Measuring multi-trunked individuals   Edward Frank
  Nov 25, 2004
This discussion began with the publication of a measurement of a multi-trunked Corylus made by Scott Wade.  I am going to start with a later post in the series in which I framed the argument for discussion first, then jump back to the beginning of the discussion 

Ed Frank

Re: Different Rules for measuring   Edward Frank
  Nov 25, 2004 09:24 PST 
Bob, Scott, Paul, and other ENTS

I focused on this issue for several reason. I tend to agree with the one
stem-one individual model, however since my first discussions with Colby
and others even before I joined ENTS at the back of my mind was the
question of how we should deal with mulit-trunked trees. Clearly it does
not affect the height of the tree, because the highest point is always on
one trunk, but it does affect measurements of girth and crown spread.

Looking at what we measure, we have found a number of what normally would
be considered shrubs reaching tree height. Most standard trees have a
single trunk, with occasional doubles. Doubles are those that are fused at
the base, and that fusion may persist for a distance up the trunk before
separating at height. I have no problem considering these as separate
individuals even thought they may be genetically identical and may be grown
from the the same root mass. This is because the normal habit of these
species is to have a single stem. (at the back of my mind is a voice saying
don't doubles deserve some love too?)

Other species, like some of the willows, and some of the shrubs we measure
have a a normal habit of forming multiple stems. The question that bothers
me is whether or not we are treating these naturally multi-trunked
individuals equitably and fairly by considering only the largest of their
multiple stems? I don't think we are. Trees should be taken for what they
are rather than forcing them and our measurements of them to conform to an unnatural standard.

Then comes the problem of how to measure these multi-trunked or
multi-stemmed individuals. As Paul correctly points out there exits
essentially entire forests of clones of an individual trees. The example
Paul used were acres of aspen clones grown from root sprouts. I don't
think anyone is proposing that we treat this forest of clones as a single
individual for girth and crown spread calculations. It might qualify as an
individual in other considerations.

It is important in my mind that as ENTS members measure trees, we define
our terms and methodologies in a consistent and objective manner. How
should we measure these multi-trunked species or even double-trunked
standard trees? Do our methodologies adequately characterize the form of
the tree (or shrub)? If not how can we do it better? What should the
boundaries be of what is considered an individual? At a minimum we should
count the number of stems in the multi-trunked tree or shrub, however we
decide to define the individual organism.

Even if a consensus is not reached on the issue, the discussion will help
illuminate the options and factors that need to be considered.

Ed Frank
Pennsbury Manor, PA   Scott Wade
  Nov 23, 2004 17:00 PST 

hello all.
Had a disappointing visit to Pennsbury manor today, home of William
Penn, well I guess not too disappointing. I thought there would be some
big trees on a property as old as that, but no. Found a co-champion
Persimmon and a champion Corylus. Can't say I ever saw a Corylus that
could be considered a tree. Measured a thick, but short Sassafras too. I
then visited the retired National champion Catalpa bignoniodes in
Newtown Pa. Wow what a huge tree!, but de-throned for now.
Measurements are below.

Persimmon 74' tall 86"CBH 51' average speard. said to be a seedless
variety that can be eaten without frost to the fruit. I found that
interesting. Co champ for Pa.

Corylus    25' tall 15"CBH 41' avg spread champ for Pa.

Sassafras 65' tall 123"CBH 41' avg spread. Not huge, but I don't
think the registered champion from 93' is still there. The other champ
from Wayne Pa is definitely gone. If anyone has a bigger one, let me
know the numbers and location.

The Catalpa weighed in at 71' tall 271" CBH and 75' avg sprd.

I also received my laser range finder in the mail today! Bushnell
Yardage pro trophy. I am ready to get serious.

RE: Pennsbury Manor, PA   Will Blozan
  Nov 24, 2004 03:57 PST 

Way to go Scott! I am so glad the laser will be entering your hunting gear.
Was the Corylus spread originating from the single stem? That is super wide!
One of my national champion Lindera's has a spread of around 40' in one
direction due to a "snaking" limb that winds through the understory in
search of more light.  ...

RE:  Pennsbury Manor, PA
  Nov 24, 2004 05:43 PST 

The corylus was multi-trunked, about a dozen or so. I measured the largest stem at dbh. then the height and spread of the entire shrub/tree. I really expected to find some older trees due to the age of the property, but apparently it was all run down, and then redone in the 40's.

RE: CORYLUS   Will Blozan
  Nov 24, 2004 08:22 PST 

For our ENTS lists, we measure the portions of the tree that belong to the
stem being measured. One of my TN state record basswood nominees would have
a spread of about 200 feet if I measured both huge stems that originate from
the same base! Same with the three National Champion hazel alders in
Asheville. As a clump, they would spread 60'+, but I measured each of the
three co-champions separately from the same base. Separating the crowns can
be a pain, but it serves to highlight the accomplishments of a single tree,
which is ultimately, our goal.


