When it comes to making high-quality silage, there are a lot of decisions that go into the final product.
But Dairy Australia has recommended five key tips to encourage a quality product — cut pastures early, wilt quickly and harvest as soon as possible, compact forage as densely as possible, seal quickly and well to exclude air and repair holes immediately using specific silage tape.
Cut early in the season
For maximum silage quality, cut pastures when they are at or near canopy closure.
This is also the optimum stage of growth for grazing in spring.
Providing pasture is at or only slightly past grazing height, and harvested in good weather conditions, milk production will be only marginally less than if the same pasture had been grazed by the cows.
Wilting rate of the mown pasture has a big impact on silage quality and is impacted by the time of day the silage is cut.
To avoid overdrying, mow after dew has lifted, match mowing and harvesting operations, so that mown material is not left unharvested for lengthy periods, delay mowing until mid to late afternoon to reduce the risk of overdrying the forage during hot, dry and windy weather, and stagger mowing and narrow the swath width if there is a real risk of over-drying.
Wilt and harvest quickly
Have the forage in the pit or bale within 24 to 48 hours, if possible
Wilt rapidly to the target dry matter (baled silage 40 to 50 per cent and pit silage 32 to 38 per cent) to reduce potential dry matter and quality losses.
Keep it compact
Compact stacks and make bales as dense as possible.
The better the compaction, the less air will be trapped in the stack or bale, resulting in a higher-quality silage.
Seal airtight as soon as possible
Seal stacks, don’t just cover them.
Finish rolling immediately after harvest is completed and avoid rolling the next morning as this just pumps more oxygen into the stack.
Rolling should keep up with forage delivery from the paddock.
Seal pits or stacks as soon as harvest is complete.
If leaving overnight minimise air getting into the stack by placing plastic on the stack and weighing down the edges.
Finish weighing down the stack next morning and ensure seals are airtight.
For an airtight seal use gravel bags, filled with pea gravel or washed sand, along bunker walls and stack surface. Even a double row of tyres around the perimeter does not achieve an airtight seal.
Repair holes immediately
Maintain silage quality by repairing holes as soon as possible and ensure the area to be patched is clean and dry.
Use specific silage repair tape of similar colour to the holed plastic. This minimises the difference in contracting and expanding in hot/cool conditions and stops the seal leaking.