Sedona Canyon, Arizona
|
| Is This Old-Growth? |
Don
Bertolette |
| Sep
19, 2004 |
| Ed-
Attaching an image from my most recent outing...perhaps it will serve as a
point from which to launch a discussion on just what constitutes
old-growth,
and what makes a bush a bush (not intended to launch a political
discussion!) and a tree a tree. The foreground is a manzanita (Arctostaphylos spp),
the background the
redrocks of Sedona, and predictably enough, me on middle ground. I am
comfortable suggesting that this manzanita is pre-Euroamerican settlement in
origin.
I suggest that there is an analogy of this manzanita (and an oak of similar
stature and "soil" bank) to the more famous Bristlecones of the White
Mountains of Eastern Central California (attaining 3-4,000 years). Surely
they're old-growth? In my view, they belong to their own category, an
old-growth tree/forest that have attained their status from the "economy" of
their growth habit...they have adapted to conditions that are extraordinary
in their extremes - cold, minimal soil nutrients, incredible levels of
ultra-violet rays (10-14,000 feet, precious little atmosphere filtering out
the sun's rays), heat.
This probably opens up the bush/tree question, as there are those who
propose that the common creosote bush is among the oldest continuous
lifeforms (posited to create concentric "rings" as they
allelopathically
force their growth outwards).
Back to manzanita, I have not yet seen one with a singular bole high enough
to have a dbh, but numerous examples yield trunk diameters of a foot or
more. This specimen here is growing in precious little soil and able to
survive on very little moisture. Taken during the second week in September,
the temps were in the low 80's. Not unusual for the area to rise into the
90's, occasionally in the 100's.
-Don Bertolette, Sun, 19 Sep 2004
|
| RE:
Is This Old-Growth? |
Robert
Leverett |
| Sep
21, 2004 07:39 PDT |
Don:
Your make very important points. As I
know you would agree, the
definitions we adopt for OG usually incorporate science,
politics,
economics, and aesthetics. While our intent may be to
restrict the
criteria to science, I think the exigencies of the
situation usually
dictate otherwise. I'm struck by the practicality of Lee
Frelich's
definition that for him old growth is whatever the
resident authority
says it is. Lee then works within the context of that
definition to
explore the natural processes that shape the forest
environment - toward
a rapidly or slowly evolving system.
Perhaps you should become the resident
authority under the auspices
of WNTS. WNTS could become a repository for ideas,
models, and debate.
One can hardly not be struck by the difference between
environments that
cycle forests every 100 to 200 years as in flood plains
to rock and ice
environemnts that can allow gnarled bristlecone pines to
linger on for
5,000 years. Allowing for a 150 year cycle on a flood
plain, one cycle
of the bristle cones equals 33 cycles of the flood plain
environment. Of
course each environment has many cycles that play out
beyond the obvious
seasonal ones, but sometimes it helps to consider how
old growth
environments differ from one another as well as consider
the points of
similarity.
Bob
|
|
| RE:
WNTS: Are These OG Forest |
Edward
Frank |
| Sep
21, 2004 10:17 PDT |
ENTS,
Don presents a simple question about whether these
manzanita are trees
and whether or not they constitute and old-growth
forest. Behind this
simple question lies a variety of hidden questions:
1) Are these short manzanita considered to be a tree?
The hidden question is whether or not height is a
dominant factor in
determining whether something is a tree or not. I
don’t know. Is there
some structural or physiological difference between a
tree and other
types of vascular plants? Does something become tree
solely based upon
height? I know there are species of oak that are maybe a
meter in
height, are these trees or not? Other members of the oak
family reach
large size, so does it make sense that some are trees
and others are
not? Does it really make any difference?
The Oklahoma Biological Survey defines the terms as
follows: “There are
approximately 2,400 plant species in Oklahoma (Taylor
and Taylor 1994)
and about 330 are trees, shrubs, or woody vines. For the
purpose of this
document, a woody plant is defined as a plant that
retains some living
woody material at or above ground level through the
non-growing season
(several species of small cacti fit this definition, but
are not
recognized trees or shrubs). Categorizing a woody plant
as "tree",
"shrub", or "vine" is often
difficult and can appear arbitrary.
Distinguishing between a tree and a shrub can be
particularly difficult.