RE: Corylus
  Nov 24, 2004 17:58 PST 

I respectfully disagree. The Corylus, even though it is multi-trunked, is genetically the same plant. I consider the spread to be of the one plant. It just branches underground, instead of above. When I measure a Magnolia that branches below 4.5 BH, I measure the largest trunk for CBH, but include the height and spread of the entire plant. We have a large weeping beech nearby that has nine trunks. It was planted in the 1700's, and is documented. When we measure it, we include the largest trunk for CBH, and the entire plant for height and spread. Even though it is "multi-trunked" at this point.   I guarantee that if you were able to go back in time, the Cat Island Baldcypress would of looked like two trees until it grew together, but DNA testing has confirmed it as one tree. I will follow the guidelines set forth by ENTS for the purpose of measuring trees for you guys, but the Pennsylvania Forestry Assoc. has different definitions. I am not looking to change your definitions, but relay the definitions given to me by PFA. submitted respectfully,   


Have a nice holiday, and drive safely!

RE: Corylus, measuring multi-trunked "individuals"   Paul Jost
  Nov 24, 2004 18:11 PST  
Wow, if you use genetics as the test for a single tree, then I have
several acres of genetically identical aspen clones from root sprouts
for you to try to measure as one tree!!! It seems deceptive to measure
the diameter of one stem and then list it with the spread of different
stems. If the stems are fused at the ground, then shouldn't you measure
girth at the smallest point at which they are all fused and then specify
that the height is different from bh? That way, the spread and girth
are both for the same biological material. If they aren't fused
together, then how can you treat them as one tree? I understand that
you need to follow the rules that are established for you, but don't you
see any reasons why the rules could be questioned by some of us???

Paul Jost

RE: Corylus, measuring multi-trunked "individuals"
  Nov 24, 2004 19:11 PST 

I realize that some beech and black locust, and apparently alder, can be genetically the same plant for many square miles, but when I look at a small tree, with the majority of the stems originating from a central location, I can't help but consider it "A" plant/individual. I would not consider a root sucker a few feet away from the axis as the same plant when measuring (although it is.) I again state that I will follow the ENTS guidelines when measuring for this group, but I am simply stating a personal opinion, and the opinion of PFA. It will always be up for argument, but maybe that is why spread doesn't account for much in the points system. The difference in points from a 40 ft spread to a 20 ft spread is only five points. The reason I declared it a champ is that there isn't a corylus listed in the 93 edition of Big Trees of Pa. The way the rules are stated, if a tree branches below 4.5', then you measure the largest stem. That is what I did.

RE: Corylus, measuring multi-trunked "individuals"   Paul Jost
  Nov 24, 2004 19:27 PST 

I apologize if I seemed overly critical. It's just a pet peeve of mine
when it comes to coppices and multi-trunked trees. It gets even tougher
with smaller trees/big shrubs. I really do understand that we must
follow rules when measuring to a standard. At times, I just don't like
the standards! I hope that you didn't take it personally....


Measuring multi-trunked individuals   Edward Frank
  Nov 24, 2004 19:52 PST 

Paul Jost and Scott,

This is an interesting debate on a couple levels. Are we measuring the
girth and spread in the manner we do, simply because it is how we have
always did it? Or how some other authority measured them in the past?
We need to be thinking about what is the best way to take these
measurements. I have no personal investment in the methodology
supported by Paul Jost, and I have no personal investment in the
methodology argued for by Scott Wade. I would like to see a civil
reasonable discussion of the issue by anyone with an opinion to express.
Why is one way better than another?

Ed Frank
RE: Measuring multi-trunked individuals   Paul Jost
  Nov 24, 2004 20:17 PST 


It just seems inconsistent to me, whether or not a standard specifies that
it is acceptable, to measure the height of one stem, the girth of another,
and the spread of yet two more stems, especially if they are not joined
above the surface of the earth. It tells you little about the growth
potential of individuals, especially if the numbers are mixed with
measurements of purely single-stemmed individuals. In this case,
comparisons can't be made and declaration of championship status should be
questionable even if it is valid by the definition of the rules. I know
that several of us on the list do not nominate trees that appear to be
multi-trunked to state and national lists. If the stems are not common above
the surface of the earth, then how can you truly be sure that they all
sprouted from the same seed and not several seeds that fell near each other
and possibly became root grafted over time. 

Clones in the form of root
sprouts also should surely be declared individual trees. With some trees,
when branches contact the ground, they will root and begin a new vertical
stem. By some definitions, these would be the same tree. If the original
connection to the parent tree dies off, then the tree becomes it's own
individual. For the purpose of measuring, you have to draw the line
somewhere, and a common point of contact at the surface of earth seems to be
the most logical one to determine the extents of an individual tree.
Especially since we measure with respect to the surface of the earth with
height and circumference at breast height above the earth. It is the common
reference point - the point that I believe that Colby called "the spot where
the acorn sprouted." These are my opinions, not necessarily those of ENTS.

Paul Jost

RE: Corylus, measuring multi-trunked "individuals"
  Nov 25, 2004 04:30 PST 

No problem on my end. I enjoy debating, and learning how others view an idea. I am one of those folks whose feelings are seldom hurt by opinion. I am going to see the state champ Crack Willow (Salix fragilis) this weekend in Cambria county Pa. while we are visiting the in laws. 

