Jessica Williamson, Penn State Extension
Wrapping wet bales for baleage could help to ensure your hay fields are harvested at the correct stage of maturity, providing adequate quality for livestock.
First and foremost, good quality baleage must be achieved by baling at the proper moisture content. Rather than aiming for 16-20% moisture, which is the common target for dry hay, forage can be baled for baleage at 45-65% moisture. The proper moisture content allows for optimal fermentation after the bale is covered and sealed and oxygen can no longer penetrate the bale.
When individually wrapping bales, plastic should be about one mil (25 microns) thick low-density polyethylene and each bale should be wrapped a minimum of 6 times, but 8 is more ideal, with at least a 50% overlap. As the bale is wrapped, the plastic is stretched thinner than the original material, causing the need for multiple layers to ensure elimination of oxygen, sunlight, and excess moisture. If the bales being wrapped have sharp stems, more layers of plastic can be useful in preventing holes from being poked through the wrap, allowing air to infiltrate the bale. More mature, lower quality forage or drier hay should also have more layers.
Wrapping within 4 hours of baling helps to ensure proper fermentation and reduce the exposure of the bale to air. The longer a bale sits unwrapped after baling, the higher the potential internal temperature of the bale can rise, causing an increased incidence for heat damaged proteins and reducing the overall quality of the forage. Internal bale temperature should remain below 120⁰F to eliminate the risk of heat damaged protein occurrence. To reduce this risk, research has shown that bales should be wrapped within 12 hours after baling, but the sooner the better.
Wrapping close the area where the bales will be stored helps to lessen the probability of plastic getting torn during transportation. Storing the wrapped bales in a well-drained area where water will not accumulate on the ground is essential.
Paying attention to smaller details can help to increase the quality of your wrapped forage. The addition of bacterial inoculants can help to ensure proper and consistent fermentation throughout the entire bale if moisture level is not ideal. It is also important to asses each bale after wrapping to ensure there are no holes punctured through the plastic. If so, use tape specially designed for repairing holes in bale film.
Baleage can provide a unique opportunity to harvest optimal quality forage during weather that is not usually ideal for dry hay. Take advantage of the opportunity to wrap bales during less-than-ideal weather patterns to ensure adequate feed for your livestock during the winter.