Various words are locally used to describe the distinct types of covering that can be applied over silage clamps, bunkers or piles, and there is sometimes confusion of exactly what means what. 

Here is a rough guide to how we use a few key terms on our website:

• Silage Covers / Silage Sheets
  A broad term to reference any kind of sheet or layer of protection that goes on top of the silage clamp or forage pile.
• Silage Films
  Generally refer to the thinner “clingy” films made from polyethylene (PE) and oxygen barrier films that tightly wrap over the undulating surface of the silage to form a tight seal and prevent oxygen ingress.
• Oxgen Barriers / Barrier Films/ Silage Barriers 
  Silage barrier films, also known as oxygen barrier films, are designed to create an effective shield against oxygen penetration.  
  
  When choosing a barrier film, it is essential to select one specifically designed and manufactured with materials that effectively prevent oxygen transmission.
  The best products feature very low oxygen transmission rates, ensuring proper anaerobic fermentation. Be cautious when selecting a product—ensure it's a true oxygen barrier and not a type of plastic that allows oxygen to pass through, as this will compromise its effectiveness.
  
  Oxygen barriers for silage are relatively thin and should be gently draped over the silage pile, resting on the surface, and filling any crevices to create a barrier that blocks air pockets.
• Protective layer / Protective sheet / Protective silage cover / Silage nets / Woven covers
  Most often refers to an additional layer that is placed over the thinner film or oxygen barrier, adding a thicker and more durable layer that is more resistant to the weather, UV rays, and pests and birds. 
  
  Sometimes the protective layer is combined on the same roll as the oxygen barrier to provide an all-in-one solution that allows faster unfolding and a single application.

Silage Covers are essential for maintaining forage yield and quality, reducing spoilage and dry matter loss, and ensuring the silage provides optimal nutrition to livestock.

A good silage cover will not only keep out water, but also oxygen which is the key enemy of silage.  Oxygen impairs the fermentation process, resulting in invisible losses in dry matter, as well as the more visible wastage from decay and top spoilage.

Not all covers perform equally in preserving silage yields.  Passion Ag’s Oxygen Barrier Films work much better than covering silage bunkers with standard polyethylene (PE) films, because they are designed to keep oxygen out much more effectively.

Here’s a few more details on the benefits you can expect:

Improved Fermentation:

Anaerobic Environment: Covering silage with an oxygen barrier film guarantees an anaerobic (oxygen-free) environment, which is necessary for proper fermentation. This process produces lactic acid, which preserves the silage by lowering the pH, and stopping the growth of spoiling micro-organisms.  The better the oxygen seal, the better the preservation of your silage yield.

Preservation of Nutritional Value:

Prevent Silage Spoilage: Oxygen entry through non-oxygen barrier films can lead to aerobic fermentation, causing spoilage and a loss of valuable nutrients in the silage.

Retain Nutrients: Properly sealed silage maintains its energy; carbohydrate protein, and fibre content, which are essential for animal productivity.

Reduction of Dry Matter Loss:

Minimise Dry Matter Loss: Poorly covered silage can suffer significant dry matter loss due to oxidation of nutrients such as starch and protein, leading to the reduction of silage quality and yield.

Lower Shrinkage: Covering silage with an oxygen barrier film helps reduce shrinkage losses, ensuring more feed is available for use.

Reduction of Waste:

Reduce Undesirable Microbes: Proper anaerobic fermentation inhibits the growth of undesirable microbes like moulds and yeasts, and aerobic bacteria that can spoil the silage, making it less nutritious and digestible, unpalatable, and even dangerous when fed to the livestock.

Increase Livestock Performance:

Less spoiled silage means healthier and more productive animals. Spoiled silage should never be fed to livestock because it can contain pathogens and toxins that are responsible for reducing feed intake and impairing animal health and performance.

Economic Benefits:

Cost-Effective: By reducing spoilage and shrinkage, covering silage with a good oxygen barrier can be more cost-effective, as it maximises the amount of usable feed.

Better Feed Efficiency: High-quality silage is more digestible and can improve feed efficiency and animal performance, potentially reducing the need for supplemental feed.

