The value for pasture rental rates using the AUM method can be highly variable and driven by supply and demand. Little to no survey data is available in North Dakota that provides an average or most frequently used AUM rate. However, once you have calculated your rental rate by the acre, you can convert that value to an AUM rate.
Calculating the AUM rate requires that the average carrying capacity for your pasture be determined. For landowners who do not know the carrying capacity of their pasture or rangeland, Table 3 is included to provide an estimated stocking rate guide for different regions (see Figure 1 for multiple land resource areas) of North Dakota.
The landowner and tenant agree upon a per-acre rental rate and determine total payment for pasture using the assumption the livestock will graze for the entire planned grazing season (even if they don’t). Then the landowner estimates the carrying capacity of the pasture to be rented. Determining actual carrying capacity using a current or past conservation plan is highly recommended.
The landowner must categorize all acres within the pasture by upland and lowland vegetation types (also includes soil type). Each vegetation type is multiplied by the recommended stocking rate from Table 3 to determine AUMs available. Finally, you divide total payment by AUMs available in the pasture to determine AUM rental rate.
By using this value, the tenant only pays for the number of animal units grazed for the given time period. Refer to NDSU Extension publication “Determining Carrying Capacity and Stocking Rates for Range and Pasture in North Dakota” for more information on estimating carrying capacity.
Table 3. Estimated carrying capacity guide in animal unit months per acre (AUM/ac) by site and multiple land resource areas (MLRA) for reference plant communities2.
Vegetation Type |
53A&B |
54 |
55A&B |
56 |
58C&D |
Upland Loamy |
0.66 |
0.66 |
0.71 |
0.85 |
0.57 |
Upland Sandy |
0.68 |
0.66 |
0.77 |
0.85 |
0.55 |
Upland Clayey |
0.63 |
0.57 |
0.66 |
0.82 |
0.52 |
Upland Shallow |
0.60 |
0.38 |
0.52 |
0.60 |
0.36 |
Upland Very shallow/Thin claypan |
0.30 |
0.24 |
0.37 |
0.43 |
0.22 |
Lowland Overflow |
0.96 |
0.87 |
1.01 |
1.15 |
0.57 |
Lowland Wet meadow |
1.23 |
1.16 |
1.28 |
1.37 |
0.92 |
2 Animal unit months/acre by vegetation type are based on a 0.25 harvest efficiency.
Carrying capacity formula: # of acres x Recommended AUM/ac = AUMs (Table 3) (Repeat for all vegetation types)
AUM rental rate formula: Total payment based on agreed per-acre rental rate ÷ Total AUMs from combined vegetation types using carrying capacity formula = AUM rate
Recommended head to graze formula: Total AUMs ÷ Months of planned grazing = Max. # of animal units to graze
Figure 1. Major land resource areas of North Dakota.
Example 1
1,000-acre pasture in Mercer County (MLRA 541) with an agreed rental price of $17.30/acre for a total payment of $17,300. The planned grazing season is May 15 – Nov. 1 (5.5 months). Pasture contains 70 % sandy vegetation type, 20 % shallow vegetation type and 10 % overflow vegetation type.
Sandy: 700 acres x 0.66 AUM/ac2 = 462 AUM
Shallow: 200 acres x 0.38 AUM/ac2 = 76 AUM
Overflow: 100 acres x 0.87 AUM/ac2 = 87 AUM
Total: 625 AUM
Rental rate = $27.68/AUM ($17,300 ÷ 625 AUMs)
Number of recommended animal units (AU) = 113.6 AU (625 AUM ÷ 5.5 months)
Number of recommended 1,200-pound cows with calves = 99 head (113.6 AU ÷ 1.15 AUE3 - 1,200-pound cow with calf) for 5.5 months
1 Shown in Figure 1.
2 Taken from Table 3.
3 Taken from Table 2.
Example 2
1,000-acre pasture in Ransom County (MLRA 55B1) with an agreed rental price of $31.10/acre for a total payment of $31,100. The planned grazing season is May 15 – Nov. 1 (5.5 months). Pasture contains 70 % sandy vegetation type, 20 % shallow vegetation type and 10 % overflow vegetation type.
Sandy: 700 acres x 0.77 AUM/ac2 = 539 AUM
Shallow: 200 acres x 0.52 AUM/ac2 = 104 AUM
Overflow: 100 acres x 1.01 AUM/ac2 = 101 AUM
Total: 744 AUM
Rental rate = $41.80/AUM ($31,100 ÷ 744 AUMs)
Number of recommended animal units (AU) = 135.3 AU (744 AUM ÷ 5.5 months)
Number of recommended 1,200-pound cows with calves = 118 head (135.3 AU ÷ 1.15 AUE3 - 1,200-pound cow with calf) for 5.5 months
1 Shown in Figure 1.
2 Taken from Table 3.
3 Taken from Table 2.