Baranick wished he could be more optimistic. The pattern in the Johnstown area will remain active through the weekend with a few rounds of showers and some possible thunderstorms.

"Rainfall may be quite scattered and hit-or-miss, however. They will probably see a couple of dry days early in the week and some heat building in, but a front will move through on Thursday (June 16) that looks to pack a punch to this part of the region," Baranick said.

"It's a long way out there as a forecast, but we could see a round of severe weather out of it. Temperatures that follow will likely be right around or slightly above normal, but nothing too crazy is expected with temperatures largely in the 80s," he added.

Weather isn't the only bugaboo. Last Sunday, Garrabrant had a clear day to plant and blew a hydraulic hose on the bean planter and had an electrical problem on the corn planter. "You know what they say: Work on Sunday, fix on Monday," he joked.

Feeling frustrated, he reached out to fellow farmers on Snapchat and learned he wasn't the only stressed farmer in the field that day. "It was a rough week for a lot of people last week," he said. "It's in our nature to do everything to get that seed in the ground and be timely about it. But we also put a lot of pressure on ourselves to do it right.

"And this year, there's even more risk than ever. There are a lot more dollars on the line with both the price of commodities and the cost of inputs to put in a crop," he continued.

"I'm at an awkward point in farm growth where I'm too big not to hire more help, but not yet big enough to justify one more person. I guess that's what they call growing pains, but I'm determined to be even better prepared for this next year because dealing with uncertainty is a large part of farming," Garrabrant said.

Given that he has sometimes been forced to plant into what he considers less than ideal conditions this year, the crops that have emerged look great. Getting additional soybean seed to cover those abandoned corn acres won't be a problem, he said. And he had some flexibility to plant a different crop on those acres since herbicides had yet to be applied.

Working closely with his seed dealer is important to flexibility, he said. As the season grew later, he called the dealer and gave him a heads up that he'd need additional seed to pump up populations. "It was here the next day," Garrabrant said.

While he will shop around to compare prices, Garrabrant values relationship building with input suppliers. He knows his buying clout doesn't always equal that of a larger farmer and tends to stay loyal when a dealer treats him well. He also values opportunities to tap into the knowledge base of the company reps he's dealing with.

For example, the tissue testing program he's trying is also connected to his seed dealer/agronomist. "I'm going into it this first year with an open book and not sure yet what I'll find, but I'll start by looking for trends.

"I have a lot of ground that varies in fertility. Some of the ground I've been taking care of for years that I've have been able to build fertility levels on compared to those I've not farmed as long. I'm looking forward to exploring those differences," he said.

"I'm also excited to see what time periods we are lacking certain nutrients throughout the growing season and what pass we can add to address that," he said.

Manure is the backbone of his crop fertility program with the bulk of that applied in the spring. He's seen farms with single-digit phosphorus levels turn around to healthy levels of 30 to 60 parts per million (ppm) with its use.

"Manure continues to be a good value and I plan to continue to use it to build fertility. As we look forward to 2023, those rates may need adjusted, depending on what it costs per ton," he said.

"I've worked to build that savings account in the soil," he said. "We might not necessarily tap into that account if prices climb, but we might not build the account quite like we've been," Garrabrant said.


Water, or lack of it, continues to haunt Arnusch. The 1.75-inch rain recorded last week helped nudge his farm out of critical drought status, but he's already wishing for another splash.

DTN's meteorologist Baranick can offer hopes for a few showers in the area, but unfortunately, they may not offset the summer heat starting to build up.

"There could be a brief reprieve in that Keenesburg area next week around Tuesday and Wednesday (June 14-15) as a front moves through. That may bring a scattered showers, but the heat turns back on by the end of the week," Baranick said. "This is the start of the hotter and drier pattern we have been expecting for the summer. They've gotten some needed precipitation this spring, but it looks like we'll start to be less active going forward."

With irrigation water extremely tight this year and an eye on this long-range forecast, Arnusch made the decision to take prevented planting on a portion of his acres. "We know we can't perfect this crop with irrigation and it will allow us to dedicate available water to the crop already planted," he said.

