It’s not just green stuff in a field – forages are important when livestock are grazing them and when farmers harvest them. They’re important, and that’s why ongoing research is taking place around the country.

At the recent American Forage & Grasslands Council annual meeting, experts in that area presented a number of updates on baleage – and why it’s so important.

Dennis Hancock, Ph.D., dairy forage research center director at the USDA Agricultural Research Service in Madison, WI, kicked things off with a general baleage update. He noted farmers are following best practices. “We’re not just baling up wet hay and hoping for the best,” he said.

As a bit of history, Hancock explained that early farmers started ensiling grasses around 1500 BCE. With the right moisture, the forages will provide high nutritive value and a high concentration of water-soluble carbs.

“Why choose baleage over hay?” he asked. The answers: there’s a reduced risk of rain and storage losses; it enables timely harvest; there’s less shatter loss; the forages retain leaf better; and it increases digestibility and palatability for livestock.

Following up was Matt Akins, research leader with USDA-ARS’s Environmentally Integrated Dairy Management Research in Marshfield, WI. He presented “Recent Research & Techniques for Improved Baled Silage Production,” which included a lot of work he did with Wayne Coblentz, a now-retired ARS research dairy scientist.

Akins first addressed the topic of baled vs. chopped forages, noting that fermentation is much slower in baled grasses. Chopped forages release sugars faster and have increased moisture. The pH also drops faster with chopped.

When it comes to moisture management, 45% to 55% moisture recommended. “Why not bale wetter?” Akins posed. The reasons make sense. There’s farmer safety (as undersized tractors can’t handle heavier loads), proper equipment use (as most balers handle drier material better) and wetter forages increase the risk of clostridial fermentation, which may cause anaerobic deterioration of silage, either through undesirable rancid odor or through the accumulation of ammonia and amines in Clostridium species. That can lead to risks to animal health and milk contamination.

When it comes to dry silage, “an implication for management is that fermentation (or decreasing pH) is relatively unimportant in producing high quality dry (greater than 55% dry matter) silages,” according to a 1988 study from R.E. Muck. Akins added that an observational trend is that producers are moving toward dried baled silages, placing more emphasis on excluding air with plastic wrap and less emphasis on fermentation.

The key is sealing everything properly. Farmers should wrap the forages as quickly as possible after baling. Hancock said within four hours is ideal, but Akins noted that producers only see minor damage within the first 24 hours.

When wrapping, use six to eight layers of stretched plastic (of 1 mm or 25 microns) for long-term storage. After wrapping, storage site selection/maintenance is also important – pallets and concrete pads are best, and always keep them away from hedgerows. Isolate everything from cattle, pets and vermin as best you can. Do your best to not puncture the plastic. If necessary, patch holes with the appropriate tape.

When it comes to aerobic stability, Akins said the use of propionic acid-based preservatives works well in alfalfa/grass silages. They help keep temperatures down when the wrapped forages are opened, plus there’s an extended useful feeding window if they’re used properly.

In cold weather, freezing temperatures will severely slow fermentation, but it will start again when things start to thaw. “But you may see yeast issues, due to high sugar content not used in the first fermentation,” Akins warned.

To see the best results, Akins said producers should also diligently address other management details:

  • Maximize bale density (aiming for greater than 10 lbs. of dry matter per cubed foot)
  • Consider an inoculant, especially is forage is damaged, manure has been applied or if the bale moisture approaches 60% (especially if it’s heavy on alfalfa) – grasses are a bit more forgiving
  • Apply plastic wrap promptly and properly
  • Remember that the use of an acid preservative may help improve the aerobic stability of ideal moisture baled silage but it had limited effects on dry baled silage

In conclusion, Akins said, “General observations suggest that forages are baled at increasingly lower moisture concentrations, placing additional emphasis on exclusion of air.” Protect the product to protect the animals that consume it.

by Courtney Llewellyn