Volume Calculations Valuing trees

Volume Calculations / Valuing trees

Sept 26, 2008

Hey Bob, I know next to nothing about the sophisticated methods ENTS
people use to determine tree volumes- I only know standard, basic,
simple methods of tree measurements used by field foresters. But, I
should think that there must be some way using the best technology in
the world today to get an exact 3 dimensional image of any tree- using
something like radar or some other electromagnetic radiation- by
moving the energy generator AROUND the tree- sort of like a giant scan
of a hospital patient.

The scan could scan the shape to great detail in 3-D, then incorporate
that into data into a holograph in order to project it- and I'm sure
mathematical geniuses could easily then use that data to calculate the
volume of the tree to an order of accuracy orders of magnitude beyond
current ENTS methods.

And, while at it, why not use penetrating energies such as the
hospital scan to give a true internal image of the tree which could
then be studied for whatever reasons, such as the work done by Alex
Shigo to determine the course of "discoloration and decay"- or to
discern the value of the tree for wildlife habitat (assuming some
hollows in the tree).

And, if this is done for many trees close together- it could be useful
to Gary Beluzo who I recall is interested in the emergent properties
existing in forests- and for that, having such information and
modeling tools- might be significant in such research.

Just a crazy thought. <G>

Joe Zorzin

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TOPIC: Sneak preview
http://groups.google.com/group/entstrees/browse_thread/thread/826c8f9efe163151?hl=en
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== 1 of 2 ==
Date: Fri, Sep 26 2008 2:37 pm
From: dbhguru@comcast.net

Joe,

I have no doubt that methods such as those you suggest could be developed, and perhaps some are as we speak. However, their widespread field employment would require a source of money that I currently don't have the slightest access to. But for our contribution, maybe if we continue to beat the drum long enough, university researchers with the financial wherewithall will take notice and become interested. You'd think that state forestry departments would be interested, but so far that hasn't happened in the Northeast. I'm not entirely sure about the Pacific Northwest, but do believe that BVP has a pretty good working relationship with state of Washington folks.
I see lots of ENTS work as up-front development in nature. I often think of us as the low cost vanguard to what may be extensive research later. The most practical application of our volume and individual dimensional analysis is likely to be the establishment of time-based growth curves, that express the natural capabilites of a number of species. The curves could act as baselines to provide managers with a better understanding of how the species they select to manage would behave over time if left unmanaged. I do realize that this information is supposed to be out there, but in truth I see little evidence that very many forest managers truely grasp what a specific site can be expected to produce over a time span of 150 years. I would not argue with their short-term undertsanding, but I think most of them have lost sight of the longer growth cycles, if they actually ever had an understanding. I could give dozens of examples, but am not making the point to criticize the people out there now. You and a few others like Russ Richardson seem to have a good appreciation for what is possible, but over all, it appears to be a diminishing talent. The breadth of vision seems to be shrinking proportional to the shrinking of the average size of the species and processing equipment.
If we continue to gather data, the ENTS databases will eventually allow the likes of Drs. Lee Frelich, Don Bragg, Tom Diggins, and perhaps a few others to establish statistically validated maximum growth-volume curves for a wide range of latitudes, longitudes, altitudes, and average levels of precipitation. For the present, that is where we're headed, but I think I'd like to pursue research in the direction you suggest with a couple of university contacts.

Bob

== 2 of 2 ==
Date: Fri, Sep 26 2008 3:24 pm
From: the Forestmeister

Sounds good- and you're right, there's little if any such info-data-
models of the growth of trees into real biological maturity, not the
phony, poorly thought out "financial maturity" which is a small
percentage of the full life span for most species. Any current
suggestion that trees ought to be left to grow to great size/age-
either in reserves or for economic value can't be convincing until we
have solid scientific research.

As I've suggested in the past, it's time for all of us to come up with
real numbers for all the "intangible values" of trees and forests.
Thus, even for trees/forests which when timber values peak out- the
other values are still growing, maybe even faster. Without coming up
with a value system for all the values, the battle is lost.

The discussion on the creation of those non market values must
commence.

Joe

== 2 of 6 ==
Date: Sat, Sep 27 2008 1:09 pm
From: the Forestmeister

Well, I don't know what the accuracy of current methods are when
estimating tree volumes but it's not likely to be more than plus or
minus 10% if you're including all the crown. With a digitilized scan
done by my the technique I'm fantasizing about - I should think it
would be accurate to plus or minus a tenth of a percent which would be
orders of magnitude better.

Regardless of that issue- I think it's urgent for us to start putting
real dollar signs on all the currently intangible values- which are
more likely to be significant for large trees- the larger the trees,
the greater for those intangible values. Though there may not yet be
market values for these considerations- if we pretend that there are-
maybe they'll happen.

For example, let's say we do come up with a value system- then say,
the state wants to buy a property to add to an existing state forest/
park- when they negotiate with the owner they should have to factor in
such values- because we'll all demand it. After all, when people
appraise something like antiques- there is no logic to it other than
supply and demand. If a landowner were told that the value of their
property was something beyond what some real estate appraisser says-
then it will be so if they believe it. Much of our economic system is
"faith based", not logical- so we must all have faith in the true
values of large trees and old growth forests, c'est nes pas?

