Cornstalk Economics

By Loretta Sorensen
DTN/Progressive Farmer Contributing Editor

Over the past 15 years, Travis Krein has leased cornstalks to help feed his herd. Taking 1,000 head of his 1,300-head Black Angus commercial cows to harvested Nebraska corn fields has helped relieve grazing pressure on his pastures at his Broken Arrow Angus Ranch, in Harrison.

Krein has always operated with a simple verbal agreement when it comes to his cornstalk lease. As the practice has grown, there are now many different types of agreements and as many details in those agreements as there are farmers and ranchers.

"We've been leasing cornstalks from the same landowners for 15 years," Krein said. "They furnish fence and water, and take care of daily chores, checking cattle two or three times per day. We bring the cattle in and cover the cost of minerals, salt and any necessary supplement during adverse weather. Every seven to 10 days, one of our hands makes the rounds to lay eyes on the cattle to see that they're healthy and maintaining body condition scores. Otherwise, we don't see them 'til they come back home in late March or the first of April."

When Krein established his ranch around 2000, he didn't have enough pasture to winter cattle. While that's not the case anymore, he said grazing cornstalks is an important economic option for winter feed.

"Leasing cornstalks has been cheaper than purchasing hay," Krein said. "It also means we have more forage in our pastures and can bring in more cattle over summer."

WHERE CORN GRAZING FITS

University of Nebraska Extension beef specialist Rick Rasby believes more Nebraska corn growers could find a market to lease their cornstalks if ranchers calculated feed cost savings, and crop producers penciled out added potential income on the exchange.

"Grazing cornstalks is something we encourage beef producers to look at very closely to see how it might fit their operation," Rasby said. "Some corn growers have concerns about soil compaction, but in the data we've gathered, we've never found evidence of significant compaction."

Rasby's research shows cows do best on cornstalks if they go into winter with a body condition score (BCS) of 5 or above. The nutrient profile of corn husks and leaves is between 5 and 5.5% crude protein (CP), and 55% to 56% total digestible nutrients (TDN). In contrast, bromegrass averages 9.2% CP and 55% TDN; prairie hay, 5.8% CP and 50% TDN; and Timothy grass, 6.8% CP and 57% TDN.

Rasby notes water and fencing issues, as well as an imbalance of supply and demand in some areas of Nebraska, are part of the reason only about 25% of the state's harvested corn acres are leased for grazing.

"There are fewer cows in eastern Nebraska, too," Rasby added. "Across the nation, fewer crop farmers raise livestock, so some corn growers have less experience managing cattle, which means they may not be comfortable with the responsibility of taking care of cattle on cornstalks. A lease agreement has to be something that benefits both sides."

In the first days of grazing stalks, cattle select the nutritionally highest feedstuffs in the field. They typically start with downed corn ears, then move to corn husks, leaves and finally cobs. Krein's landowners manage that behavior by rotating cattle through sections of a corn field. They may move them through as many as eight times during the grazing period.

"We know our cattle's body score condition maintenance and weight gain are best early in the winter," Krein said. "As the season progresses, we especially watch older cows and heifers to ensure they're getting adequate nutrition while they graze stalks. Statistics vary from field to field, but our baseline stocking figure is half an acre per cow per month."

STRIP-TILL LEASER SEES POSITIVES

Jon Holzfaster, Paxton, Neb., has leased out corn acres for grazing since his family started growing corn in the 1970s. He provides fencing, water and daily care, and places out minerals, salt and any protein supplements ranchers supply.

"Every rancher and farmer has a different approach to leasing stalks," Holzfaster said. "The key to a successful arrangement lies with the relationship between the farmer and rancher. Most of our ranchers have been bringing cattle here for many years. We know what they expect, and they know what we provide."

Holzfaster, who utilizes strip-till across his cropland, added he hasn't experienced any compaction issues because of his lease. He finds removing a portion of the corn residue actually helps reduce potential planting issues that might result from wet or heavy residue, and hinder seed placement.

During the years, Holzfaster's seen financial arrangements between ranchers and landowners range from 0.5 cents per head per day to as much as $1.25 per head per day.

ECONOMIC AND VARIETAL SHIFTS

Krein, who found grazing stalks a highly positive economic option 15 years ago, said changing agricultural conditions and rising lease costs are limiting the economic benefits of this option.

"With the 2012 drought, cornstalks were in high demand in 2012 and 2013," Krein said. "The rising costs nearly made grazing stalks cost prohibitive when you considered the freight expense of moving cattle. Those lease values haven't gone down the past couple of years, making feeding hay at home over winter a more attractive option."

Krein said he's observed that some newer corn hybrids appear to be less nutritious or palatable to cattle. That increases concerns about maintaining body condition and providing adequate feed to pregnant cows.

"I'm not certain if it's corn variety or what, but we've seen cattle graze one corn field aggressively and graze one right across the road much less," Krein said. "We also watch our heifers and older cows more closely these days, as they seem to have more difficulty obtaining adequate nutrition than they did in past years."

Krein added that modern harvest equipment does such a thorough job of capturing corn ears, cattle today find significantly less downed corn in today's fields -- despite the higher cost of grazing.

"Gross margins in beef production are so tight now, we'll have to see if grazing cornstalks remains a viable economic benefit," he said.

THE PROTEIN QUESTION

University of Nebraska researchers conducted a five-year study (2004--2009) looking at the effects of providing a protein supplement to beef cows grazing cornstalks in late gestation. The study considered both cow and calf weight, as well as reproductive performance.

Supplementation resulted in improved cow body condition scores (BCS) at the end of cornstalk grazing. Calf weight, cow pregnancy rates and reproductive traits of subsequent heifer progeny were not impacted by the supplementation program. And supplementing mid- to late-gestation beef cows grazing cornstalks had minimal impact on cow performance or fetal programming of heifer progeny.

The supplement used in the study was a protein/energy range cube comprised of two-thirds dried distillers grains (DDGs). Each year of the study, cattle numbers ranged from 158 to 172 head. Changes in body weight (BW) and BCS were recorded three times during the year in October, February and May.

Corn ear drop was estimated in each field prior to grazing (two 178-acre irrigated corn fields). Ear drop was similar for each field each year, averaging 1 bushel per acre.

Researchers developed an equation to determine grazing days and the amount of supplement fed. Cows receiving supplement were started on it 20 days after grazing began. They were fed 2.2 pounds per head of supplement per day. Conclusions from the study included the following:

-- Supplementing cows grazing cornstalks in mid- to late gestation did not improve cow reproduction or calf performance.

-- Supplementation did not affect growth or reproduction of heifer progeny.

-- Protein supplementation was not found necessary for cows grazing cornstalks, given they started the grazing period in adequate body condition (BCS of 5).

(VM/CZ)

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