| Weekend
Follies |
Robert
Leverett |
| May
16, 2005 08:00 PDT |
ENTS:
Tree measuring took place at 4 locations that
past weekend for yours
truly. First there was MTSF in Charlemont on Saturday AM, second
there
was Monica's woods in Florence and Look Park in Northampton on
Sat
evening. Then there was Monore State Forest in Monroe on Sunday.
The
measuring was incidental to other scheduled activities and for
the most
part I just tried to make observations about some of the forest
communities I saw and the role of particular species in those
communities.
In terms of new tall trees, the only
noteworthy trees in Mohawk I
measured was a hemlock at (115.5, 5.6) and a white ash (125.7,
6.1).
Nothing special about the hemlock, just a tree I had never taken
the
time to document near the entrance of Mohawk. The white ash is
in the
boulder field on Todd.
At Northampton's Look Park I measured 4 trees
to report: N. red oak
at (104.4, 10,9); Shagbark hickory at (112.1, 5.2); and sugar
maple at
(105.4, 10.5), and a white pine at (133.4, 7.1).
At Dunbar Brook in MSF, a white ash
caught my attention at (126.3,
7.2). Many worthy yellow birch there beg for attention.
In Monica's woods, I measured another
northern red oak at (102.7,
6.9). Monica's leading white pine is now 130.6 feet tall
courtesy of a
better measurement as opposed to new growth. At this point the
new
growth is around 2 inches as observed on smaller pines in the
vicinity
of the tall pine.
Is there anything to be learned from the
above mix? Well, not much
that I can state with confidence. But there are some interesting
observations I'd like to throw out for discussion.
The skinny 112-foot shagbark hickory in
Look Park grows within
spitting distance of a much larger N. red oak. Both have plenty
of
growing space and are located at the bottom of a hill next to a
ball
field. Growing conditions for the two trees are virtually
identical. I
didn't measure the oak, but it is about 96 or 97 feet tall and
close to
10 feet in circumference. The hickory is still going up, but the
oak has
flattened out. The oak is a much more imposing tree. The hickory
is a
bean pole, hardly noticeable except to the fanatical like
myself.
When lumberman say that hickories grow
slow, I interpret that to
mean in diameter-volume growth relative to species like oak and
maple.
It certainly isn't true for height growth. It is my unremarkable
observation that for competition between shagbark hickories and
N. red
oaks, can we typically expect oaks to be the larger trees, often
much
larger. That would certainly be true for southern New England.
However,
it is also my observation that the shagbarks will often be the
taller
trees - to a point. Certainly not everywhere. In Ice Glen, the
few
shagbark hickories top the more abundant oaks to reinforce my
observation. But in MTSF, the more abundant oaks top the few
shagbark
hickories. There isn't any competition. Oaks win. In Arcadia
Wildlife
refuge on the flood plain of the Manhan River, the shagbarks
will
slightly out-perform the N. reds in height and the N. reds will
slightly
out-perform the hickories in girth. So what genetic factors are
involved
with N. red oaks and shagbark hickories to account for the above
growth
patterns?
The white pines of Look Park, Mount Tom
State Reservation,
Easthampton, Smith College Campus are gradually edging upward
with more
trees in the 130 to 135-foot height range. But with a single
exception,
hunt as I may, I just can't find 140-footers in the Connecticut
River
Valley? Why is that? There's plenty of white pine habitat and
stands/groves in all kinds of growing conditions. By contrast,
we can
find them in a number of places in the Berkshires and Taconics.
Why is
that? We can go farther north into New Hampshire and find some
140-footers in the Connecticut River Valley corridor. What
changes from
Mass to New Hampshire?
As more white pines enter the 75 to
125-year age range in both the
valley and hill provinces, the picture may change slightly, with
the
mountains becoming slightly less dominant, but as it stands now,
for the
current state of environmental conditions, the mountainous
regions of
Massachusetts grow taller white pines. There's no contest. Is
there more
air pollution in the valleys? Is there less protection from
wind? Has
the land been abused so much more in the valley province that
tree
growth has been reduced for white pine? Perhaps mountainous
environments act as better aquifers that the river valleys,
metering
out the water more consistently. However, the height growth I've
alluded
to may not hold for diameter growth. I see has many large
diameter pines
in the valley as I do in the mountains.
The core of Monica's woods comprise a
small area of about an acre of
tightly packed N. red and black oaks with a few white pines,
tulip
trees, yellow and black birch, hemlock, red maple, and a lone
white ash.
By expanding the area to include a small part of the adjacent
properties, we can add white oak, and sugar maple. But within an
area of
about an acre, Monica has a cluster of 5 or 6 N. red oaks over
100 feet.
She has 5 tuliptrees over 100, and 5 white pines. The white
pines are
in two locations. If the pines and the tuliptrees were removed,
would
the oaks have made it to 100 feet? There is also an ash and a
red maple
over 100 in the tight cluster. A hemlock close by, but not
influenced by
the pines and tulips just makes 100. It seems to be acting
independently.
