Where are the limits?   Robert Leverett
  May 19, 2004 07:27 PDT 

       With the confirmation of enormous volumes of the Middleton live
oak and the Sag Branch tuliptree by Bob Van Pelt as currently the
largest volume hardwoods measured in the East and with Will's new
154.7-foot red spruce and Jess's confirmation of the 168.2-foot pignut
hickory as currently the tallest IN THE WORLD for those two species,
we're riding a wave of firsts. Jess Riddle obviously has a phenomenal
area to search and he's just the person to do it. Will has possibly the
finest temperate hardwood forest in the northern hemisphere in which to
roam and confirm new champions. He also has the tallest coniferous
forest in the East in which to do the same. Meanwhile Dale Luthringer is
going gangbusters in Pennsylvania, giving us an increasingly detailed
look at the taller forests in the Allegheny plateau region and on the
border of lake Erie. Through a mountain of work, the Tree Amigos have
verified 61 white pines in MTSF that top 150 and most are still growing
teenagers - lots of potential yet to realize.

       Well, the list of accomplishments goes on and on and just when we
think we've exhausted the possibilities, we discover a new site and so
it is here in Massachusetts. My son Rob took the time to look carefully
at Laurel Park in Springfield MA and it blew him away. Very large red
and white oaks. Very large black birch. Tuliptrees. Oh boy! So sometime
in the next week or two, we'll begin roaming Laurel Park and documenting
its arboreal delights. As Tom Diggins often says, so many trees, so
little time.

       Where and to what do the continuing ENTS discoveries point? All
these super trees. Well, of course they tell us something about species
potential, but not just of isolated individuals - the circus freaks, so
to speak. We are gradually homing in on what a species can do over its
full geographical range, and more importantly, with what probability.
That's my current focus.

       We shouldn't be satisfied to just know where the largest pines
are and the individual dimensions of the champs. We should be able to
answer questions as to how likely or unlikely any particular range of
dimensions can be achieved for a particular species, what's common and
what's not for a species in a particular growing habitat.

       While a lot of us have rough ideas about species growth potential
over fairly broad ranges, we have a long way to go to fine tune our
understanding even for a relatively local area, an area of perhaps a few
as ten of thousand of acres. Each new discovery can make previous
notions obsolete and the job of fine tuning our understanding of species
potential can seem more and more elusive.

       But in actuality, we're making enormous strides. However, those
strides have required that we first served our period of apprenticeship,
even though we had to be apprentices to ourselves. We also had to rid
the business of tree measuring of some real handicaps. We have had to

1. The hobbyist status of big tree measuring that has been fostered by
the champion big tree lists,

        2. The mistaken perception that big tree knowledge is vested in
the lumber producing occupations,

        3. The unfortunate belief that current historical accounts and
data are sufficient to understand species potential,

        4. The understandable but erroneous assumption that governmental
organizations and officials and/or academics have the answers,

        5. The industry-minded opinion that it's all goofy stuff - the
only real purpose for a tree to serve is for construction, paper, or
wood chips. End of story.

        I used to get irritated by people (including myself) who fell
prey to any or all the above notions, but have become more tolerant in
my old age, partly because ENTS has made lots of converts and we don't
have to any longer to yell so loud to be acknowledged. Lee Frelich may
have had the most to do with our growing acceptability in the East by
making it safe for other PhDs to follow suit. As proof of our new found
acceptance, Friends of Mohawk Trail State Forest
has concluded two long term special research permits with the
Commonwealth of Massachusetts. Both permits recognize our role in a
couple of areas of research that other Massachusetts organizations and
institutions could claim as equally within their purview. However, in
terms of inventorying, mapping, and documenting old growth on public
lands in Massachusetts, we ARE it. Exciting times are upon us.

      So now maybe we can roll up our sleeves and get down to business -
no longer any need for internet admonishments of the doubters or
pretenders to the throne. So what's next? The impending research and
associated data collection efforts for MTSF will concentrate in the
following areas:

     1. Continued perusing the area looking for the superlatives (can't
easily break us of that),

     2. Development of increasingly accurate methods for measuring
annual growth,

     3. Testing different independent variables for ease of measurement
and tracking,

     4. Developing statistical distributions that we can ultimately use
to compute the probabilities associated with the achievement of
different growth thresholds.

     It is the last area that will occupy the attention of several of us
over the coming summer, because if we can assign realistic probabilities
to growth potential, we can convey to others how rare or common a
growing habitat for a species currently is or could be under existing
environmental conditions. For example, the population of white pines
that reach the dimensions of 12 feet in circumference and 150 feet in
height is very small. In Massachusetts, we currently have only two
single-stemmed pines that make reach this threshold. We have one
documented in New Hampshire. There are several in Pennsylvania and quite
a few in North Carolina. Michigan has had a few in recent years as has
Wisconsin, I suspect. New York has one or two and so the numbers go.

      From these numbers, it is clear that the likelihood of a white
pine eventually reaching the 12-150 combination is low to very low. In
some areas, the probabilities is extremely small, practically zero. In
highly favorable growth areas that include several to many 150-footers,
it is unclear how much natural stand thinning is needed to allow good
diameter growth along with continued height growth. Presumably, when we
see both good diameter and height growth continuing at a location, we
have identified a top white pine site, but for how long? Making
predictions about maximum potential is risky when trees are only 50
years old - unless there is a prior site history to turn to. That's
where MTSF becomes so valuable as a research site.

     In MTSF, we are blessed with several pine locations in the 45 - 60
year age class, several in the 90 - 120 class, and a few in the 135 -
175 class. We can study 3 sub-populations, 50, 100, and 150-year-old
age classes. We can even add a few in the 175-year age class.

    We want to be able to compute probabilities with which pines achieve
various size thresholds within the three age classes. To do this we have
to have population numbers. How many pines do we have on each site
within each age class? Answering that question has become the focus of
my attention. As some general observations, at this point 50 stems per
acre appears common for the less dense areas and 100 for the more dense
areas. Small areas will have 150 to 180 pines per acre. However, these
densities are not sustained.

     Based on what we've mapped as white pine habitat, we currently
believe that there are between 5,000 and 10,000 pines in MTSF. We are,
or at least I am, very shaky on this number. We'll see how our
estimates/calculations evolve over time. My current guess is about