Environmental Impact:

Reduce Run-off: Covered silage is less likely to generate effluent run-off, which can pollute water sources and create environmental hazards.

Lower Greenhouse Gas Emissions: Properly preserved silage emits fewer greenhouse gases compared to spoiled or improperly managed silage.

Animal Health:

Reduce Mycotoxins: Spoiled silage can contain mycotoxins, pathogenic bacteria and other harmful substances that pose health risks to livestock.

Consistent Feed Quality: Covered silage ensures a consistent and high-quality feed supply, that improves intake and contributes to better overall animal health and productivity.

Although they can look quite similar at a glance, their function and performance are hugely different. The physical difference between polyethylene (PE) film and oxygen barrier film lies primarily in the material composition and the specific layers or materials used. 

Polyethylene films and PE covers are tough and offer good moisture resistance for protection from the weather, however, they lack the oxygen barrier properties for the strict oxygen control that enables the anaerobic fermentation process that is crucial for high quality silage preservation. 

Oxygen barriers are usually more complex in their structure, often involving co-extrusion or lamination to combine multiple layers of special materials such as EVOH (Ethylene Vinyl Alcohol) or Nylon (Polyamide) that more effectively prevent oxygen from passing through.

Oxygen entry is one of the biggest causes of silage spoilage, so the less oxygen that can penetrate the silage clamp/bunker or pile, the better! 

Without this critical benefit, the use of a standard cover is less effective or efficient in preserving the valuable nutrients that are contained in the forage.

Due to their specialised materials and manufacturing process, oxygen barrier films are usually priced slightly higher than basic PE films, but depending on the specifications of some brands, the difference of converting from a premium PE cover to an oxygen barrier could be negligible or even cheaper!

Using an oxygen barrier film for silage provides superior protection against oxygen-related spoilage, resulting in higher-quality feed, reduced losses, and better overall efficiency in silage management, so although the cost might be higher than a basic PE film, the return on investment could be better for your bottom line.

The return on investment of using silage clamp covers can be optimised by using higher quality oxygen barriers and protective coverings. 

The cost of the material used to cover the pile is only part of the overall cost of silage preservation, after taking into consideration fuel and labour for compaction and physically covering the heap. 

The superior preservation provided by a quality barrier film ensures better silage, ultimately delivering long-term benefits and cost savings.

Independent research has proven that quality oxygen barriers can provide a return of 6:1 when accounting for reduced dry matter loss alone.

It is generally recommended to use an oxygen barrier film as the initial contact layer directly against the silage surface, and then apply additional protective covers on top.

These extra protective sheets help safeguard the thin oxygen barrier film and underlying silage from damage caused by UV exposure, wind, and rain—particularly in exposed or outdoor conditions—as well as preventing pests and animals from puncturing the cover and contaminating the feed.

Some products, such as Passion Combo, conveniently combine the oxygen barrier and protective layer into a single roll, simplifying installation and speeding up the covering process.

Labour costs to apply silage sheets can make up a considerable proportion of the overall cost of protecting your forage, so reducing labour or maximising the efficiency of the human resources will help to maximise farm profitability. 

Here are a few things you could consider to streamline the cover application process and ensure the job is done right:

Use the right size sheet:  Purchase silage sheets that best fit your silage pit or clamp.  If you get the sizing right, you’ll save time and effort in having to measure, cut and fit the sheets during the covering process.

Invest in high-quality, easy to handle sheets: Choose silage covers that are made from materials that are both durable and lightweight – this will make them easier to handle and position, reducing the physical effort and time required.

Implement a silage applicator or rolling equipment:  Using mechanical applicators and rollers, which can be purchased or rented, will help unroll and position the sheets quickly and evenly, speeding up the silage covering process.

Organise a well-trained team: If this isn’t your first rodeo, you’ll know that team co-ordination is key!  Assignment of tasks (such as one group unrolling whist another secures) can streamline the process, and a well-trained or experienced team will perform tasks more quickly with fewer mistakes. 

Often a contracted team of experienced, specialist labourers can be more cost effective than a novice gang of unskilled and unexperienced labourers and may have the equipment needed as part of their service.

