Silage Bunker Tonnage and Density Calculator
Calculate silage bunker tonnage from face dimensions, density and depth, for feed inventory and packing decisions.
How This Calculation Works
Silage tonnage equals the bunker volume in cubic feet times the density in pounds per cubic foot, divided by 2,000. Volume is length times width times depth. A well-packed corn silage runs about 40 to 45 pounds per cubic foot, while poor packing drops to 30 or less.
Field Calibration & Rate Reference Chart
| Area | Square feet | Acres | Square field side |
|---|---|---|---|
| 1,000 sq ft | 1,000 | 0.023 | 32 ft |
| 5,000 sq ft | 5,000 | 0.115 | 71 ft |
| 10,000 sq ft | 10,000 | 0.230 | 100 ft |
| 0.25 acre | 10,890 | 0.250 | 104 ft |
| 0.5 acre | 21,780 | 0.500 | 148 ft |
| 1 acre | 43,560 | 1.000 | 209 ft |
| 5 acres | 217,800 | 5.000 | 467 ft |
| 10 acres | 435,600 | 10.000 | 660 ft |
| 40 acres | 1,742,400 | 40.000 | 1,320 ft |
| 100 acres | 4,356,000 | 100.000 | 2,087 ft |
Common Questions
How do I calculate silage tonnage in a bunker?
Multiply the bunker volume in cubic feet by the density in pounds per cubic foot, then divide by 2,000. A 100 by 40 by 10 foot bunker at 40 pounds per cubic foot holds about 800 tons. Density depends on packing.
What is a good silage packing density?
Aim for at least 40 to 45 pounds per cubic foot for corn silage and 35 to 40 for haylage. Poor packing below 30 pounds per cubic foot leads to spoilage and shrink. Pack in thin layers with a heavy tractor.
How much silage does a cow eat per day?
A lactating dairy cow eats 60 to 80 pounds of silage per day as part of a total mixed ration. Dry cows and heifers eat less. Match the feed-out rate to the herd so the face stays fresh.
How deep should I remove silage from the face?
Remove at least 6 inches from the face each day in cool weather and 12 inches or more in warm weather to prevent heating and spoilage. A smooth, tight face limits air penetration. Keep the face straight and clean.