Direct Conversion Table for AUM/Ac and Ac/AUM

This table is a direct conversion chart for determining Acres per Animal Unit Month and Animal Unit Months per Acre. Barry Wallace, Area Range Conservationist, developed this table in whole acres to supplement the Feed Conversion to Animal Unite Months table he supplied in January, 1977.

He believed this table would expedite computations for condition write-up sheets and for developing the Guide to Initial Stocking Rate section of the Technical Range Site Descriptions.

He asked that you do not lose sight of how the figures were determined. An explanation is at the end of the table.

#/ac usable @ PGU / AUM/Ac / Ac/AUM
800 / 1 / 1
400 / .5 / 2
266 / .33 / 3
200 / .25 / 4
160 / .20 / 5
133 / .17 / 6
114 / .14 / 7
100 / .13 / 8
89 / .11 / 9
80 / .10 / 10
73 / .09 / 11
67 / .08 / 12
62 / .08 / 13
57 / .07 / 14
53 / .07 / 15
50 / .06 / 16
47 / .06 / 17
44 / 306 / 18
42 / .05 / 19
40 / .05 / 20
38 / .05 / 21
36 / .05 / 22
35 / .04 / 23
33 / .04 / 24
32 / .04 / 25
31 / .04 / 26
30 / .04 / 27
29 / .04 / 28
28 / .03 / 29
27 / .03 / 30
26 / .03 / 31
25 / .03 / 32
24 / .03 / 33
24 / .03 / 34
23 / .03 / 35
22 / .03 / 37
21 / .03 / 38
21 / .03 / 39
20 / .03 / 40
18 / .02 / 45
16 / .02 / 50

How ac/AUM and UAM/ac are determined:

Assume 160 of usable forage acre @P.G.U.

800 (AUM equivalent)  160 = 5 ac/AUM

or

Estimated 6 ac/AUM @ P.G.U.

800  6 = 133 usable #  800 = .17 AUM/ac

Very simply 1  ac/AUM = AUM/ac or 1  AUM/ac = ac/AUM