Use weights and gravel bags efficiently: Get pre-filled weights or gravel bags ready and close-by in advance so they can be used as soon as the sheet is in place, reducing the time workers spend moving and filling weights and slowing the whole team operation down.

Work in optimal conditions: Plan around the weather where possible.  A calm dry day will minimise issues caused by wind or rain.  Early morning or evening will reduce worker fatigue when working in hotter climates, enabling a faster pace and less downtime.

Simplify the process: Streamline tasks into simple, repeatable stops.  Use markers to mark the edges or key points of the silage pit in advance to guide the correct placement of sheets, reducing the need for adjustments.

In most cases, yes, but it depends on the type of plastics and local facilities available. 

Recent advances in recycling facilities around the globe are improving the ability to recycle multi-layer films such as the oxygen barrier films.

Cleaning debris, rests of silage, and dirt out of the covers before recycling is usually required, although some facilities do this as part of their service.

You can also consider re-purposing the covers for other on-farm uses such as weed barriers or temporary storage covers to extend their useful life.

Although manufacturing standards are high and defects are uncommon, occasional rips or tears can still occur—either due to accidental physical damage or minor imperfections that can occasionally slip through quality control in high-output production processes.

If your silage cover or oxygen barrier film becomes torn or damaged, immediate action is necessary to prevent oxygen ingress, which could cause spoilage and reduce the quality of your feed.

Carefully assess the damage and promptly repair smaller tears with specialist repair tape, or apply patches for larger areas. In regions subject to increased stress, consider overlapping patches or using double layers for added protection. Placing additional weights over weakened or vulnerable spots can also help prevent further damage.

If you regularly experience tears or damage, you may want to upgrade to a more robust, higher-specification film or consider adding an extra protective layer to enhance durability.

Using a silage wall film can provide benefits that improve the quality and preservation of your silage when using an oxygen barrier film. 

When used in conjunction with an oxygen barrier top cover, silage wall sheets help to create a more airtight seal around the edges and walls, reducing risk of oxygen infiltration from the sides.

Using a silage wall film can significantly improve the quality and preservation of your silage, particularly in larger or more exposed pits. If spoilage and dry matter loss are concerns for your operation, the investment in a wall film could be worthwhile.

Oxygen barrier film is a specialised, multilayer plastic film designed specifically to prevent oxygen from entering silage clamps.

Unlike conventional plastic covers, oxygen barrier films have advanced properties that significantly reduce oxygen permeability, creating an airtight seal that effectively minimises spoilage.

By limiting oxygen exposure, these films greatly reduce mould growth and nutrient losses, resulting in higher-quality feed and improved animal performance.  Financially, this translates into significant cost savings through reduced feed waste and improved productivity.

Additionally, from a sustainability perspective, oxygen barriers lower environmental impact by reducing dry matter loss, which in turn decreases greenhouse gas emissions and maximises the efficiency of inputs such as fuel, fertiliser, and energy invested in forage production.

Oxygen barrier films are designed to provide a much tighter seal against oxygen infiltration. They typically have higher gas impermeability due to their multiple layers and special materials, which can significantly reduce spoilage and improve the quality of the silage.

The primary benefits include:

• Improved silage preservation by minimising oxygen exposure.
• Reduced dry matter loss.
• Reduced top layer spoilage.
• Enhanced feed quality and nutritional value.
• Lower mould and yeast proliferation.
• Increased aerobic stability.
• Potential cost savings by reducing waste and improving feed efficiency.

The permeability of oxygen is measured in terms of oxygen transmission rate (OTR).  The lower the OTR, the lower the permeability of the film, and therefore the better the seal against oxygen. 

You might come across some data or charts on our website that show what looks like a low performance – but a low transmission rate is a good thing, so keep your eye open for OTR and remember the lower the OTR, the better the defence against oxygen.

Correct application of an oxygen barrier film is essential for achieving optimal fermentation and preserving valuable nutrients in your silage. Following these straightforward tips will help ensure your oxygen barrier performs effectively, maximising your forage quality and protecting your investment.