That is why it is not unusual to see descriptions such
as "small tree or
large shrub." In this treatment we have adopted the
following
definitions: a tree is a woody plant that is at least 10
cm (4 in ) in
diameter at 1.4 m (4.5 ft) above ground level; a shrub
is less than 10
cm in diameter at 1.4 m above the ground and usually has
multiple stems
or is clonal; a woody vine does not stand upright
without support but
climbs on other vegetation or sprawls on the ground.”
So as far as the OBS is concerned the main difference
between trees and
shrubs are their height. For the purposes of the WNTS
and ENTS I would
lump both trees and shrubs together as a single category
as the
separation between the two groups is arbtrary. Therefore
this manzanita
(Arctostaphylos spp) is a “tree.”
2) Does this population of trees, including both
manzanita and (oaks?)
Constitute a forest? Don says, “In my view, they
belong to their own
category, an old-growth tree/forest that have attained
their status from
the "economy" of their growth habit...they
have adapted to conditions
that are extroardinary in their extremes...” I have
been looking at
definition for various forest types.
Bob Leverett (Feb 10) wrote, “.. you raise some
interesting points. The
most intriguing to me concerns how we actually define
forests/forest
types especially today when so much human-created
disturbance has taken
place that impacts what we can do. How might we define a
floodplain
forest of say the Connecticut River at the latitude of
Hatfield,
Massachusetts, given the massive ecological changes that
have taken
place from the surrounding farms over many years? ...The
answer to the
question of what we include in a definition probably
depends on one's
profession. If so, what might be the differences in the
requirements of
a definition as seen from the perspectives of the
forester, forest
ecologist, plant ecologist, wildlife biologist, and
conservation biologist? Who would emphasize what as hard and fast
requirements of a
definition. Like everyone else on the list, I've read
plenty of
definitions of forest types/associations that are
oriented to species
composition. Some hint at structural features, but
usually only in a
very general way.”
Lee Frelich (Feb 10) wrote; “Minnesota Department of
Natural Resources
recently switched to natural community-based definition
for forest and
other vegetation. They used ordinations including trees,
shrubs and
understory plants to separate communities within each
region of the state. The ordinations were based on thousands of plots
where all trees
and plants were identified by Natural Heritage
Ecologists. Those plots
that fell together in clusters in multi-dimensional
ordination space
defined a natural community, and the characteristics of
those plots were
used in the descriptions that have now been published
(but its not on
the web yet).”
So clearly we can define this plant community as a
distinct entity. Is
it a forest? It seems to me what we define as a forest
or not a forest
depends on the density of trees in an area. In the
eastern US trees
often grow like weeds. The density of trees in an
eastern forests is
high. This is partially related to the age and species
present, but if
talking about mature forests a major factor is the
availability of
water. In drier climates there are savannah forests with
more widely
spaced trees intermingled with grasses. A good example
of this type of
forest is the cross-timbers area of Texas, Oklahoma,
Kansas, and
Arkansas. You can see examples of this type of growth on
the University
of Arkansas cross-timbers website:
http://www.uark.edu/misc/xtimber/index.html
It seems reasonable to say that what is a forest and
what is not depends
on the environmental conditions. There is a spectrum
between dense tree
population in wet areas, to more open savannah forests.
Therefore under
the extreme conditions found in the arid areas of the
southwest and
western United States, a sparsely populated community of
woody plants
should be considered a “forest.”
There is little debate about whether these
representative trees are old
or not. Their “forest” for the most part is
relatively undisturbed by
human activities- they haven’t been timbered or
cultivated. So these
forests should meet even the most strict definitions of
an “old growth
forest” if you accept the first two propositions that
these are trees
and constitute a forest. An important side issue is how do you measure these
trees, since many of
them do not reach breast height? At what point should
their
circumference be measured? As for height, I would think
the “pole
method” would be most appropriate.
Ed Frank
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|
| RE:
Ancient Forests of the Northeast |
Edward
Frank |
|
Sep
26, 2004 18:25 PDT |
Bob,
Your comment about differences of opinion over what to
include as old
growth is interesting as it comes in a time when I am
again struggling
on how to deal with the concept of old growth as I work
on a website.
You seemed to like Lee's pragmatic definition "For
Lee's purposes, it is
whatever the group he is working with says it is."
