Also called “baleage”, there are two types of baled silage: individual wrapped bales and continuous wrapped bales. The individual wrapping system — for round and square bales of different sizes — consists of applying several layers of a stretched plastic film around the bale. Once the bale is fully covered by plastic, anaerobic fermentation can start. The continuous wrapping system uses the same plastic-stretching technique, but the bales are placed side-by-side, creating a tube of bales.
When choosing to create silage in either individual or continuous wrapped bales, be sure to keep in mind the following advantages and disadvantages:
- Flexibility to harvest regarding stage of maturity
- Easier to harvest small volumes
- Allows segregation of different cuts
- Offers option when weather doesn’t allow harvesting dry hay
- Easier to transport and more suitable for selling forage
- Requires specific equipment
- Higher cost per ton of forage ensiled
Filling and Packing
Site preparation is critical for baled silage. Place bales on a non-abrasive floor to help prevent damage to the plastic covering, preferably on the flat side of the bale where there are more layers of plastic.
The ideal moisture content for baleage is between 40% and 55%. This will create a condition for proper fermentation and longer-term storage when the bales are wrapped. Dry matter losses will be lower when harvesting at these moisture levels. Bales can be efficiently made at a lower DM but should then not be stacked due to plastic slippage that leads to air entry and associated feed-value losses and spoilage growth.
Make bales the size and weight for the wrapper and loader. If crop moisture is high, bales can be quite heavy. Be sure the loader can handle the extra weight. Heavier bales also have more problems with plastic tears and holes while wrapping, stacking and in storage.
For optimum preservation, bales should be wrapped within 24 hours. Delaying wrapping can escalate the risk of silage heating, lower forage quality and raise spoilage losses.
Covering and Sealing
Apply at least six layers of plastic around the bales. An extra layer can be applied for more fibrous forages, like alfalfa, where the risk of tearing from tough stems is higher.
Maintenance of the baler to remove tack from the rollers is crucial for efficient plastic application and build up should be removed daily.
The overlapping in between two layers needs to be 50%, meaning that from one round to another, the progression is half the width of the plastic layer. The stretching needs to equal 50%, meaning that an initial length of 19 inches, or 50 cm., will become 29 inches, or 75 cm., after stretching the plastic around the bale. This gives the ideal impermeability.
Control plastic integrity during storage to reduce spoilage losses.
With the high investment in wrapping bales, it is essential to control feeding losses.
Producers can use a ring feeder, mobile feed carts or tub grinders (depending on the bale size) to help limit losses during feedout.
The feed quality of large round bale silage, especially those bales with a high proportion of legumes, may cause overfeeding to some animals. Consider strategic feeding of baleage and/or restrict the amount of bales available at any time.
The typical life of silage stored in bags is around 12 months due to plastic integrity issues.
Check out these resources written by silage experts for more information on creating high-quality baled silage.
- Large Round Bale Silage (Penn State Extension)
- Making Quality Silage Bales (UW Extension)