Algorithms: Forest Service Equations for Down Logs/Snags in Summary Program

Where NTPA = Number of logs per Acre



Where

DL = Diameter Large End (DBHI*0.1)
DS = DL - [(0.125 inches per foot)*(L feet)]
L = Log Length for down logs (PRHT)
#logs/acre = (NTPA*0.01)


Log Wieght/acre (in Tons)



Where Adj Dens is adjusted density faCtor for species
DENSITY = New Object() {30, 30, 0, 0, 28, 25, 0, 0, 0, 0, 28, 28, 25, 27, 28, 0, 0, 0, 28, 0, 28, 28, 28, 28, 28, 28, 28, 30, 29, 29, 27, 27, 25, 28, 27, 0, 27, 0, 27, 0, 28, 29, 0, 0, 30, 28, 29, 29, 0, 0, 25, 25, 25, 25, 0, 0, 30, 30, 30, 0, 29, 29, 29, 29, 29, 29, 0, 28, 0, 33, 28, 42, 26, 28, 24, 33, 42, 24, 35, 35, 35, 35, 35, 35, 35, 35, 35, 30, 30, 0, 0, 28, 25, 0, 0, 0, 0, 28, 28, 25, 27, 28, 0, 28, 28, 28, 0, 28, 28, 28, 28, 28, 28, 28, 30, 29, 29, 27, 27, 25, 28, 27, 0, 27, 27, 27, 0, 28, 29, 0, 0, 30, 28, 29, 29, 0, 0, 25, 25, 25, 25, 0, 0, 30, 30, 30, 0, 29, 29, 29, 29, 29, 29, 0, 28, 0, 33, 28, 42, 26, 28, 24, 33, 42, 24, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 24, 40, 35, 28, 35, 40, 40, 35, 40, 35, 0}

Decay Factor is decay class factor for log
Decay Class Decay factor
1 1.00
2 0.85
3 0.70
4 0.55
5 0.44


Volume per Acre in Cubic Feet (Down logs and snags only)



Where
DL = Diameter Large End (DBHI*0.1)
DL = [DBHI*0.1 + (0.125 inches/ft)*4.5ft] for snags
DS = DL - [(0.125 inches per foot)*(L feet)]
L = Log Length or height for down snags (PRHT)
NT/A = #logs/acre = (NTPA*0.01)