Dendrochronology Projects    Edward Frank
   Oct 17, 2006 11:21 PDT 

You have a publication in press:

Pederson, N., A.W. D'Amato and D.A. Orwig. In Press. Central hardwood natural history from dendrochronology: maximum ages of rarely studied species. Proceedings of the 15th Central Hardwood Conference.       

I don't see any citations from this paper on your current Old List. When will the publication be out and will it add new numbers to your Old List? (maybe I am missing them on the current list).

I think it would be a worthwhile project for someone to undertake to try to measure "old" examples of as many different eastern species as possible.   I am sure It is difficult to examine the structure and processes going on in old growth forest without any idea how long most of the species of the trees in the forest can live.

How would someone go about this project - permissions and funding not withstanding. I would make a list of all of the major species without ages found in eastern forests. I would then annotate the list with notes on where the largest specimens of those species are found, and old growth areas within the dominant range of the species, and third old growth areas in which the species was known to occur.   The ENTS list for example has people familiar with sites scattered across the eastern US and many people likely could suggest specific sites worth examining, likewise some of the dendro lists.

Next I would visit a particular site with the goal of collecting cores from key species I thought would be present on the site. And second I would collect cores from any serendipitous specimens of other species that appeared to be of great age. Places like Tionesta where it is know that hemlocks have been dated to 555, would be a good site as the potential for other trees of age would be there. There likely hasn't been a widespread decimation of the forest since the hemlock sprouted.

Site information, sample location, photos, notes, etc would all be collected...

You have done a lot of this type of work and are expert on the subject.
How would you suggest such a search be structured?

The specimens would then need to be processed. What equipment is necessary to do tree ring counts? Obviously sanding paper of various grits down to extremely fine, a microscope to examine cell structure, some computer power to process data - many of the dendro programs can be downloaded from the internet. For example if I were to set up the "Reynoldsville Tree Ring Laboratory" [Like the one in Ethiopia] what would be needed equipment wise?

The person would need training in what they were doing, and a decent selection of reference materials. You have participated in these dendro workshops - how are they? Do they give a good enough overview in actual application in the week or two they are run to make someone reasonably competent in counting rings and doing cross-correlations?

I am just curious about the field and the equipment and processes involved. When is the next dendro field camp and where? Do you have a website?

Ed Frank
Re: Dendrochronology Projects   Robert R Bloye
  Oct 17, 2006 13:23 PDT 

Greetings to all scattered ENTS:
          This current thread hits me right smack in the middle of my PhD
research at the Forestry Department of Michigan State University.
I'm working up the fire history of a section of Michigan's Lower Peninsula
using dendrochronological techniques.
         Might I refer all dendrochronologically-interested parties to a
goldmine of a website?....

         "The Ultimate Tree-ring Pages" are just that. Techniques,
equipment, bibliographies, on-going research [in some very surprising
         Links to an international database of tree-ring series are included
there as well as links to dendrochronologists across the USA and the world.
Also consider contacting a local member of the Tree-ring Research
       There are as many semi-informed amateur dendrochronologists out
wandering around as there are people who think they know how to measure tree
heights. The ENTS, wonderful folk as we are, are the refreshing difference.
       Holler if I can help...

                            Robert R. Bloye
Re: Dendrochronology Projects   Neil Pederson
  Oct 17, 2006 21:45 PDT 

The old trees, most all of them I would guess, were discovered through
serendipitous research [if that is a word]; a systematic search for old
trees has been limited. I am unsure of who would fund it. But, you are
correct. It seems some locations might have a higher abundance of older
trees than other locations. Going through Will Blozan's GSMNP collection, I
note several old individuals in a few species within the same general
location. I don't know if this thought, however, would hold up to a
scientific examination. Given limited resources [$$, time], this is likely
the way most old trees would be found; unless Bill Gates or someone like
that would like to fund this type of research.

Fieldweeks are great. You would learn the basics enough to crossdate. Next
yr's fieldweek is in the Smoky Mtns. I will be one of the group leaders:

You can get microscopes on eBay for $500-800 I hear, refurbished ones for
$900+ and new ones for $1200+. Measuring systems go for ~$2k. An increment
borer goes for $200-300, depending on different specs. You'd want two; some
borers break rather easily.

Thanks Robert for direction to Henri's pages. All the other supplies one
needs is there.


ps - the Pederson, D'Amato, Orwig paper is still in press. It is used many
times on Eastern OLDLIST.
Re: Dendrochronology Projects   Robert R Bloye
  Oct 20, 2006 08:05 PDT 

Greetings to all:
       The ENTS are doing a fabulous job raising the awareness for
mensuration skill in all of us tree-huggers out here. Some of the big trees
I've re-measured in Michigan for our state coordinator of the Michigan
Botanical Club Big Tree program were horribly off and are now corrected.
Estimating tree heights by sighting off a wet thumb struck in the air seems
not to have been too accurate in several cases.
       In a similar sense, putting an increment corer in the hands of some
folk is just as bad or even worse. Dendrochronology is way more than mere
ring counting, as most ENTS are aware.
       I sat through a graduate presentation dealing with an aspect of
forest ecology in Ann Arbor [ the university shall remain anonymous] where
the innocent presenter made the most interesting claims from his increment
core collection efforts. Several of us Michigan State University foresters
quietly took him aside later[at a pub] and instructed him in the way more
perfect. He got more training in dendrochronology and is now in his right
       Tree height and tree age do not correlate too tightly.
The current discussion among ENTS about tree ages is beginning to bring this
out....way to go!....

