Applications of ENTS Measurements   Robert Leverett
  Nov 07, 2005 10:42 PST 

   But really, why does it matter? What is at stake if numbers on the
tree lists are off by say an average of 10 feet and a few by 20 or 30?
What if some land manager believes he/she has a 200-foot tuliptree on a
managed property - an proud of it? Do we accomplish anything by
deflating the numbers for a proud custodian? Lives are not at stake.
Careers do not hang in the balance. Well, in terms of the specific list
or property, nothing particularly useful may come from ENTS scrutiny,
and however we proceed, it should be respectful. But the answer to what
is at stake is more illusive. It lies deeper than the impact (or lack
thereof) of a bad number on a champion tree list. We have discussed this
issue before and two public properties best illustrate what is at stake,
namely Mohawk Trail State Forest, MA and Zoar Valley, NY. I'll conclude
by reviewing what was at stake with them.

     Prior to ENTS, these exemplary properties were largely anonymous
and vulnerable to the prevailing managment philosophies for the public
forests of the represented states. But through the ENTS mission,
persistence, and competance, these exemplary properties have become
recognized, at least in widening circles, as ecological treasures within
their respective states. Before, they were just convenient sources of
timber and places to recreate. ENTS clearly saw that Zoar Valley and
Mohawk had higher purposes to serves. And how does that tie into our
measuring mania? Well, there weren't any public officials in MA or NY in
positions of power who recognized the uniqueness of the two properties
along the lines that we in ENTS have subsequently documented. It has
taken the development of a historical perspective and a knowledge of
what is on other properties. Beyond the existence of species, one needs
to know what is rare and what is common, what is worth studying and what
is not. Early on we in ENTS began developing sensitivity to the
exemplary, the unique, as a byproduct of seeking ultra-precision in our
measuring. Several of us developed a burning curiosity about what each
species could reach in the way of physical dimensions and of age. So we
sought answers. Our measuring and research allows us to put a new
property into perspective relative to others in the same state or region
and ultimately for the entire eastern U.S.A with respect to what we
define as species potential. But gaining this perspective on a property
took a special effort. We had to go out and take the measurements
ourselves. The data out there proved to be highly unreliable and could
easily lead one to erroneous conclusions about where a property fit into
the grand scheme of things. Mohawk and Zoar Valley were on no radar
screens. When in their book on stand dynamics Oliver and Larson quoted
as gospel some of the most badly mismeasured trees of all times, I knew
we had a major problem on our hands. They didn't have a clue. It was
time for us to roll up our sleeves and go to work and we've been doing
that ever sense. But it all started from our intense focus on measuring


Robert T. Leverett
Cofounder, Eastern Native Tree Society
Re: Continuing Ed's theme   Edward Frank
  Nov 07, 2005 19:58 PST 


Your second point deals with the value of the accuracy in our measurements.
I like your essay about the value in documenting accurate tree measurements
in the political process of protecting worthwhile sites. As I see it there
are four major points that need to be addressed when talking about ENTS
measurement techniques: 1) Tree measuring guidelines - Will's manuscript is
excellent, but even at that we are constantly trying to clarify and expand
what we are doing, be it trying to tighten definitions, add additional
measurements like Rucker Index and volume calculations, or explore new
applications and concepts like max lateral spread, tree dimension index, and
tree shape plots. 2) Document the error present in other measurement
methods and examine the source of this error. We are doing this with the
Mismeasured tree project and some of these ongoing discussions. 3)
Demonstrate that the ENTS laser techniques are valid. We are doing that
with the listing of trees actually measure by climbing them and taping
them, compared to our laser clinometer measurements. 4) We need to
demonstrate there is some value in obtaining more accurate measurements,
beyond just accuracy for accuracies sake. I discussed this fourth need some
with Lee Frelich at the last Forest Conference. Your discussion in this
post was an excellent example to be included in this demonstration. I would
like to see statements and discussions from our scientific experts that talk
examples of what can be done or demonstrated scientifically with more
accurate measurements, that can not be accomplished with say data from the
American Forest and other Big Tree lists with less reliable data. Perhaps
you could help facilitate this aspect by helping me draw such material from
Lee Frelich, Tom Diggins, Gary Beluzo, Bob Van Pelt, Don Bragg, and others
that may have examples to share.