That works fine if you are dealing with people with a
vested interest in
one definition or another. For people like myself who
are exploring the
concept of old growth forest it is pretty useless. Some definition
or
boundary is needed in order to compare what we see to
the definition. A
classification system allows you to make comparisons. It
allows you to
disagree with the boundaries. It allows you to form
alternative
classifications.
I have read that the Inuit people have about a zillion
different names
for snow. I believe that by giving these variations of
snow different
names and different definitions, it allows them to think
about the idea
of snow in an entirely different level than those of us
who simply call
all of the white stuff snow.
I guess after having read a large amount of material on
the subject a
workable definition for me and from my perspective is
still
unformulated. I would tend to a relatively broad
definition - I am an
inclusionist by nature. I feel that too restrictive of a
definition
limits your conceptualization of issues and processes.
By having a
limited definition, perhaps you think you are making a
stricter
definition and weeding out the gray areas, but what you
really are doing
is leaving out transitional phases which may be your key
to
understanding. I have a broad definition of what are
karst areas and
processes as well, so a broad inclusive definition of
old growth fits in
well.
Ed Frank
Robert Leverett wrote:
| |
Bruce
and I differed on what to include as old growth.
I applied a
more conservative criteria than did Bruce. He
prevailed, though, and
probably for the right reasons, given the
readership at which we were
aiming. All in all, the partnership was a solid
one. We worked well
together and it is appropriate that Bruce's name
is listed first. He did
a heck of a job.
Bob
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|
|
| RE:
Ancient Forests of the Northeast/Old Growth |
Edward
Frank |
|
Sep
26, 2004 18:37 PDT |
Bob and other ENTS,
This is my introduction on Old Growth from the ENTS
website. Some of you
may have seen it, but it seemed to fit with the last
post.
The Minnesota Department of Natural Resources
http://www.dnr.state.mn.us/forests/oldgrowth/index.html defines
old growth
as follows: "Old-growth forests are natural forests
that have developed
over a long period of time, generally at least 120 years
(DNR definition
and consistent with definitions for the eastern United
States), without
experiencing severe, stand-replacing disturbance--a
fire, windstorm, or
logging. Old-growth forests may be dominated by species
such as sugar
maple, white spruce, or white cedar that are capable of
reproducing under a
shaded canopy. These old-growth forests can persist
indefinitely. Old-growth forest may also be dominated by species such
as red pine, white
pine, or red oak that do not reproduce as well under
shade and that require
disturbance to open the canopy. These old-growth forests
will eventually be
replaced by the more shade tolerant tree species in the
absence of
disturbance."
The attempt to define old growth is a mire of different
viewpoints,
perspectives, motivations, terminology. At this time I
don't think a
simple all-encompassing definition exists as the
characteristics of an old
growth forest varies from locality to locality and from
forest type to
forest type. Maurice Schwartz found ninety-eight
separate definitions of
old growth with an internet search. The above definition
has problems
itself. Some forest types are dominated by trees with a
lifespan of less
than 120 years. These forests otherwise may have all of
the characteristics
of old growth but are excluded by the time criteria
stated above. The
definition is also ambiguous with respect to how much
disturbance is severe
disturbance. Regulators want a strict definition that
can be applied
without compromise, dynamicists want a definition based
upon processes that
are taking place in the evolution of the forest,
environmentalists want a
more encompassing definition to include areas peripheral
to the oldest
forest which are essential to maintaining ecosystem
integrity, lumbering
interests want a limited definition that says that very
little forest is
old growth because of potential public opposition to
timbering old growth
forest.
|
|
| Re:
Ancient Forests of the Northeast |
Don
Bertolette |
| Sep
26, 2004 19:21 PDT |
Ed-
An often quoted "Forestry is not Rocket Science,
it's much more complex than that", comes to mind.
When Bob first started, it seemed possible to come up
with a definition for the piece of New England he was
looking at. As his horizons expanded, the complexity of
defining "old-growth" expanded "LOGarithmically"!
Even
regional definitions become complex (geographic
boundaries, ecosystem boundaries, or?). I'm not
sure I'm correctly citing (jump in here, Lee) the paper
that is coming to mind (a terrible thing to waste!), but
the role of disturbance timing and disturbance severity
threshold are critical to "old-growth succesional
pathways".
