Treating corn stover with lime (calcium hydroxide) and water can produce a palatable, economical feed for beef cattle, dairy heifers and dry cows, speakers told about 125 farmers in late October who attended a field day sponsored by Landmark Service Cooperative at the Dean and Drew Manthe Farm near DeForest.
Steve Petersen, end use product manager with Monsanto's Corn Product Management team in Iowa, said that today's high-yielding corn plants produce more crop residue than corn produced 10 or 20 years ago.
Corn fields yielding 200 bushel per acre or more create enough residue that it "becomes both a challenge and an opportunity," Petersen said.
"When corn is harvested, 58% of the dry biomass is grain, leaving 42% that is made up of corn cobs, stalks, husks and leaves," he explained.
Petersen estimated that there is 100 million tons of corn stover that could be harvested just in the Midwest.
"We're going to double corn yields by 2030. We can't handle the corn stover we have now," he noted. "What are we going to do with it?"
Petersen said farmers are already having difficulty no-till planting corn into corn residue.
Because many producers are growing Bt corn, the stalks have more lignin and don't break down during winter like older hybrids.
Growers are reporting that they are making more trips in the field to get rid of the residue, especially in corn-on-corn.
~~~PAGE_BREAK_HERE~~~"We asked growers in the central Corn Belt and 80% tell us this is a real problem," Petersen said. "The question remains is the amount of stover enough to create a business opportunity. Properly done, harvesting corn stover can increase the value of an acre of corn. Improperly done, harvesting will damage the fields."
Monsanto has been partnering with Archer Daniels Midland, and several universities including University of Nebraska, Iowa State University and University of Illinois and most recently University of Wisconsin-Madison to study if calcium hydroxide enhances digestibility and nutritional value of stover allowing for the replacement of a substantial portion of grain in cattle diets. In the UW-Madison study, corn stover is being fed to lactating dairy cows at the U.S. Dairy Forage Research Farm near Prairie du Sac. The study, which began last February, is expected to be completed by spring 2013.
According to university studies at Nebraska, Iowa State and Illinois, up to 25% of corn feed was replaced with lime treated corn stover with no adverse impact on cattle's physical development. The lime treatment works by raising the pH level resulting in decreased fiber (lignin) making corn stover more digestible and nutritious.
A Nebraska trial involving 336 steers over 140 days concluded that feed comprised of 20% treated corn stover performed as well as the typical untreated high-grain diet. In a similar six-month trial at Iowa State involving 210 steers, lime treated corn stover fed with dry distillers grains enabled the percentage of grain in animals' rations to be cut between 35% and 70% without affecting their development.
Old idea that's new again
Calcium hydroxide can be applied on windrows of corn stover in the field prior to chopping or baling.
Petersen said, applying lime, or calcium hydroxide, to corn stover isn't rocket science.
~~~PAGE_BREAK_HERE~~~"This is an old idea that's new again," he said. "We did this in the early '70s. Why? Because we had $3 corn. Why was it discontinued? Because corn prices dropped to $1.50 a bushel and nobody cared anymore about feeding less corn. High corn prices are bringing it back."
Jim Straeter, a New Holland machinery dealer from Rochester, Ind., spoke about the corn head attachment he designed to shell the corn while also placing the stover in a windrow so it can be harvested easily.
The windrow can be harvested with a chopper or a large baler depending on the intended use and on the moisture level in the stover.
Straeter showed a video of his corn head moving through the field at 3 mph and another video of the head harvesting corn with snow on the ground. Straeter said that even in very challenging conditions there were no clumps in the windrow. Moisture, however, is a challenge when it comes to this new technology.
"You can't control the weather you just have to work with it," he explained. "You want to harvest the grain when it's right to harvest the grain because that's the main crop, but once you shell the corn you have to deal with that windrow."
Straeter said that in trials he conducted under various weather conditions, a merger worked very well to help dry the stover windrow for baling.
He designed and patented his Cornrower attachment to go on a New Holland 99C chopping corn head. The system catches the stover under the corn head and creates a uniform windrow. After the corn is shelled, the combine deposits chopped husks and cobs on top of the windrow of stalks and leaves.
Straeter said the goal is to decrease the dry down time for the stover and decrease extra trips through the field.
"If you're going to bale the stover, the windrow has to dry," he explained. "If you're going to chop it, it can be deeper. It's really important to get the windrow even if you're going to dry it down and bale it."
Field tests Straeter has done show that stover windrows created by his attachment result in improved baler intake, bale density and bale shape compared to windrows created by conventional methods of doing the same job. The material windrowed by his invention produces a material that feeds uniformly and packs easily.
Straeter said that his process reduces the amount of dirt and the number of rocks in the stover and chops it in a way that the material will be much more user friendly in a TMR mixer.
~~~PAGE_BREAK_HERE~~~According to Straeter, the Cornrower attachment doesn't affect combine performance or grain quality or grain loss.
He said, "If you're going to harvest stover, it has to be sustainable."
This year in his area, farmers were able to make up to $100 per acre from the harvest of their corn stover for bedding. Because feed is in such short supply due to the drought, farmers harvesting treated corn stover for feed were getting around $400 per acre.
Straeter said the new Cornrower will be offered by New Holland in August 2013 and will be available in 8-row, 30-inch and 12-row, 30inch widths "and we can adapt it over to 38-inch rows."
Checking out the latest technology
Father and son Dean and Drew Manthe hosted the Corn Stover Field Day sponsored by Landmark Service Cooperative at their farm near DeForest in late October. The Manthes farm 2,000 owned and rented acres in partnership and custom raise 1,500 dairy heifers.
This is the first time they have put up treated corn stover and fed it to dairy heifers, Dean said.
"I heard about it through UW-Madison Farm and Industry Short Course," Drew said. "It's an economical feed. We thought we'd cut back on feed costs and give it a try."
The Manthes had Jim Straeter demonstrate his new Cornrower and put up 50 acres of treated corn stover.
Next year, Drew said he and his dad are planning to harvest 300 acres of treated corn stover.
"We have a stalk chopping head on our John Deere corn head," Drew explained. "Next year, we'll just rake a windrow behind the combine, treat the stover and chop it and store it in a bunker."