Ed Frank

What to do with our data?   Edward Frank
  May 26, 2006 14:02 PDT 

Bob Leverett and his colleagues have collected an enormous amount of data relating to the relatively small area of MTSF. Others have collected large amounts of data from other sites around the country.   We have data on a less detailed scale from across the eastern US. It is foolish to think that the only use we can make of the data is to generate Rucker Indexes to facilitate our competitiveness. Bob is trying to interpret the vast reserve of measurements taken at MTSF through the use of multiple iterations of the Rucker Index and other indexes. I must applaud these efforts. He is, I am sure, looking for other ways to make use and interpret this reserve of data. A goal of this organization should not be just to collect the measurements of tall trees, but to find ways to use our measurements and our data sets to better understand the processes taking place in our forests.

I would like to ask each of you to think about this problem, brainstorm and to try and come up with creative, practical, or off-the-wall ideas for and making use of our data sets to better understand the forest and process taking place within the forests. Will Blozan, Bob Leverett, Colby Rucker and others devised the Rucker Index. Bob is using multiple iterations of the Rucker Index in some of his reports. We have talked in the past about Rucker Indexes of other tree measurements, or using different numbers of individuals, and we have used these to some limited extent. Bob is using generic height indexes, girth indexes, and species indexes to look at his information. Will devised the concept of the Tree Dimension Index. Jess Riddle, compiled the first list using TDI and Bob compiled an extensive list of White Pine trees using the TDI. Colby has published tree profiles listing the maximum heights of every tree species measured on a site. We are trying things, but for the most part they are hit and miss. What else can we do? What can we do better? What ideas do any of you have? All of you are literate (or at least can use a computer), some have more education in forestry, some more in math, others more practical experience in the field. Each of you have different backgrounds and perspectives to bring to bear on the problem. What should we be doing with our data?

Ed Frank
RE: What to do with our data?   Robert Leverett
  May 30, 2006 09:07 PDT 

   One of the early objectives of Rucker indexing was to eventually be
able to determine the maximum growth potential for eastern species both
range wide and regionally. A spinoff of this kind of investigation is
the development of predicative models using independent variables
associated with climate, geology, topographical features, and age.
Gathering good GPS location data can help immensely in tying down
climate and geology and general topography. In the past, Gary Beluzo has
proposed methods for computing a micro-topography index. A logical
extension of what we are presently doing with Rucker indexing is to get
serious about collecting data on these other variables. However, age is
a bit of a challenge unless you own an increment borer and we often do
not want to core the objects of our affection. Age dating by eye,
meaning evaluating physical characteristics, has value, but requires a
lot of experience. It works much better for some species than others.
Nonetheless, we could get serious about collecting more data on each
tree than most of us presently do. If the data are there, I'm sure the
PhDs in ENTS will figure out what to do with it. However, settling on a
data collection protocol is sticky. If some data elements prove too
difficult or time consuming to gather, it is easy to get frustrated and
dump the protocol. There is a tendency to over-design. However, we
should still discuss adopting a standard measuring protocol for an
ENTS-wide database and come to some agreement on the format and

   There is an area of research that we could take a long way and that
is tree form analysis. It fits with the volume modeling that some of us
are doing. It is a statistical way of describing the proportions of a
species such as a width to height ratio (or the inverse) for in-forest
and open-grown forms. Species like hickories differ greatly from the
oaks. There is a role for quantification.

   Well, these simple ideas are to get the ball rolling.

RE: Multiple Iterations of the Rucker Index   Roman Dial
  Jun 02, 2006 23:19 PDT 

The recent discussions on the Iterated Rucker prompted me to try and
visualize what was being measured. Thanks to all of you for this,
although it seems pretty painful for many ENTS to revisit the topic!

Generally I like to visualize not just the *mean* of the tallest
specimens of the ten tallest species, but also the tallest specimens of
the ten tallest species lined up from tallest to tenth tallest, like
kids in a big family. In some sense this is a 2 dimensional bar graph
with horizontal axis representing the rank order among species and a
vertical axis as height. Now I guess the Rucker Index is the horizontal
line marking the mean of these heights.

