🏺 Silage Preparation Calculator — Bunker Size & Plastic

Calculate silage bunker/pit size requirements, plastic cover area, and total tonnes from crop yield. Plan silage season effectively.

Quick answer: Grass silage: 20-35 t fresh/ha. Maize silage: 35-60 t fresh/ha. Bunker size (m³) = Tonnes ÷ 0.7 density. Plastic = (L×W×2) + (L×H×2) + (W×H×2) + 20% overlap.

🏺 Calculate Silage Requirements

Total fresh silage to store
Available bunker width
Fill height — max 4m for safety
Bunker Length Required (m)
Bunker Volume (m³)
Plastic Cover Area (m²)

📐 How Silage Bunker Is Calculated

Volume required = Tonnes ÷ Density (t/m³)
Length = Volume ÷ (Width × Height)
Plastic = (L×W×2)+(L×H×2)+(W×H×2) × 1.2

📊 Worked Example

200 tonnes grass silage (0.65 t/m³). Bunker width 5m, height 3m.

Volume = 200 ÷ 0.65 = 308 m³
Length = 308 ÷ (5 × 3) = 20.5 m
Plastic = approx 250 m²

❓ Frequently Asked Questions

Volume (m³) = Tonnes ÷ Density (0.65-0.75 t/m³). Length = Volume ÷ (Width × Height). Height limit 3-4m for safety.

Grass silage: 20-35 t fresh/ha. Maize silage: 35-60 t fresh/ha. Pasture silage: 12-25 t fresh/ha.

Plastic area = Surface area × 2 + 20% overlap. 15m × 5m bunker needs ~150m² plastic. Add 1m on each side for sealing.

Minimum 6 weeks before feeding. Optimum 8-12 weeks. Once opened, feed out at 10-15cm per day to prevent spoilage.

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