Table of Contents

Volume Per Sq. Ft. of B.A. (Int. 1/4 and Standard Cords)

Int. 1/4 Inch

(Prism BAF-10) Form Class 79
Ave. Number Logs per Average Tree
DBH 1 1 1/2 2 2 1/2 3 3 1/2 4
8 57 77 92 109 – – –
9 63 84 102 115 124 – –
10 70 92 112 126 141 – –
11 73 95 118 135 151 – –
12 74 98 122 140 158 168 179
13 76 102 127 146 166 178 191
14 77 103 129 150 170 183 197
15 77 104 130 152 174 190 205
16 78 104 131 153 176 193 209
17 79 106 134 160 181 198 217
18 79 107 136 160 184 201 220

This table may be used for rough estimates of sawtimber volume per acre (Int. 1/4“ Rule) without making log count per point. 

(1) Find BA at sample point
(2) Multiply BA by factor for average size tree 
    (DBH by log length)

Pulpwood Volume per Square Foot B.A. (Standard Cords)

(Prism BAF-10)
Ave. Number 5-foot Bolts Per Average Tree
DBH 1 2 3 4 5 6 7 8 9 10 11 12
4 .06 .09 .13 – – – – – – – – –
5 .07 .10 .13 .17 .20 – – – – – – –
6 – .10 .13 .17 .20 .23 .26 .29 – – – –
7 – – .13 .16 .19 .23 .26 .29 .32 – – –
8 – – .13 .16 .19 .22 .25 .28 .31 .35 .38 .41
9 – – – .16 .19 .22 .25 .28 .31 .34 .37 .40
10 – – – .16 .19 .22 .25 .28 .31 .35 .37 .40
11 – – – .15 .19 .21 .25 .28 .31 .34 .37 .40
12 – – – .15 .18 .21 .24 .28 .31 .34 .37 .40
13 – – – .14 .17 .20 .23 .25 .28 .31 .34 .37
14 – – – .15 .18 .21 .24 .27 .30 .34 .37 .40
15 – – – – – – .24 .27 .30 .34 .37 .40

Vol./Acre = Sum Basal Area/point X Factor
No. of Points