Within-site variation in counts (vari- ance, log scale) 0.04
Rate of change of inter-observer mean (log scale) 0.05
Assuming that the prices paid for F2 and F3 yellow poplar logs were $150/MBF and $140/MBF in Doyle log scale, the purchase prices for red oak logs were $300/MBF for F2 grade and $280/MBF for F3 grade, and the average operating cost ranged from $160/MBF for circular sawmills to $200/MBF for band sawmills, a value ratio was computed based on species, diameter classes, and sawmills (Fig.
of thousand bd ft of Species (in.) logs lumber tally ($/MBF) Red oak 10 22 485 11 16 422 12 30 420 13 26 446 14 27 454 15 29 469 Yellow poplar 10 7 341 11 9 304 12 20 301 13 18 334 14 12 326 15 14 357 Dollars per Dollars per hundred cu ft of thousand bd ft of Species net log scale ($/CCF) net log scale ($/MBFLS) Red oak 320 782 264 639 267 620 286 584 291 607 304 557 Yellow poplar 240 518 206 452 205 442 228 474 225 421 254 467 (a) SED = small-end diameter (inside bark); bd ft = board feet; cu ft = cubic feet.
To calculate LO, the volume of lumber produced (expressed in board feet lumber tally) in excess of the Scribner log scale volume processed was divided by the Scribner volume of logs and expressed as a percentage.
Measures of the volume of lumber produced per unit of log input can be influenced by a range of factors in addition to log scale. These factors include technology, log size, lumber size, lumber grade, and market conditions for lumber and residue--particularly coarse residue.
For each study sample log, absolute sweep, small-end diameter, and log length were used to determine sweep log scale
Assuming that the average log size at this sawmill is 100 BF (International 1/4inch log scale
) and using the overrun statistics presented in Figure 4, then approximately 106 BF of lumber (1.058 x 100 BF) would be recovered from one highly elliptical log in comparison to the estimated 117 BF (1.169 x 100 BF) of lumber yielded from one low-ellipticity shaped log.
For hardwood logs with average sweep of 3.3 inches and greater (12-foot log length basis), and log scale
deduction of over 15 percent, lumber yield can be 10 to 12 percent higher when curve sawing.
Forty-eight percent of log scale
volume (scaling yield) was converted into clear dimension parts.
Figure 1 plots the amplitudes of ERGs recorded from dark-adapted Tachypleus and Limulus eyes on log scales
as a function of log light intensity.
Spelter (2004) and Fonseca (2005) provide additional information and references about Scribner and other log scales