The Truth ISN'T Out There

KMorrisD kmorrisd at aol.com
Wed Aug 26 21:22:05 EST 1998


Mike Hagen <mhagen at olympus.net> wrote:

>So how can you forecast grade improvement when it's not just based on
>diameter? Statistical ranges?  Has anyone worked with Jim Arney's
>program?

INFORM and WINYIELD allow you to enter probability factors (as percentages) for
each species and grade to increase to the next grade.  The hard part is
figuring out what those probabilities are.  There are research papers on this
for the Northeast.  I don't know about other regions.

The problem with the research papers is they're for unmanaged stands. 
Probabilities would be much higher with well-managed stands, particularly those
that have been under management for some time.  

I have a draft paper that calculates grade value increase rates for
northeastern timber species.  Grade value increase rates tend to average about
the same as volume increase rates, but some species make big jumps at certain
diameter threshholds. The paper has lots of references for this region.  Let me
know if you'd like a copy.

What is Jim Arney's program?

>By the way Karl, I see you'll be presenting at the Science of Managing
>Forests To Sustain Water Resources conference in Sturbridge.
>Congratulations and I wish it wasn't so far away, or I'd attend. 

Thanks Mike.   Reminds me I need to get to work on that paper. <:-{>  It should
be an interesting conference, and it looks like the weather might make it even
more interesting.  The managers at the Quabbin Watershed have been doing a lot
of thinking and work on `weather-proofing` the forest there.

KMD





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