Joe

== 3 of 6 ==
Date: Sat, Sep 27 2008 1:19 pm
From: the Forestmeister

BTW, a suggestion- to check how accurate current methods are for
measuring the volume of large trees- I suggest going to a forest that
is about to be logged- no doubt you can find some really big trees-
then measure them- then when that tree is cut, it should be easy to
gather all the crown, in pieces and measure the volume of them by
placing in a tank filled with water (specially designed of course)
whereupon the displacement of the water would give an accuratge
measurement- and the cut logs could easily be measured extremely
accurately before haulded off to the mill. The actual physical measure
by this method should be extremely accurate- then compare that to
various methods now being considered (of which I know nothing other
than rough measurements for merchantable logs).

Joe

== 4 of 6 ==
Date: Sat, Sep 27 2008 3:34 pm
From: ForestRuss@aol.com

Joe:

I strongly agree with your premise for valuing trees, especially large old
ones and the land and sites they occupy and I applaud your thoughts. I'd like
to hear more before I throw my two cents worth in but I think you are onto
something..especially with the increasingly documented value of older growth
forests for carbon sequestration.

Russ

== 5 of 6 ==
Date: Sat, Sep 27 2008 4:35 pm
From: dbhguru@comcast.net

Joe,

The water displacement process can be used in a piecemeal way to test the closeness of different formulas. Over the years, I've discussed water displacement as the litmus test of volume in emails. The big question for the analyst to ANSWER is how far does the volume of a log or section of trunk or limb differ from the frustum volumes of the more common regular geometrical solids. The frustum formula:

V = Pi*F*H*[a^2 + b^2+ a*b]

where F = (1/4) for a neiloid, (1/3) for a cone, and (1/2) for a paraboloid and a and b are the radii at the ends of the frustum is the one we apply most commonly these days. The formula assumes a cross-sectional area that is circular. However, the formula can be modified if the cross-sectional shape is more elliptical. In this case we would need to use the semi-major and minor axis from each end of the frustum. The formula would look like the following:

V = Pi*F*H*[a1*b1 + a2*b2+ SQRT(a1*a2*b1*b2)]

The utility of these formulas is their repeated application. We break long lengths into series of short sections. In the aboev formulas, H should not be high or too many changes in trunk shaape can be obscured.
In trees that Will Blozan has climbed and modeled (he's done by far the most in the eastern United States), his frustum height are often a meter. He climbs the trees to get girth measurements ever meter of height. In addition, he frame maps trunk splits by using a highly accurate method we developed in ENTS to determine cross-sectional area. We don't just assume circularity or ellipticality where that is obviously not the case.
Before leaving the subject I note that log volume charts commonly employed by foresters are of no value to us. They may too many simplifying assumptions. I started out with them years ago, and while they may work for large numbers of logs, I found them to miss individual trees, especially large, old ones. So from that point one Will and I went it alone.
All this will be covered in the book on Dendromorphometry that Drs. Frelich and Bragg and Will Blozan and myself plan to write. It is supposed to be under way at this point, I because of my medical situation, I needed time off before taking the plunge. However, when the book is eventually completed, it will include many methods for volume modeling - on a poor man's budget. That will leave plenty of room for high tech wizardry in the future, some of which is already being developed and employed by the likes of Drs. Steve Sillett and Robert Van Pelt in Washington.

Bob

== 6 of 6 ==
Date: Sat, Sep 27 2008 4:38 pm
From: dbhguru@comcast.net

Russ and Joe,

I think everyone on this list agrees in principle. However, the thought processes to address all the ecological, climitalogical, social values, etc. are daunting. I must confess that I can't quite figure where to begin. Ed Frank has a good mind for tackling some of the up front thinking on the subject. There may be efforts already underway. Lee Frelich may know of some.

Bob

== 2 of 5 ==
Date: Sun, Sep 28 2008 4:49 pm
From: doncbragg@netscape.net

Bob/Joe--

The water displacement technique for measuring log volume has already been described in research papers--one such paper was recently published in the Southern Journal of Applied Forestry. You can find the abstract of this article at: http://saf.publisher.ingentaconnect.com/search/article?title=volume+measurement&title_type=tka&year_from=1998&year_to=2008&database=1&pageSize=20&index=4 (unfortunately, you need a subscription to get the full article). The unique aspect of this work is that the author took detailed measurements of logs and then translated them so that a computer-controlled system (often used to create miniaturized plastic models) made small versions of the logs to displace, so the large bole wouldn't have to be put into an Olympic-sized swimming pool to displace the water.

Definitely a technique to highlight in the Dendromorphometry book...

Don

~~~~~~~~~~~~~~~~~~~~~~~~~~~
Don C. Bragg, Ph.D.
Research Forester
USDA Forest Service
Southern Research Station
DonCBragg@netscape.net
~~~~~~~~~~~~~~~~~~~~~~~~~~~

The opinions expressed in this message are my own, and not necessarily those of the Southern Research Station, the Forest Service, or the USDA.

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