A line has been drawn in the past, on how to measure these trees. I , being fairly new to tree measuring, am simply questioning why the entire plant isn't considered. A line has to be drawn somewhere, obviously, due to the nature of some species occupying an entire forest, and having the same DNA. As long as we don't get into name calling, my feelings won't be hurt, I assure you. You could probably even call me a few names too!

I don't have a ton of time to reply, as we are leaving for Thanksgiving. I would like to talk about this some more later, and get into enclosed bark on multi-trunked trees that have become one tree, and trees that graft together when they touch. Talk to you soon.

Have a nice Thanksgiving.


Different Rules for measuring
  Nov 25, 2004 05:58 PST 
Ed, Paul, Scott, et al:
     I second the call for good debate on the subject of measurement methods and rules, but I would hope we don't again get caught up in the rules used by American Forests or the individual states. The rules we should be most concerned with most are the ones we devise for ourselves.

     As a member of the moribund American Forests committee to improve the rules for measuring champion trees, I do have a continued interest in the reigning system of rules, simply because so many people use it and I do get called upon to measure candidate champions. However, the AF formula is by necessity a comprise solution to judging "bigness" in trees. We shouldn't forget that. The formula obviously doesn't measure trunk and limb volume and it does favor open-grown over forest-growth forms.

   As for my committee role with AF, I think I've finally given up on trying to fine tune the rules to what remains a fatally flawed process. My great friend Colby Rucker had come to much the same conclusion. I'm willing to acknowledge the public promotional good served by the champion tree programs and will continue to support the one here in Massachusetts. And obviously, when measuring a tree for the state, I use state rules. But if asked my opinion about the validity of the system, while diplomatic, I do point out its flaws and let it stand at that.

    It is important for us to remember, when it comes to the business of ENTS, we are not obligated to create a system that anybody can use. Our methods are not for the mathematically challenged.  We are dedicated to achieving an ever higher degree of accuracy in our measurements of individual trees principally so that our data will be of research value and will provide posterity with the best available statistical record of the sites we study.    

     If the above comments sound aloof, I would emphasize that those of us who co-founded ENTS weren't, and still aren't, about elitism. We wanted ENTS to serve many purposes and have the broadest possible membership - except, and it is a big except, when it came to measuring trees. In that mission, we were all very clear. In particular, we weren't going to make the often sizable errors that can result from using various forms of similar triangles or the tangent-based method to measure tree height. Thanks to our persistence, lots of computer diagrams, several tree-measuring workshops, and the support of stellar scientists like Dr. Lee Frelich, we are attracting larger numbers of serious tree measurers to our ranks. That trend should continue.

Re: Different Rules for measuring   Phil LaBranche
  Nov 25, 2004 11:01 PST 


   While I don't have a lot background/experience in the measuring
department yet, I have been following the debate on the multiple stemmed
trees/shrubs. I totally agree with you in that we need to consider all of
the tree for girth and such, be consistent with our methodology, and remain
as scientific as we can. If the method is to measure one part of the tree
for one classification, but all of the tree for another, that doesn't seem
consistent or scientific. It should either be all or none, generally

multi-trunked trees
  Nov 25, 2004 19:09 PST 


    A couple of years ago, I began concentrating on willows, silver maples, cottonwoods, pin oaks, green ashes, and other species growing in and around wetlands and on the banks of rivers. It quickly became clear that we needed a category for naturally coppiced trees, best illustrated by silver maple. I will say straightforwardly that it seems strange to measure only one stem of a natural coppicing form. The problem that American Forests forces on itself by trying to have one size fit all and by treating tree measuring as a game the whole family can play should never be our course. More on this later.

RE: Measuring multi-trunked individuals
  Nov 29, 2004 19:16 PST 
Paul Jost, Ed, Will

I have read Will's guidelines and agree with them for the sake of measuring for ENTS. I still have reservations on the large shrub/small tree. I look at a plant as a system, I don't stop at the ground level. I agree that the ground is a good standard for measuring. If this Corylus had been in the woods, I may have looked at it differently, but it was in a maintained area. It was evident that it was one plant. I believe part of the definition of a tree is 3" diameter at BH. Consider this. A plant is encountered that has a normal multi-trunked habit, would it be feasible to average the number of stems over three inches to represent the mass of a specimen, and then include the height of the tallest stem, and the entire spread? Maybe an identifier for how many 3" stems there were? This is just something I was thinking about today. I am trying to represent the entire mass of a plant. This would be for this type of plant only, and not large single stem trees. Would we list trees by habit, and then how they are to be measured?

When I measure for Longwood gardens on their "big tree tour", I am often pressured to measure multi- stemmed large trees (birch linden magnolia) at a height below 4.5BH, when I can see the enclosed bark lines running down past that, or there is a gap between one or two of the stems. I want to measure the largest stem at 4.5 BH, they want to drop down to the narrowest spot of single trunk below 4.5 BH. I don't like to measure low on a large tree, as I think it misrepresents the size. I am rambling now. Please tell me what you think.