Basal Area Per Acre

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Basal Area Per Acre
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Basal Area Per Acre at One Point
BAF Square feet of basal area per acre for each
IN tree regardless of tree DBH or
height Example Four trees in with a BAF 10 at
one point 4 trees IN x 10 sq ft/ac 40 sq
ft/ac Could be 4 1 inch DBH trees, 4 10 inch
DBH trees 4 50 inch DBH trees Still 40 sq ft of
basal area per acre
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Basal Area Per Acre with Many Points
Average over the points 15 trees IN from 4
points, BAF 10 BA/ac 10 x (15 / 4) 37.5 sq
ft /ac General formula BA/ac
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Basal Area Per Acre with Many PointsExamples
In the first example there are 8 trees per plot x
BAF 10
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Basal Area Per Acre with Many PointsExamples
Basal area can be calculated by combining the
points, then averaging Or Point by point, then
average
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Basal Area Per Acre by Tree Class
Every tree IN counts one BAF of basal area per
acre. Any other division is your choice. At one
BAF 20 point, 3 hardwood and 4 pine IN Hardwood
BA/Ac 60 sq ft/ac Pine BA/AC 80 sq
ft/ac Total BA/Ac 140 sq ft/ac Tree class
BA/Ac
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Basal Area Per Acre with Many PointsExamples
See the example tally Table 4 and 5 on pages 19
and 20 in the text. Three points, BAF 10, tally
by DBH and Logs 10 inch DBH, 1 log ? 5 trees
16.67 sq ft/ac 10 inch DBH, 1½ log ? 2 trees
6.67 sq ft/ac 10 inch DBH, all heights ? 7
trees 23.3 sq ft/ac Basal area can be calculated
for any division of the trees
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Basal Area Per Acre with Many PointsExamples
1 log trees ? 8 trees 26.7 sq ft/ac 1½ log
trees ? 8 trees 26.7 sq ft/ac 2 log trees ?
5 trees 16.7 sq ft/ac 12 inch DBH, any
height ? 14 trees 46.7 sq ft/ac 14 inch DBH,
any height ? 7 trees 23.3 sq ft/ac All trees ?
21 trees 70 sq ft/ac No matter what categories
or classes, the total across the classes has to
be 70 sq ft/ac.