explanation of log rules

[brdmkr]

I have been lurking around in the tool box  :P :P and I found the log rules.  I have heard of these, but I really don't understand them.  First, why do the different rules provide different estimates of bdft for the same log ??? ?  Second, do these numbers represent what your actual yield should be from a log?  Third, do most of you yield close to these figures or what percentage of the estimate to you consider acceptable ??? ??? ?

Thanks for filling me in!

[beenthere]

There are 'lots' of answers to your good questions.
One source, I'd recommend taking a look at, is called "A Collection of Log Rules" and it can be found at this location.

Log Rules

[ARKANSAWYER]

   Doyle is a older rule and most are close on scale on logs over 18 inches.  The differerance is mostly because they did not want logs under 18 inches so they made them pay less so people would  not bring them in.
  Doyle says a 12" 8' log has 32 bdft in it but you can saw out some boards and  a 7x9 tie which has 42 bdft.
  International 1/4 scale says it has 45 bdft.   I can saw out 50 to 60 bdft most of the time.   But I would rather saw 18 inch logs.
  Here it is mostly hardwoods and we use the Doyle scale because of the grades and price differance for lumber.  We do not want little oak trees so we pay so little that it is not worth the time to log them.  Let them grow.  But now pulp wood is taking them by the truck loads so they are getting cut.

[Frank_Pender]

Out here on the Left Coast we have the primary scale called Scribner that is used for our softwood timber.   Some of use use the same scale for hardwoods, as well.  Different areas use some different scaling bureaus such as the Columbia River and the Yamhill bureaus.  Each area seems to have its favorite system.  My opinion is that the big boys control the systems and therefore are designed these days to favor them and their methods of buying and selling lumber produced from the logs they purchase or harvest from their lands.

Here in Oregon we have a severence tax that is spread around to different government agencys such as county roads and the public school system.