====== Pole Specifications (Southern Pine) ======
Minimum diameter at breast height (outside bark)<sup>1</sup> of trees to meet
American National Standard specification for various classes of southern 
pine poles.

^Pole Length (Feet)  ^Dist. Butt to ground line   ^Pole Class                  ^^^^^^|
^:::                 ^:::                         ^1   ^2   ^3   ^4   ^5   ^6   ^7   |
^:::                 ^:::                         ^Minimum Top Circum. (In.)   ^^^^^^|
^:::                 ^:::                         ^27  ^25  ^23  ^21  ^19  ^17  ^15  |
^:::                 ^:::                         ^Minimum Top Diameter (In.)  ^^^^^^|
^:::                 ^:::                         ^8.6 ^8.0 ^7.3 ^6.7 ^6.0 ^5.4 ^4.8 |
^:::                 ^Feet                        ^Inches (Dbh-ob)             ^^^^^^|
|20                  |4                           |11.2|10.5|9.8 |9.0 |8.3 |7.6 |7.0 |
|25                  |5                           |12.1|11.4|10.7|9.9 |9.2 |8.3 |7.8 |
|30                  |5 1/2                       |13.2|12.3|11.6|10.7|9.9 |9.0 |8.5 |
|35                  |6                           |14.1|13.2|12.3|11.4|10.5|9.8 |9.0 |
|40                  |6                           |14.8|13.9|13.0|12.1|11.2|10.3|9.6 |
|45                  |6 1/2                       |15.6|14.6|13.6|12.7|11.8|10.9|10.1|
|50                  |7                           |16.3|15.2|14.1|13.2|12.3|11.4|10.5|
|55                  |7 1/2                       |16.8|15.7|14.6|13.7|12.7|11.8|--  |
|60                  |8                           |17.4|16.3|15.2|14.1|13.0|12.1|--  |
|65                  |8 1/2                       |17.9|16.6|15.6|14.6|13.6|--  |--  |
|70                  |9                           |18.4|17.4|16.3|15.0|13.9|--  |--  |
|75                  |9 1/2                       |19.0|17.7|16.6|15.6|--  |--  |--  |
|80                  |10                          |19.5|18.3|17.0|15.9|--  |--  |--  |
|85                  |10 1/2                      |19.9|18.6|17.4|--  |--  |--  |--  |
|90                  |11                          |20.3|19.2|17.7|--  |--  |--  |--  |
|95                  |11                          |20.6|19.5|18.1|--  |--  |--  |--  |

<sup>1</sup> D.B.H = Minimum Circumference 6' from butt/(.88 X 3.1416)

Source: Hawes, E. T. 1947. A method of determining southern pine pole classes from d.b.h. Jour. 
Forestry 45: 204,205 illus.