There are lots of questions we can
raise to investigate the growth
performance of the species we see in the combinations we
observe. One
observation that seems incontestable is that competition with
white pine
and/or tuliptree forces other species to grow taller in southern
New
England. So in addition to abundant water, deep soil, and
protection
from wind, we must factor in what's growing next to what to
explain
achievement of various height thresholds. Then there is black
cherry. It
seems more independent. To an extent sugar maple seems to be
independent of other species, though influenced by its own.
Perhaps a more interesting question
might be what species aren't as
influenced to grow taller by big performers like white pine and
tuliptree? I suppose white ash should be included as one of the
big
performers in western Massachusetts.
Bob
Robert T. Leverett
Cofounder, Eastern Native Tree Society
|
| RE:
Weekend Follies |
Robert
Leverett |
| May
16, 2005 10:21 PDT |
ENTS:
Oops, I hit the send button too quickly
in the last e-mail.
At the end of the e-mail, I
introduced the white ash as another big
performer in Massachusetts. I wanted to raise the question about
its
effect on other species in driving up their heights above what
we might
otherwise expect them to be. Question is, what do we expect them
to be?
An apparent factor in the effect
of the big performers on other
species is density of the biggies. Where white pines dominate in
western
Massachusetts, all other species have to try to play catch up -
with
little chance of actually doing so, I might add. Unless another
species
has gotten a head start, the white pines limit the growth of
other
species that are jammed in among the pines. Nothing here not to
be
expected. But what are the effects of the competition?
Well, one immediately apparent
effect is that species like red
maples can have a very high height to diameter ratio. Reds mixed
in
among pines can surpass 100 feet in height while being little
more than
3.5 to 4 feet in circumference. These maples may be tall and
have a high
height to diameter ratio, but they are hardly champions by any
other
criteria. They are bean poles with very little growing room. The
height
to diameter ratios of these trees is less an expression of sheer
growing
power than that of raw survival. So high height to diameter
ratios of
red maples growing among pines are not necessarily expressions
of
excellent site growing conditions.
What can we expect out of red maple
where the species has a little
more growing room? Well in the Berkshires, a red maple that is
in the
height and girth range of (105 - 115, 8.0 - 9.0) is a real
beauty.
Everybody who recognizes the species takes notice of these red
maples.
It is my contention that trees in
this height-circumference range
combination reflect the best that the species can do in my neck
of the
woods. If we find taller specimens in western Massachusetts than
above,
they are typically smaller in girth and driven by intense
competition
with one or more of the big performers. They may be short-lived
and
hardly of champion status along traditional lines of comparison.
A
100-foot tall red maple that is only 4 feet in circumference is
really
not impressive to look at.
This line of thinking suggests that we
examine species profiles more
deeply. For example, of 37 red maples in MTSF measured to over
100 feet
in height, they are distributed circumference-wise as follows.
Circ Rng(ft) >100 ft
in
Hgt Cum # Pct
Under 4.0 2.0 2.0
5.4%
4.0 - 4.99 2.0 4.0
10.8%
5.0 - 5.99 6.0 10.0
27.0%
6.0 - 6.99 13.0 23.0
62.2%
7.0 - 7.99 6.0 29.0
78.4%
8.0 - 8.99 6.0 35.0
94.6%
9.0 - 9.99 1.0 36.0
97.3%
10 and over 1.0 37.0
100.0%
What is immediately apparent is that the
vast majority of 100-footer
red maples in Mohawk fall within the circumference range of 5.0 -
8.99
feet. One can see the limits to red maple performance. An
obvious
conclusion is that there are many 100-foot tall red maples in
Mohawk,
but few over 9 feet in circumference. The diameters of the
majority of
100-footers vary from 1.6 to 2.9 feet. Only 16% of those
measured fall
outside this range.
If one has the idea that one will find an
abundance of red maples
that are both large and tall in Mohawk or that the tallest are
also the
largest in circumference, one will be surprised to find that the
species
doesn't behave that way at all. Driven by competition to grow
tall
first, the red maple then gradually fills out, but only to 7 - 9
feet in
circumference. In maturity, crown breakage tends to reduce its
height,
so that trees in the 5 to 9-foot circumference range will
dominate the
tall class. Increase the height threshold to 110 feet or more
and 88%
fall within the circumference range of 5 - 9 feet. Go to 112
feet or
more and 100% fall within the 5 - 9 range.
The above height - circumference profile of the red maple along
with a description of the conditions where it reaches particular
heights/circumferences allow us to nail down the performance of
the
species quite nicely. This knowledge has value. We are able to
determine
what a species CAN do when left alone in various growing
conditions. If
we compare what it can do to what it IS doing in, we can assess
the
impacts of various kinds of human and natural activity.
Bob |
|