Re: Dendrochronology Projects   Neil Pederson
  Oct 20, 2006 08:48 PDT 
Bob, ENTS,

I am not yet unable to sum up all of the advances of dendrochronology,
though Dave Stahle's 'Megadrought, Megadeath' is a good start as is Ricardo
Villalba's work on climate and stand dynamics in Argentina and the
similarities he found between climate in North America and South America is
pretty amazing. There are so many others like Jan Esper in Switzerland, all
of the advances by many scientists in the tropics [too many to keep track
of] and Henri Grissino-Mayer's and Charles Lafon's fire history work in the
southern Appalachian Mtns. I hate to make a list because I will undoubtedly
leave [and have left] many others out. There are so many!

Here's a thought to consider: just over 10 years ago there were less than a
handful of tree ring scientists with Ph.D's in the eastern US mostly focused
on climate and stand dynamics. Now there are well over 30, I'd bet [have
trouble keeping track actually - Robert is a good example, actually - Hi
Robert]. We are literally standing at the bottom of a building wave of tree
ring research in the eastern U.S. The topics are so diverse now, too. Cicada
outbreak reconstructions (Jim Speer, Ind. State), carbon dynamics (Amy
Hessl, WVU), ultra-long and ultra old oak chronologies (R. Guyette & Mike
Stambaugh, Mizzou), ...... It is an exciting time in the field.

BTW, when Friendly's did a corporate downsizing on their sundaes in the
late-90s, I knew our civilization was beginning its inevitable decline -

Re: Dendrochronology Projects   Don Bertolette
  Oct 20, 2006 19:42 PDT 
Wonderful 'blend' of some of my favorite topics...watermelon sherbet and tree measuring! But a sticky proposition, when accomplished simultaneously!
Of course out west, we've locally got Pete Fule of the Ecological Restoration Institute, who has a great supporting dendrochrono lab for ERI's prodigious restoration work/research, and at U of A's Laboratory of Tree-ring Research (great webpage at,, where such topical hypertexts as dendroarchaeology, dendroclimatology, dendroecology, dendrogeomorphology, dendrohydrology, dendroisotope chemistry, and others abound) we've Tom Swetnam to call upon, among a burgeoning throng who built upon the Arizona claim to dendrochronology heritage! A snippet about A.E. Douglas follows, surely a Renaissance man for his time and place (note South American start!):

    Andrew Ellicot Douglass was born on July 5, 1867 in Windsor, Vermont. He was educated at Trinity College in Hartford, Connecticut, and graduated with honors in 1889. After his graduation, he began working for Harvard Observatory. He served as the chief assistant on Harvard's Boyden expedition (1891-1893), which founded the Harvard Southern Hemisphere Observatory in Arequipa, Peru. After returning from Peru, he met Percival Lowell in Boston. Lowell hired Douglass to travel to Arizona to determine where the best place in that territory would be to build an observatory. Douglass traveled throughout Arizona in 1894, eventually settling on Flagstaff as the best location. He chose a spot on a mesa outside of town and supervised the construction of the dome which housed the 18-inch telescope that he and Percival Lowell used to observe Mars.
        After the founding of Lowell Observatory in 1894, Douglass stayed on for seven years as Percival Lowell's chief assistant. During this time, he provided a great quantity of data regarding Mars which Lowell used to support his theories about the existence of an intelligent, canal-building Martian civilization. Lowell and Douglass, however, clashed several times over Douglassís opinion that Lowell used data selectively (and thus unscientifically and inaccurately) to prove his theories. Lowell eventually lost patience with Douglass and sacked him for this opinion in 1901.
        After his termination, Douglass stayed in Flagstaff until 1906 teaching Spanish, Spanish History and Geography at the Northern Arizona Normal School, now Northern Arizona University. He also ran and won the race for probate judge - now called the Justice of the Peace - in 1902. During his time in Flagstaff, Douglass became interested in tree rings, and specifically in using tree rings as a record of previous solar cycles as well as a method of predicting future solar cycles.
        When Douglass relocated to Tucson in 1906, he began teaching at the University of Arizona. His most important scientific accomplishment while in this position was the creation of dendrochronology, more commonly known as the science of using tree rings to determine the age of a particular piece of wood. He finally established an unbroken sequence of yellow pine (or Ponderosa) tree rings stretching far enough back into history to conclusively date ancient Native American structures in 1929. This accomplishment was widely hailed as one of the most important in archeology by both scientists and laymen alike.

Re November, we're definitely on, details to come soon!
-Watermelon Don...;>}