Forage Yield Calculator
Convert a clipped hoop sample or a grazing stick reading into pounds of dry matter per acre.
Your numbers
Dry matter production from the clipped sample
1,800 lb DM/acre
- As-fed (wet) yield
- 6,000 lb/acre
- Standing crop
- 0.90 tons DM/acre
- Dry weight of sample
- 36.0 g
- Average at least five samples per pasture. One hoop toss measures the spot, not the field.
- Clip to your intended residual height, not to bare soil, if you want the available rather than total yield.
Show the math
- Dry weight of the sample120 g × 30% DM = 36.0 g
- Convert to pounds36.0 g ÷ 453.59 g/lb = 0.079 lb
- Scale-up factor43,560 ft²/acre ÷ 1.92 ft² sample = 22,688×
- Dry matter per acre0.079 lb × 22,688 = 1,801 lb DM/acre
Assumptions this calculator used
Nothing here is hidden. Change any figure you have better local data for.
- 43560 ft²
Fixed conversion used to scale the sample up to an acre. Source: US customary units.
- 453.592 g
Fixed conversion for scale readings taken in grams. Source: US customary units.
How to calculate forage yield
Every grazing number downstream — stocking rate, grazing days, paddock size — rests on pounds of dry matter per acre. Measuring it is a two-step conversion: take the dry weight of a small known area, then scale that area up to an acre.
lb DM/acre = (fresh grams × DM% ÷ 453.6) × (43,560 ÷ sample ft²)
Worked example
A 1.92 ft² hoop clipped to 3 inches yields 120 g fresh. At 30% dry matter that is 36 g dry, or 0.079 lb. An acre holds 22,688 of those hoops, so the pasture is carrying about 1,800 lb DM/acre above the residual — the number you would feed into a grazing days or stocking rate run.
Common mistakes
- Sampling where the grass looks best. Throw the hoop over your shoulder without looking, and take a lot of them.
- Reporting wet weight as yield. Spring grass is 75-80% water. Not converting to dry matter overstates the pasture by four times.
- Clipping to the ground. That measures total biomass, not what cattle can take.
- Using one stick factor for every paddock. A renovated bermuda field and a thin native hillside do not share a density.
Pounds of dry matter per acre by forage species
Typical annual production under average moisture and management, plus the pounds of dry matter per acre-inch used for grazing stick readings.
| Forage species | Annual yield (lb DM/acre) | lb DM per acre-inch | Typical DM at grazing |
|---|---|---|---|
| Bermudagrass, fertilized | 6,000-10,000 | 350-450 | 30-35% |
| Bermudagrass, unfertilized | 2,500-4,000 | 250-350 | 30-35% |
| Tall fescue (KY-31) | 3,500-6,000 | 250-350 | 22-28% |
| Orchardgrass | 3,000-5,000 | 220-300 | 20-26% |
| Smooth bromegrass | 3,000-4,500 | 230-300 | 24-30% |
| Bahiagrass | 3,000-5,000 | 250-350 | 28-34% |
| Alfalfa-grass mix | 4,000-7,000 | 350-500 | 20-25% |
| Annual ryegrass | 3,500-6,000 | 200-280 | 18-24% |
| Cereal rye / wheat pasture | 2,000-4,000 | 180-250 | 15-22% |
| Native tallgrass prairie | 3,000-5,000 | 200-300 | 35-45% |
| Native mixed-grass prairie | 1,200-2,500 | 150-250 | 40-55% |
| Native shortgrass prairie | 600-1,500 | 120-200 | 45-60% |
| Sorghum-sudangrass | 5,000-9,000 | 300-450 | 18-25% |
| Stockpiled fescue (winter) | 1,500-3,000 | 250-350 | 50-70% |
Calculators to run next
- Paddock Size CalculatorUse when you are subdividing ground and need acres per break and paddock count.
- Pasture Rest Period CalculatorUse when regrowth is falling short and the rotation needs to slow down.
- Acreage CalculatorUse when you need the acreage of an odd-shaped field before any forage math.
- Stocking Rate CalculatorStart here when the question is how many cows the whole place will run for a season.
- Animal Unit Equivalent CalculatorUse when the herd is mixed, so one number stands in for every class on the place.
- Grazing Days CalculatorUse when the herd is already in the paddock and you need a move date.
Guides that use this calculator
- How Many Cows Per Acre: Working Out Stocking Rate HonestlyCows per acre is an output, not an input. Here is the dry matter arithmetic behind it, the utilization rate most people get wrong, and honest numbers by region.
Questions ranchers ask
How do I clip a forage sample correctly?
Toss a hoop or square of known area at random into a representative part of the pasture — never picking the good spot or the bare spot. Clip everything inside it to your intended grazing residual height, not to the ground. Bag it, weigh it fresh, dry it, and weigh it again. Take at least five to ten samples per pasture and average them; a single sample tells you almost nothing.
What size hoop should I use?
A 1.92 ft² hoop (18.75 in diameter) is the classic choice because grams of fresh weight convert to pounds per acre with a simple factor. A 0.25 m² quadrat or a 2 ft × 2 ft square works equally well — this calculator handles any area you enter.
How do I dry the sample without a lab oven?
A food dehydrator at 130-140 °F overnight, a microwave with a cup of water present in short bursts, or a paper bag in a truck dash in July all work. Dry until two consecutive weighings match. Alternatively skip drying and use a typical dry matter percentage — 20-25% for lush spring growth, 35-45% for summer growth, 85-90% for standing dormant forage.
What is a grazing stick and is it accurate enough?
A grazing stick is a yardstick printed with pounds of dry matter per acre per inch for common forage types. It is less accurate than clipping — typically within 15-25% — but it takes seconds instead of a day, so people actually use it. Calibrate it once against clipped samples on your own pastures and it becomes genuinely useful.
How many pounds of dry matter is one inch of pasture?
It depends on density as much as species. Thin, stemmy stands run 150-200 lb DM/acre-inch. Good cool-season pasture with full sod runs 250-350. Dense bermudagrass or a thick alfalfa-grass mix can reach 400-500. Density matters more than height, which is why walking the pasture beats eyeballing it from the truck.
Should I measure total yield or available yield?
For stocking rate planning, measure total annual production and apply a utilization rate. For a move decision today, measure only the forage above your residual target. Mixing the two is how paddocks get grazed to dirt on paper-perfect plans.
Does fertilizer change the yield much?
Substantially on introduced species. Fifty units of nitrogen on bermudagrass or fescue commonly adds 1,000-2,000 lb DM/acre if moisture is there. On native rangeland the response is small, inconsistent, and often shifts the plant community toward weeds, which is why most range managers do not fertilize native ground.
How often should I re-measure?
Once per rotation on the paddocks you are about to graze during the growing season, and once at peak standing crop for annual production records. Keeping three years of peak-standing-crop numbers is worth more than any published average for your county.
Measured more grass than you are using?
Surplus forage is only worth something if it goes through an animal. Agrilot's auctions are a straightforward way to add documented cattle — registered Angus females and bulls, each with an AI condition report — to put the extra production to work rather than letting it go to seed.