April 28th - 2021

Silage production Part 5

COVERING

The crop is finally in the clamp, now the important bit, sealing it in to preserve as much of the DM and nutrients as possible to be ready to feed out over the Winter.

- Cover silage with a combination of Silostop oxygen barrier film, re-usable covers, and gravel bags to minimise top surface spoilage losses, improve hygienic quality and aerobic stability.

- Polyethylene (PE) film, typically 125 µm in thickness and weighted with discarded car or truck tyres or tyre sidewalls, has been the common system used to protect the top surface of silos and piles. But the level of protection provided is highly variable and often changes during storage. Standing water in full-casing tyres can spread the West Nile virus and harbour snakes.

Minimize top layer spoilage in bunkers and drive-over piles.

- Achieve a target density of 700 kg fresh weight (220 kg DM)/m³ in the top 0.75 to 1.0 metre.

- Shape the top surface convex so water drains off the bunker or pile; the back, front, and sides of piles should not be steeper than a 1 in 3 slope.

- Apply covers immediately after filling is completed.

- A layer of oxygen barrier (OB) film and a sheet of white on black PE plastic or anti-UV cover are more effective at preventing surface spoilage than single or double sheets of conventional PE plastic (see Table).

Average losses, inedible silage and aerobic stability of the top layer stored
in bunkers and piles under either conventional film or Silostop OB film.

- Overlap the sheets by a minimum of 1.0 to 1.5 metres. If overlap is less than 1 metre, use Silostop Silopatch to ensure joins are airtight.

- Arrange overlapping sheets so run-off water does not come into contact with the silage.

- Sheets should reach 1.0 to 1.5 metres from the forage surface around the perimeter of drive-over piles.

Ensure that the correct sheet is being used

- Silostop Orange is ideal for single cut systems such as maize and whole crop.

- Max is perfect for multi-cut systems as it is robust and strong allowing it to be open and closed multiple times without damaging the sheet, examples of these would be multi-cut grass systems.

- Max Plus with large exposed piles when no net or cover is used, reducing labour costs. It’s frequently used with all silo systems.

- Put an anti-UV cover or protective Nets on top of Silostop OB film sheets.

Choosing the right cover is key to allow the OB films to perform at their best.

- SupaCova Anti-UV, used alongside Silostop Orange. This 98% shade net prevents UV rays from damaging the film and maintains a physical barrier against vermin and other damages.

- SupaCova Premium Net used with Max. Its strong knitted structure protects the sheet from physical damage.

Put uniform weight on all covering materials over the entire outer surface and double or triple the weight where sheets overlap.

- Gravel bags can be placed on pallets and lifted easily to the top of the silo wall when the forage surface is being covered. They don’t harbour dirty water or wire which are often problems found when using tyres.

- Gravel bags can be placed on pallets and lifted easily to the top of the silo wall when the forage surface is being covered.

- A 15 to 30 cm layer of sand and/or soil or gravel bags placed end to end is an effective way to anchor sheets around the perimeter of drive-over piles.

- Mow the area surrounding a bunker or pile and put up temporary fencing to protect against domesticated and wild animals.

- Avoid spraying herbicides near silos because they may accelerate film degradation.

- Store weighting materials so they do not harbour vermin.

- Inspect and repair covers frequently during the storage period to minimise spoilage due to physical damage.

- Spoiled silage, contaminated, discoloured, or inedible material has a negative effect on silage intake, digestibility and animal health and should not be used as animal feed.

Tim Brewer