Estimate how many grazing days your pasture can support based on acreage, forage production, and herd size.
Try it out
Load example pasture carrying capacity estimator data to see the full workflow
Contact your local extension office for regional estimates
Typically 25\u201335% for continuous grazing
Dry matter intake, typically 2.0% BW
Moderate grazing capacity. Supplement with hay when forage is depleted. Use rotational grazing with rest periods of 30+ days.
Based on NRCS carrying capacity concepts and SDSU Extension grazing calculations. Actual forage availability varies with soil type, rainfall, season, and management. Contact your local extension office for site-specific recommendations.
How It Works
This calculator uses forage budgeting to estimate how long your pasture can sustain your herd. Grazing days equals (acres times forage lb/acre times efficiency%) divided by (horses times weight times DMI%). Forage production varies widely by region and grass type (1,500–6,000+ lb/acre); your local extension office can provide estimates. Harvest efficiency represents the fraction of forage actually consumed: 25–35% for continuous grazing, 50–70% for rotational grazing. Horses typically consume 2.0% of body weight in dry matter per day (DMI). The calculator also shows current stocking density; below 1.5 acres/horse, pastures are typically overstocked for continuous grazing.
Rotational Grazing Tips
Divide pasture into 3–4 paddocks of equal size. Rotate when grass is grazed to 3–4 inches (never below 2 inches). Allow 30+ days of rest per paddock before re-grazing. Use a sacrifice paddock (dry lot) during wet seasons or dormancy. Drag or harrow paddocks after grazing to break up manure piles. Soil test annually and fertilize based on results. Overseed bare or thin areas in spring or early fall.
Overgrazed pastures lose protective ground cover, allowing weeds and erosion. Bare soil compacts under hooves, reducing water infiltration and forage regrowth. Recovery from severe overgrazing can take 2–3 growing seasons and cost 400/acre in reseeding alone. Rotational grazing and proper stocking rates are the most cost-effective pasture management practices available to horse owners.
