Broad Habitats, Patterns, and the Return of New England's Forest   Robert Leverett
  Nov 17, 2002 10:16 PST 

        The Connecticut River Valley is a region blessed with geographical
features that provide diverse habitat for tree species. Glacial deposits and
forms are everywhere apparent to the trained eye. Much older geological
features that break up the valley include the Mount Tom and Mount Holyoke
Ranges and the Mt Toby uplift. The hallmark of the Valley is its deep
alluvial soils and terraces of glacial Lake Hitchcock. To the east of the
Valley there is the Pelham Hills that rise above the Valley 1,000 to 1,100
feet. To the west, the Berkshires rise even higher to elevations of 2,000 to
2,500 feet above the valley, but the do it gently. With the exception of the
river gorges, the Berkshires are more plateau than mountain.

        Major feeder streams to the Connecticut Valley include the
Westfield, Manhan, Mill, Deerfield, and Chicopee Rivers. If one stays
within the river valley region, the prominently tall tree species (120 feet
or more) turn out to be surprisingly sparse. they are limited to white pine,
sycamore, tuliptree, and cottonwood. White ash may belong in the club, but
that noble species reaches its glory in the river gorges and on the
mountain slopes, not in the broad river valleys. What reigns over the valley
province? Silver maple, sugar maple, the hickories, the ashes, northern red
oak, pin oak, black locust, and hemlock commonly reach to 100 feet or more,
but between 100 and 115, they stop. A few other species like white oak and
beech on occasion reach 100 feet, but struggle mightily to reach 110. If
Mount Tom and Mount Holyoke are included, on occasion black birch makes it
to triple digits. It is as though giant pruning shears maintain an upper
limit to all but the 4 species mentioned above.

        A dozen species grow to large girths in the Valley, surpassing their
mountain cousins in number, but they don't reach to the greater heights of
the mountain trees. The differences are pronounced enough that they cannot
be disputed. The explanation for the differences can be. One might expect
that the low, broad Connecticut River Valley would hold title to the biggest
and tallest trees. It does hold title to the biggest and the most common big
trees of the valley are the cottonwoods and silver maples with the
exceptions of a few gargantuan sycamores that form a class all their own.
White pines and tuliptrees can reach impressive sizes, but tuliptrees are
very few in number. The white pines don't quite rival the cottonwoods and
silver maples for abundance of large diameters.

        I suppose in some context the height puzzle makes sense, but that
context has not yet been determined. Why don't more of the white pines of
the Connecticut River Valley match their mountain cousins? The white pine,
unlike the tuliptree, is not pressing against any range boundaries in Mass,
just altitude and that would seem to work against the mountain pines, but
doesn't within the first 1,500 feet of elevation. In the central Berkshires,
the Bryant pines grow at elevations of 1,300 to 1,400 feet. The great Henry
David Thoreau pine in Monroe SF grows at just under 1,300 feet. At 2,000
feet above sea level, you see few pines in the central and northern
Berkshires. The ones you do see aren't much to look at. Above 2,000 feet is
the domain of spruce. So within 600 vertical feet, the white pine goes from
a tree that can reach 150 feet to a species that all but drops out. In the
Connecticut River Valley, white pine is common, but individual trees that
make it to 130 feet are encountered infrequently. Judging from historical
accounts, with due allowance for hyperbole, I think we would have seen
whopper pines in colonial times. I don't know how abundant they would have
been. That is Charlie Cogbill's department, but what we would have seen
would have been very impressive.

        Is the valley region worn out? Overused? Have we lost the best of
what once grew in abundance? The flood plain trees that exist in the same
environments as in colonial times and mature much more rapidly are the big
ones. They may have been less impacted by human use. That may speak to the
impact of overuse of the land by European Americans. I see reasons to
believe that.

        The regions harboring the most exceptional Berkshire trees are
usually areas with a European history that is 100 to 150 years shorter than
the European history of the river valleys. They are also areas that have
been cut less frequently and areas relatively rich in pockets of old growth.
Is all this coincidental? Well, if you believe some of the voices
representing timber interests, it doesn't matter much what you do to New
England's woods. Supposedly they bounce right back. Well, maybe they do
bounce back, but not RIGHT back. It's a complicated mix. I'm thankful that
we have scientists like Lee Frelich and Charlie Cogbill to sort out and
measure the many variables, which ones are redundant, which ones exhibit a
major influence, which ones work only in combination with others. It's
enough to give one a headache.

        One thing I do know is that the numbers that we're collecting don't
lie. The valley doesn't grow 130-foot tall red oaks and apparently can't.
Some areas of the mountains to the west can. The valley can grow giant
sycamores. The mountains can't. Both valley and mountains should be able to
grow 150-foot white pines, but none achieve that distinction in the valley
and so far I've seen little evidence that any will achieve that distinction
in the foreseeable future. A total of 35 have already achieved that
distinction in the mountains. Sugar maples get relatively large in both
valley and the mountains. In some areas of the mountains they can reach 130
feet. In the valley, they can't. Native tuliptrees in the Connecticut River
Valley region reach modest sizes for the species. They appear maxed out at
120 to 130 feet. At similar ages, farther south, and even farther west, they
would be able to add another 10 to 15 feet of height. Why is that? Silver
maples grow like weeds along the Connecticut River and its tributaries until
those tributaries reach the hills to either east or west. Then the silver
maple drops out very fast even in what appears to identical habitat. It is
apparent that different species can be extremely sensitive to very small
changes in environment. As a consequence, one can list fact after fact
after fact that appears incongruous.

        What does it all mean? Well, there is a lot more to understanding
our native trees and the habitats that they've adapted themselves to than
can be gained from simplistic views of New England's trees and tree
habitats. So when I hear or read that we can do pretty much anything we want
to do to our forests and they'll come bouncing right back, pardon me if I
stay a bit skeptical.

Re: Broad Habitats, Patterns, and the Return of New England's Forest   Joseph Zorzin
  Nov 18, 2002 02:38 PST 

----- Original Message -----
From: Robert Leverett


          I suppose in some context the height puzzle makes sense, but that
context has not yet been determined. Why don't more of the white pines of
the Connecticut River Valley match their mountain cousins?

The reasons you see greater heights in some mountain areas, is in my extremely humble opinion (being an extremely humble guy <G>) is as follows:

a.. protection from storms due to having higher ground around them
b.. difficulty of access to loggers, allowing them to reach greater age and greater height
c.. higher levels of soil moisture during hot, dry weather- from water higher up the slope often draining down the slope rather than straight into the ground since bedrock is often close to the surface
d.. sometimes, higher site index due to nutrients flowing down hill with the ground water