Interactive Tools for Grazing
Pasture Management Workbook
Here is a collection of calculators for use in your grazing management decisions.
Table 1: Tame pasture condition class definitiions
Different classes are identified for four main pasture conditions found in Alberta. These help determine what your stocking rate will be in Table 2.
| Category | Excellent | Good | Fair | Poor |
|---|---|---|---|---|
| Potential yield for the area | 75 to 100% | 60 to 75% | 50 to 60% | 33 to 50% |
| Production that comes from desirable, adapted species including legumes | 95% | 90% | 60% | <50% |
| Production that comes from weeds or undesirable plants | <5% | <10% | >20% | >50% |
| Fertility program | Average to above average | Average | Below average of non-existent | None |
Table 2: Estimated forage production based on tame pasture condition
Four different classes (from Table 1) contain the estimated forage production (in lb/acre) class typically for hay production, and for the estimated carrying capacity (in AUM/acre) for tame pastures in Alberta.
| Annual Precipitation Zones | Pasture Condition Class | |||||||
|---|---|---|---|---|---|---|---|---|
| mm (inches) | Excellent | Good | Fair | Poor | ||||
| AUM/acre | Forage Production Hay (lb/acre) | AUM/acre | Forage Production Hay (lb/acre) | AUM/acre | Forage Production Hay (lb/acre) | AUM/acre | Forage Production Hay (lb/acre) | |
| 250 to 350 (10 to 14) | 0.75 | 700 | 0.50 | 460 | 0.40 | 370 | 0.25 | 230 |
| 350 to 450 (14 to 18) | 1.25 | 1,150 | 0.80 | 740 | 0.60 | 550 | 0.40 | 370 |
| 450 to 550 (18 to 22) | 2.00 | 1,850 | 1.40 | 1,300 | 1.10 | 1,000 | 0.70 | 650 |
| 550 to 650 (22 to 26) | 3.30 | 3,000 | 2.20 | 2,000 | 1.60 | 1,500 | 1.10 | 1,000 |
| Irrigation | 7.50 | 6,000 | 5.00 | 4,600 | 3.75 | 3,500 | 2.50 | 2,300 |
Table 3: Animal Unit Equivalents (AUEs) of various grazing livestock species and their classes
There are six different species of grazing livestock typically raised in Alberta. Their average weight and expected daily intake (in % body weight and forage dry matter (DM) per day) are recorded below.
| Livestock Species | Weight (lb) | % Intake of Body Weight | Forage DM Intake (lb/day) | AUE |
|---|---|---|---|---|
| Cattle | ||||
| Weaned calf | 500 | 2.5 | 12.5 | 0.50 |
| Yearling | 750 | 2.5 | 18.8 | 0.75 |
| Small mature cow with or without calf (beef) | 1,000 | 2.5 | 25.0 | 1.00 |
| Large mature cow with or without calf (beef) | 1500 | 2.5 | 37.5 | 1.50 |
| Small mature bull | 1500 | 2.5 | 37.5 | 1.50 |
| Large mature bull | 2200 | 2.5 | 55.0 | 2.20 |
| Dairy cow (lactating) | 1500 | 3.0 | 45.0 | 1.50 |
| Horses | ||||
| Yearling | 500 | 2.5 | 12.5 | 0.50 |
| Two-year-old | 700 | 2.5 | 17.5 | 0.70 |
| Small 3-yr-old and older | 1,000 | 2.0 | 20.0 | 1.00 |
| Large 3-yr-old and older | 1,500 | 2.0 | 28.0 | 1.50 |
| Adult draft | 2,500 | 2.0 | 50.0 | 2.50 |
| Sheep & Goats | ||||
| Weaned lamb/kid | 75 | 3.5 | 2.6 | 0.08 |
| Ewe or doe with/without lamb or kid (meat or non-dairy) | 150 | 2.5 | 3.8 | 0.150 |
| Lactating dairy ewe or doe | 150 | 4.0 | 6.0 | 0.150 |
| Ram or buck | 200 | 3.0 | 6.0 | 0.200 |
| Deer | ||||
| All sexes | 200 | 3.0 | 6.0 | 0.20 |
| Bison | ||||
| Yearling | 700 | 2.5 | 17.5 | 0.70 |
| Cow | 1,000 | 2.5 | 25.0 | 1.00 |
| Bull | 2,000 | 2.5 | 50.0 | 2.00 |
| Elk | ||||
| Yearling | 350 | 3.0 | 10.5 | 0.60 |
| Cow with or without calf | 550 | 2.50 | 13.8 | 0.55 |
| Bull | 750 | 2.5 | 18.8 | 0.75 |
Source: Adapted from Alberta Agriculture Beef Cow-Calf Manual or Alberta Forage Manual (Table 35, page 203), Alberta Agriculture Nutrition and Feeding Management for Horse Owners, Alberta Lamb Producers Managed Grazing for Sheep & Goat Producers factsheet, Canadian Bison Association Bison Pastures factsheet, and Range University factsheet on Calculating Intake Based on Animal Demand
Table 4: Average stocking rate for loamy ecosites in each ecoregion
Climatic Moisture Index is defined as annual precipitation minus annual potential evapotranspiration.
Positive numbers indicate an excess of precipitation over evaporation, as occurs in moist forest climates. Negative numbers indicate drier grassland climates, in which there is less moisture from precipitation than could potentially be evaporated.
The study took data from loamy ecosites because they tended to prove more reliable data consistency due to the reduced chance of site variation.
| Ecoregion | Climatic Moisture Index (mm) | AUM/ac |
|---|---|---|
| Dry Mixed Grassland | below -325 mm | 0.2 |
| Mixed Grassland | -325 to -225 mm | 0.29 |
| Aspen Parkland, drier portion | -225 to -125 mm | 0.44 |
| Aspen Parkland, moister portion | above -125 mm | 0.68 |
Forage Yield Calculator
Guides you in calculating your pasture forage yield using two ways: estimate by pound-per-acre-inch, or by punching in the numbers from performing field sampling in your pastures.
Stocking Rate Calculator
Tells you how many animal unit months you can have per acre, and use that to determine how many animals you need for your pasture, or how much pasture you need for your animals.
Stock Density Calculator
Total liveweight calculated per paddock based on herd size, animal weights, and paddock size. Ideal for use in ultra-high-stock density grazing systems, or just for curiousity.
Pasture Paddock Planning Calculator – Livestock Needed
Highly detailed calculator for management-intensive or AMP grazing. Helps determine the number of animals you need based on pasture size, forage yield, and utilization rate.
Pasture Paddock Planning Calculator – Acres Needed
Highly detailed calculator for management-intensive or AMP grazing. Helps determine the number of acres needed for a pasture based on the size, weight, and number of animals being grazed.
Pasture Paddock Planning Calculator – Time per Paddock
Highly detailed calculator for management-intensive or AMP grazing. This will help you show how much time your animals need to stay in a paddock based on herd size, forage yield, and utilization rate.