Forage Yield Calculator
Measure forage dry matter yield per hectare using the quadrat cutting method. Estimate total pasture production and carrying capacity.
Results
How to Use This Calculator
Cut and weigh all forage in a measured quadrat. Enter quadrat width and length in meters, fresh sample weight in grams, dry matter percentage, and total field area in hectares. Click Calculate.
About This Tool
The Forage Yield Calculator uses the standard quadrat method recommended by extension services. Forage DM yield drives stocking rate, hay production estimates, and pasture management decisions. NRC and FAO provide guidance on sampling methodology.
Applicability: This calculator is designed for global livestock operations, with particular relevance for North American and European cattle, pig, and poultry farms.
How the Calculation Works
Sample area = width × length (m²). Fresh yield/ha = (sample weight g ÷ sample area m²) × 10,000 ÷ 1,000 (g to tonnes). DM yield = fresh yield × DM%. Total DM = DM yield/ha × field area. Take 5-10 quadrats per field for reliability.
Real-World Example
Quadrat 0.5×0.5 m = 0.25 m². Sample = 500 g. Fresh yield = 500/0.25 × 10,000/1,000 = 20,000 kg/ha = 20 t/ha fresh. At 25% DM = 5 t DM/ha. 10 ha = 50 t DM total. Carrying = 50,000 kg ÷ (12 kg × 365) = 11.4 cow-years.
Common Mistakes & Tips
Common mistakes: taking only one quadrat (use 5-10 samples), not drying sample for accurate DM%, measuring unrepresentative patches. Tip: sample at grazing height, not tallest grass. DM% can be estimated by feel or measured with a microwave/oven. Consult extension for local benchmarks.
Reviewed by Agricalc Editorial Team — Agricultural engineers and agronomists with 10+ years of field experience. Our team verifies every calculator formula against peer-reviewed extension publications. For site-specific advice, consult your local agronomist.
References
Frequently Asked Questions
How do I use the quadrat method?
Cut all forage within a measured frame (typically 0.25-1 m²) at grazing height. Weigh immediately for fresh weight. Take a sub-sample of ~100-200 g, dry in oven at 60°C for 48 hours, reweigh for DM%. Repeat 5-10 times across the field. Average the results. Extension services recommend 10 quadrats per management unit.
What is a good forage yield per hectare?
Yields vary widely: permanent pasture 3-6 t DM/ha/year, improved pasture 8-15 t DM/ha, irrigated or high-input forage 15-25 t DM/ha. Annual: warm-season grasses peak in summer, cool-season in spring/fall. NRC and extension publications provide regional benchmarks.
How do I estimate dry matter percentage?
DM% can be estimated by: (1) Oven drying — most accurate (60°C, 48h), (2) Microwave method for quick estimates, (3) Feel and appearance — lush grass ~20-25% DM, wilting ~35-45%, cured hay ~85-90% DM. For critical decisions, use lab analysis. FAO recommends lab testing for precision ration balancing.
How many animals can my pasture support?
Carrying capacity = total DM produced ÷ (daily DM intake × days). Example: 5 t DM/ha × 10 ha = 50,000 kg DM. At 12 kg/day per cow = 4,167 cow-days ÷ 365 = 11.4 cow-years. Adjust for pasture utilization (50-70%) — animals don't graze everything. Leave 30-50% residual cover.
When should I sample forage yield?
Sample at typical grazing height, not at maximum growth. For rotational grazing, sample just before each paddock graze. For hay, sample at boot/early head stage. Sample at the same time of day to avoid moisture fluctuations. Record weather conditions. Extension recommends sampling every 2-4 weeks during growing season.
