Forage quality doesn’t increase after harvest, so what methods will ensure haylage yields are of optimum use to animals?

Experts have spent years researching what steps affect forage nutrition, and even minute details can alter the makeup of forage.

“Remember, hay is the highest quality the day it’s cut,” says Dan Undersander, forage agronomist at the University of Wisconsin – Madison. “We want to preserve that quality through the harvesting process.

The higher the quality, the more animal performance we’ll get in terms of weight gain or milk production.”

Undersander says the cutting height should be the first step in your forage management system – and I couldn’t agree more.


Cutting height is vital and, in terms of quality, getting that cutter bar off the ground 3 or 4 inches – whatever it may be depending on the grass – is paramount. When selecting a mower conditioner, ask these questions: How high can it cut? How high can I get the cutter bar off the ground?

Is there a way to get it off the ground without tilting the head back? Tilting the head forward may result in a cleaner cut.

Undersander recommends cutting legume crops at 3 inches, cool-season grass at 4 inches and land grass or millet up to 6 inches.

“The grass stores energy in the base of the stem, and if we cut too short, it won’t regrow as fast and won’t yield as much for the year,” Undersander explains. “Alfalfa, on the other hand, and clover store energy in the root, and you can cut them shorter because they will regrow from those carbohydrates in the roots.”

Undersander recommends a 3-inch cutting height for alfalfa. While cutting lower results in more tonnage, it’s all stem and low-quality forage. Secondly, the lower the cut, the more soil that can be picked up (particularly with disc mowers) when the soil is dry.

“We have seen samples that run as much as 15 to 18 percent ash,” Undersander says. “Inside the grass or alfalfa, we have something close to around 6 percent ash. So that means these people have picked up 10 percent dirt. Beef cattle don’t gain weight eating dirt, and cows don’t milk eating dirt.”

Undersander says keeping ash content below 10 percent – allotting an estimated 6 to 8 percent inside the plant and 1 or 2 percent dirt – is a doable goal that’s essential to nutrition.

“Each percent of ash reduces the TDN [total digestible nutrients] content by 1 percent because it’s 1 percent less nutrients and 1 percent less minerals,” Undersander says.

Undersander says levels of starch and sugar in the forage are 100 percent digestible at harvest. No matter what type of forage you’re growing, the first 15 percent of moisture should be dried off quickly in order to keep these levels high for the animals.

The faster the drydown, the faster you shut down the respiration, and the more starches and sugars can be preserved.

“To dry hay as quickly as possible, first properly condition the hay and make a wide swath,” Undersander says. “When conditioning the hay, you can use either a flail conditioner for grassy crops or a roller conditioner for legume crops.

Using a roller conditioner for legumes means less leaf loss. We want to maintain that quality of the leaves and keep it in the final product.”

With either type of conditioner, it’s important to properly adjust the head to ensure adequate conditioning occurs and adjust into a wide swath covering 70 to 80 percent of the cut area. Going to a wide swath conditioner makes sense because you expose more of the crop to the sun.

Baleage is an alternative that can provide quality hay with less drydown time.

“We need three to five days of drying to get quality hay, but with baleage we can get put it up in one or two days and have even higher-quality forage because we’ll have reduced leaf loss,” Undersander says.

“So baleage can be advantageous by letting us harvest in a time when quality is high but maybe rain is on the horizon. You still end up with higher-quality forage for the animals.”  end mark

PHOTO: Cutting season. Courtesy photo.

Josh Vrieze is the product manager with Vermeer Corporation. Email Josh Vrieze.


156166.pngCutting height

Legumes – 3 inches

Cool-season grasses – 4 inches
Land grass or millet – 6 inches

Ash content
Keep total ash content at 10 percent or below which allows for:

  • 6 to 8 percent of ash inside the plant
  • 1 to 2 percent dirt

More tips and tricks

  • 15 percent of moisture should be dried off as quickly as possible to preserve starches and sugars.

  • Adjust for a wide swath (covering 70 to 80 percent of the cut area) when mowing for a faster drydown.

  • Use a flail mower/conditioner for grassy crops.

  • Use a roller mower/conditioner for legumes.

  • Adjust mower head to tilt forward (not backward) for the cleanest cut.

Questions to ask your hay equipment dealer 

When purchasing a mower conditioner, ask:

  • How high can it cut?

  • How high does the cutter bar come off the ground?

  • Is there a way to get the cutter bar off the ground without tilting the head back?