What I would like to see is the data representation for the 10th
Iterrated Rucker of a site (i.e. 100 trees?) as a 3D graph. It would
have the same height and among-species rank order axes as used for the
visualization of the Rucker Index data, with an additional
within-species rank order axis as well, giving the heights of the ten
tallest individuals of each species. Now I think that this is not
strictly the data of the iterrated Rucker, but perhaps a subset, since
it might (maybe often?) happen that some 11th species shows up in the
2nd (or greater) Iterated Rucker as one of the top ten trees but isn't
among the top ten.

I guess that what I would expect of a "uniform, homogeneous, and smooth"
forest would be a gently tilted plane brushing the tops of these 100
trees arrayed from tallest to shortest in two directions. On the other
hand a very heterogeneous site might be convoluted and not planar at
all, maybe even rumpled. And a crude idea of the Iterated Rucker is the
series of horizontal lines that cut through the tops of the trees
parallel to the among-species axis.

If someone has these data -- the ten tallest specimens of the ten
tallest species at a given site -- I'd like to make (or see) a 3D bar
graph. I understand that these are not exactly the data used for
Iterated Ruckers (perhaps a subset), since it might (maybe often?)
happen that some 11th species shows up in the 2nd Iterated Rucker as one
of the top ten trees in the second rankings.

I also wonder if what we are usually doing with these indices is to try
and capture some of the beauty as well as a quantitative descriptor of
the forests. Has anyone tried making graphs like these already?

Roman Dial
RE: Multiple Iterations of the Rucker Index WAY COOL   Will Blozan
  Jun 03, 2006 09:25 PDT 


That is an interesting idea. I will plot some Smokies (heavily sampled!)
trees when I get some time.

Re: Multiple Iterations of the Rucker Index   Edward Frank
  Jun 03, 2006 18:52 PDT 


It strikes me that this idea is something completely different from the
entire question of multiple iterations of the Rucker Index. It seems like a
worthwhile approach to pursue. As for data sets capable of performing this
function we actually have several. There is enough data from the Great
Smoky Mountains National Park, Mohawk Trail State Forest, and possibly from
Cook Forest. In any case data could be combined from several areas to create
graphs from broader regions.

I don't think that the numbers used in the proposed grid of ten trees from
ten species is necessarily critical. The graph could be expanded to include
more species than ten, or more examples from each species. There needs to
be some minimum number of data points to make the analysis worthwhile, but
the methodology could be applied to sites with less species or less examples
as well. As a graphical display it does not rely on a specific number of
samples processed in a particular way in order to generate a numerical value
that can be compared between sites, so comparisons between sites with
differing amounts of detail could be made.

This is more like a 3-dimensional tree profile graph.

Ed Frank

Re: Multiple Iterations of the Rucker Index WAY COOL   Don Bertolette
  Jun 03, 2006 21:18 PDT 

While like many, I can get lost in the math of it all, graphs work for me,
and as I followed along with Roman's description of the 3D graphs, and the
"rumpled" heterogeneous "canopy", I couldn't help but think of aerial
photography and textural qualities of heterogeneous forest
structures/emergent were dang near poetic Roman!
RE: Multiple Iterations of the Rucker Index WAY COOL   Roman Dial
  Jun 04, 2006 14:09 PDT 

Thanks WIll, Ed, and Don.

Happy that you guys like the idea and hoping that we can see a
representation of a few sites that also have Iterrated Ruckers so we can
get a feel for those sequences.

Looking forward to seeing the graph -- although it being summer and all
I am not expecting anyone to throw it together soon!

RE: Multiple Iterations of the Rucker Index   Robert Leverett
  Jun 05, 2006 05:14 PDT 


   Do I have data? Do I have data? You betcha! Presently, John Eichholz
and I have enough data from MTSF to do 41 iterations of the Rucker
index. Some species aren't sampled well enough, but we have the data.
This is the normal RHI we've been discussing. RHI allows for the order
of species to be shuffled, i.e. the same species are not necessarily
repeated from iteration to iteration. You say the word and I'll ship you
the data.