To install oxygen barrier films correctly:

1. Use caution around forage storage areas. Be aware of the potential hazards involved.
2. Prepare the proper surface. Pack as dense and smooth as possible.
3. Unroll the film on the silage.
4. It is easier to cut the film with scissors rather than a knife.
5. When applying, DO NOT pull the film tight; allow it to follow the contours of the silage surface.
6. Overlap joins in the film by at least 1.5m (5ft).
7. Protect Passion Yellow from UV light and physical damage using a solid woven or non woven fabric; protect all other films from physical damage using appropriate covers.
8. Use solid rows of gravelbags to provide an effective SEAL on outside edges and joins.
9. Apply solid rows of gravel-bags every 4m (13ft) across the width and along the length of the silo.
10. At feedout, always keep a solid row of gravel bags on the edge of the film at the feed face.

At Passion Ag, we're committed to helping you get the most from your silage. If you have questions or need advice—whether you're using our products or not—please contact our friendly technical team, who will be happy to support you.

While most oxygen barrier films are designed for single use to ensure maximum effectiveness, some high-quality films may be reused if they are carefully handled and stored. However, reusing the film may compromise its integrity and performance.

There are several types of oxygen barrier films. Some of them are built to be used on their own and others in combination with a UV protected film. Depending on the UV protection level, protective net use, and overall silo management, oxygen barriers should last for the entire duration of the silage storage period, which can be several months up to 1-2 years.

Regardless of the silage storage length, producers should be aware of any damage the cover may sustain during the storage period and take the appropriate measures (taping, resealing, recovering) to guarantee the effectiveness of the seal and silage quality.

Using oxygen barrier films can significantly reduce emissions associated with dry matter loss and spoilage—both of which release harmful greenhouse gases—and also helps prevent the waste of fuel and energy invested in growing and harvesting forage crops. 

Many manufacturers now offer oxygen barrier films that are recyclable and produced from environmentally friendly materials.  Always check with your supplier for detailed environmental information and guidance on responsible disposal or recycling.

The thickness of oxygen barrier films can vary, but typically range between 1.8 to 3.6 mils (45 to 90 microns). The ideal choice depends on the specific conditions and requirements of your silage storage, including handling practices, whether used individually or as part of a combination of layers, and the level of protection needed.

Thinner films often conform more easily to uneven surfaces, helping to effectively cover nooks and crannies. A thicker film doesn't necessarily mean better oxygen barrier performance—this is more influenced by the materials used and the manufacturing process. While thicker films may provide additional strength and resistance to damage, this also depends significantly on the product quality and manufacturer.

When choosing a silage oxygen barrier, it’s best to prioritise proven oxygen-barrier performance and overall material quality, rather than relying solely on thickness as a measure of effectiveness.

Oxygen barrier films can be purchased from agricultural supply stores, online retailers, and dairy and beef cattle consultants.  It’s recommended to compare products and read reviews to select the best option for your needs.

For help to find your nearest distributor or retailer, contact us.

Disposal options include agricultural plastic recycling schemes, where available in your area. If recycling isn't accessible, ensure that films are disposed of responsibly, in line with local regulations and environmental guidelines.

Remember, reusing or repurposing your silage covers around the farm is another great way to reduce waste and maximise their value even further.

Most common issues arise from suboptimal installation, handling-related damage, or insufficient sealing of the film. Regular monitoring of your silage cover and careful adherence to the manufacturer's guidelines for installation, handling, and maintenance can greatly reduce these problems.

In the rare case of a manufacturing defect, contact your supplier immediately and promptly repair the damaged area using appropriate tape or patches. This helps prevent oxygen ingress and protects the long-term quality and nutritional value of your silage.

Effectiveness can be quickly and easily assessed by visually inspecting the silage pile for signs of surface spoilage, mould growth, or evidence of dry matter loss and shrinkage.

It's good practice to inspect silage covers for rips or tears at least once a week, particularly during periods of frequent handling or adverse weather. Additionally, conduct an immediate inspection after any significant weather events (such as storms, heavy winds, or hail) and whenever the silage clamp is opened or disturbed.

Additionally, new digital tools and remote sensors are becoming available, offering continuous monitoring of temperature and humidity within the silage pile. These devices can automatically alert you to potential issues early, allowing you to take prompt corrective action.