Silage Face Removal & Cut Back Fast Enough to Stay Fresh
Feeds out grass
Daily demand ÷ density gives the volume removed; over the exposed face it becomes cm/day, and at least 15 cm/day keeps spoilage in check — enter the herd, intake, density and face size to check yours.
Size your silage face
Next: you're advancing 20.5 cm/day — keep the face tight and clean to hold freshness through the season.
Rule of thumb: ≥15 cm/day in winter and ~30 cm/day in summer keeps the cut face ahead of aerobic spoilage. A face that sits too long heats up and loses dry matter and palatability.
Silage face removal — key facts
- Daily demand
- herd × intake/head
- Volume/day
- demand ÷ density
- Removal rate
- (volume ÷ face area) × 100
- Adequate
- ≥ 15 cm/day
- Warm weather
- up to 30 cm/day
- Slow face risk
- heating, spoilage, DM loss
- Speed it up
- narrower, taller face
- Privacy
- Runs in your browser; nothing uploaded
Beat the air across the face
The moment a silage face meets air, yeasts and moulds start respiring it — the face heats, dry matter burns off and feed value falls. The defence is speed: the faster you cut back across the whole face each day, the less time any silage sits exposed before it is eaten. A wide, low clamp feeding a small herd advances slowly and is the classic cause of summer heating and waste at the face.
This tool turns the herd, daily intake, clamp density and face size into a cm/day face-advance rate and tells you whether it clears the 15 cm/day spoilage threshold. If it falls short, narrow the face or split the clamp. Pair it with the Silage Loss and Silage Pit Capacity tools to design and feed the clamp end to end.
Stop the face heating
Check the advance clears 15 cm/day.
Size the clamp right
Match face width to herd at the design stage.
Cut feed-out waste
Less exposure means less spoiled silage.
Instant verdict
An adequate flag, not just a number.
Frequently Asked Questions
How is the face removal rate calculated?+
First the daily demand: herd size × intake per head. Divide that by the silage density to get the volume removed each day, then spread that volume over the exposed face area (width × height) and convert to centimetres: removal rate = (daily demand ÷ density ÷ face area) × 100. So 50 cows eating 12 kg/head from a clamp at 200 kg/m³ over a 4 m × 2 m face advance (600 ÷ 200 ÷ 8) × 100 ≈ 38 cm/day.
What removal rate is adequate?+
The tool flags 15 cm/day or more as adequate — that is the widely used rule for keeping a silage face ahead of aerobic spoilage in temperate conditions, with up to 30 cm/day advised in warm weather. Below 15 cm/day the face sits exposed too long, heats and spoils. The calculator tells you straight away whether your rate clears the bar.
Why does a slow face spoil silage?+
Once silage is exposed to air, yeasts and moulds start respiring sugars and acids, the face heats, and dry matter and feed value are lost. The faster you cut back across the face, the less time any given silage spends exposed before it is fed. A slow face on a wide, low clamp is the classic recipe for visible heating and waste.
How do I speed up a slow face?+
The cheapest fix is a narrower, taller face — the same daily tonnage over a smaller area advances faster. You can also fill the clamp narrower when building it, split a wide clamp lengthways and feed one half at a time, or simply match clamp width to herd size at the design stage. Keep the face clean and tight, not loosened and ragged.
Does the clamp density matter?+
Very much. A well-compacted, dense clamp holds more dry matter per cubic metre, so the same daily demand removes less volume — and the face moves a little slower for a given tonnage. But dense silage also resists air far better, so a slightly slower face on a tight clamp can still stay fresh. Loose, under-compacted silage is the real spoilage risk.
Does this work for bales as well as clamps?+
The tool is built for clamp and bunker faces, where a flat exposed face advances over time. Baled silage works differently — each bale is sealed until opened and should be fed within a day or two of opening. For clamps and drive-over piles, the cm/day face advance is the right measure.
What if my face is too wide?+
A wide, low face is the most common cause of slow removal and summer heating. If the rate comes back below 15 cm/day, the clamp is wider than your herd needs. Feed across only part of the width, build narrower next season, or increase intake/herd on that clamp — anything that lifts the cm/day back above the threshold.
Is the threshold a hard rule?+
15 cm/day is a sound, widely cited minimum, not an absolute — warm weather, loose silage and high yeast counts all demand a faster face, while cold weather and dense, well-sealed silage tolerate a little less. Use the calculated rate and the adequate flag as a design and management guide, and watch the face itself for heating and visible spoilage.