Some of those prevented plant acres will go fallow to be planted back to winter wheat in September. Others may get a cover crop or a planting of sorghum-sudan grass.

Stage one tissue samples were being drawn this week in corn. Mid-stage samples on wheat and barley will also be sampled this week to get a look at nutrient uptake and to determine the maturity or stage of those crops.

"In tandem with those corn tissue samples, we also take soil samples. We know what we had in the ground prior to planting. We know what we applied pre-plant or at planting. Now, in season, the question is how much of that is left in the plant and how much is left in the ground," he said.

They also overlay growing degree units (GDU) on top of information to try to understand the correlation between heat unit accumulation and plant nutrition. "We're essentially building our own farm database to see if we can find trends and cause and effect relationship to inputs applied," he said.

For example, one thing tissue tests have routinely showed is a dip in boron ppm in corn. Yet, testing two weeks later finds the boron levels adequate or sometimes above where they should be without any inputs added.

"Why do we always get that dip of boron? Is it because the plant is using a lot of it at that time? Is it something we can manipulate? Those are questions we haven't been able to answer, but we keep testing so we can learn," he explained.

"We've learned a lot on the fermentation side of things for the craft grains part of our business. We know we can change gluten strands. We know we can change protein and starch content. And that all started by taking these kinds of samples in the field," Arnusch added.

The cost of fertilizer -- particularly phosphorus and potassium -- is another important reason for testing. "They are incredibly expensive and adding a lot of cost to what we do.

"But this is also a great year to understand drought. Are there things we can do through management that can drought-proof or at least give us a leg up on drought-proofing our crop," Arnusch asked.

"We're starting to learn a lot about potassium becoming a poor man's drought guard. We know, for example, that adding just a bit more potassium (in a 2x2x2 or 2x2x3 band) close to the corn seed at panting can make the plant slightly more drought hardy," he said.

Sampling helps keep the farmer nimble on nitrogen too. He's used split applied nitrogen on corn for decades to hedge bets against volatile weather. "We want about 65 lb. of available nitrogen in the soil profile by V5. At that time, we make an assessment of what the crop potential looks like, what the markets look like and how much more it is going to take to move us forward," he said.

Arnusch prefers to have all nitrogen needs met in the corn crop by V8. "If we were on center pivots, we could apply to brown silk, but since we are in furrow irrigated, we have to front load to a degree," he said.

To do that, the farm has designed their own custom applicator. Steel tubes dribble liquid nitrogen about 2 inches away from the root ball as 3-inch-deep furrows are made in which to field irrigate.

"It is a system we borrowed from the onion industry," Arnusch explained. "That's how we knifed in our potassium, phosphorus and nitrogen to get it in close proximity to the crop. We did a lot of things there to improve quality as well as quantity and we've brought that over to corn and plan to try it on milo this year too."

Arnusch prefers to find value in applying the right ingredients at the right time in the right amounts over going for discount input shopping. "Our farm tends to lean toward loyalty with suppliers," he said.

Arnusch Farms grows and sells wheat and barley seed, so they have experiences on both sides of the buyer/seller relationship. Then there's the specialty crop sales to distillers. "I tend to take the same approach working with input suppliers that I think others expect of us.

"Communication and being straightforward in dealings are important to me. We demand a lot of our suppliers -- we are always asking questions and sometimes we don't accept their answers." he said.

"We are incredibly open to alternatives and want to work with suppliers that we know will go to bat for us when we need them. We like to buy things ahead, especially things like glyphosate, for example, that we really need at our disposal to handle fallow ground," he said.

That's been a bit more difficult in the current market. In fact, Arnusch lives only 40 minutes from a refinery, but has struggled to get clear diesel for over-the-road trucks of late. Red diesel for tractors and other off-road vehicles has yet to be a problem, but he has his eye on it.

Pamela Smith can be reached at

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Pamela Smith

Pamela Smith
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