Silage bunker

Much of the safety risk around bunkers involves machinery accidents while filling and avalanches when removing feed. Iowa State Extension specialist Hugo Ramirez says producers should remove silage from the top of the pile first.

A late start to planting translated into a late start to the silage harvest. Better weather over the last couple of weeks, however, has choppers rolling.

“It seems to be coming along,” says Hugo Ramirez, Extension dairy specialist with Iowa State University. “We’ve had enough growing degree units that the corn has been pushed far enough along that frost is not a major concern.”

He says the university’s recent silage harvest resulted in about 7.5 to 8.5 tons of dry matter per acre. Ramirez says these yields are pretty normal for the ISU harvest. He did say the corn was a bit more mature than in past years, providing more starch compared to a year ago.

Farmers in southeast Iowa started chopping silage about three weeks ago, Ramirez says, with the rest of the state following along. He says if silage is chopped after a frost, an inoculant could be used to help it ferment correctly.

“A frost could affect the naturally occurring bacteria that aid in fermentation,” he says.

Patrick Wall, Iowa State University Extension beef specialist in Knoxville, Iowa, says with custom choppers few and far between, the silage harvest is running a bit more slowly than usual. He says issues with lodged corn are also slowing down progress.

“We have some pretty major wind damage in some of these fields,” Wall says. “Yields have been all over the place.”

Most of the dairies in Erika Lundy’s area are pretty much done with silage chopping, the Iowa State Extension beef specialist in Greenfield says. Feedlots and cow-calf operators are still working on it, she adds.

With high corn and hay prices over the past two or three years, Lundy says more producers are interested in silage.

“We get a lot of calls,” she says. “We’ve seen more interest from beef cow producers than we have in years past.”

Lundy says moisture levels need to be correct before bagging or storing in a bunker.

Ramirez says silage needs to be at 35% dry matter, or 65% moisture, and make sure it is packed tightly in the bag and ensure proper fermentation.

He says if using a kernel processor, the particle size needs to be about three-quarters of an inch to allow bacteria access to sugar and starch in the plant. If a kernel processor is not used, the particles should be a quarter- to half-inch in length.

Ramirez says opening up the kernel results in better feed quality and energy utilization.

He says the ideal density for bunker storage is 40 to 45 pounds of fresh forage or 14 to 16 lbs. of dry matter per cubic foot.

Plastic covers should be at least 4-millimeters thick, Ramirez says. The covers should be able to resist tearing and block ultraviolet light. Weight is needed on top of the cover, with old tires being among the more popular options.

Ramirez also stresses the importance of safety around harvest and storage. He says silo gas can be particularly dangerous, especially in upright silos. He suggests producer stay away from the silo for at least three weeks, then run the blower for 15 to 20 minutes with the door near the top of the silo open before entering the structure.

Much of the safety risk around bunkers involves machinery accidents while filling and avalanches when removing feed. Ramirez says producers should remove silage from the top of the pile first.

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Jeff DeYoung is livestock editor for Iowa Farmer Today, Missouri Farmer Today and Illinois Farmer Today.