Check:
Frelich, L.E. & P.B. Reich. 1995b. Neighborhood
effects, disturbance, and succession in forests of the
western Great Lakes Region. Ecoscience 2:148-158.
for additional thoughts on what needs to be considered
in "defining old-growth". A rather
comprehensive treatment can also be found at
DEFINITIONS OF OLD GROWTH, PRISTINE, CLIMAX, ANCIENT
FORESTS, DEGRADATION, DESERTIFICATION, FOREST
FRAGMENTATION, AND SIMILAR TERMS.
(DEFINITIONS OF FOREST STATE, STAGE, AND ORIGIN)
H. Gyde Lund
Forest Information Services
Email: gyde@comcast.net
I think you might have been looking for convergence, but
it has not yet been known to happen...;>}
-DonB
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|
| RE:
Ancient Forests of the Northeast |
djluth-@pennswoods.net |
| Sep
27, 2004 07:10 PDT |
|
| RE:
Ancient Forests of the Northeast |
Edward
Frank |
| Sep
27, 2004 11:50 PDT |
Dale,
Thanks for the link. One passage in particular stands
out in the description.
"Finally, it is also important to include
representatives of different
ecosystems in old growth, not only the typical
hemlock-white pine or
hemlock-beech associations of the well-known Cook Forest
and Heart's
Content. It is for those reasons that places are
included in this tour such
as Bear Meadows (a large ancient bog) and Cranberry
Swamp, giving visitors
a broader vision of the varied components of the entire
macro-system. While
it is true sometimes that "we can't see the forest
for the trees," it is
just as true that we should not confuse the forest with
the trees. In other
words, while we speak of old-growth forests in terms of
the major tree
species found there, old-growth is really a term
describing entire
ecosystems. The other plants and animals who live within
the tree-defined
framework are vital to the whole."
|
|
| Re:
Ancient Forests of the Northeast |
Don
Bertolette |
| Sep
27, 2004 18:43 PDT |
Ed-
I too have found that "old-growth" is a better
adjective for forest,
forested ecosystem, than it is a direct object...
-Don
|
| Re:
Ancient Forests of the Northeast |
Lee
E. Frelich |
| Sep
30, 2004 06:14 PDT |
Don, and Ed:
There is not and never will be a biological definition
of old growth. Since old growth is a human construct, it
is what people say it is, and that varies among
political jurisdictions.
However, if you want a simple inclusive definition for
outlining forests on the ground for preservation, then
use primary forests (forests that have not been logged).
There is still some subjectivity here, since in some
regions all forests had at least some selective cutting,
and you still have to come up with a subjective
criterion for amount of human disturbance that
disqualifies a stand from the category of primary
forest. Also, primary forest includes a stands dominated
by young early successional forest, old early
successional forest, young late successional forest, and
old late successional forest (the latter is what most
people are stuck on when they discuss old growth).
See the discussion in chapter 5 of my book and in this
paper:
Frelich and Reich, 2003, Perspectives on development of
definitions and values related to old-growth forests.
Environmental Reviews 11: s9-s22.
I have a pdf of the paper I can send to anyone who is
interested.
Lee
|
| RE:
Old Growth Definitions |
Edward
Frank |
| Oct
01, 2004 19:33 PDT |
Lee,
I read your paper and it is very well done. I do
understand what you are saying in the paper. My quandary
is that I would like to have a page or section on the
websites dealing with the concept of "Old
Growth." This
phrase is always being tossed around by this group or
that agency and is in the consciousness of the general
public. A person who comes across a patch of old trees
while hiking will wonder if it is some of the "Old
Growth" he has heard about and what that means. If
someone finds our websites through an Internet search of
"old growth," will we have an explanation
presented there that will be satisfactory to them? Will
we have an explanation that is comprehensible to them?
Will the explanation presented turn on a light
bulb in there head - and say "aH! Ha! I
understand". I have read much of the stuff on the
web defining the term. It is indeed a political
question, it most assuredly depends on tree types
involved, climate, and an entire horde of considerations
couching any proposed definition. I want to have
definition on a web page that is easily understandable
to start with, then go into greater detail of how under
various circumstances other factors must also be
considered.
I do like your explanation of "Primary Forest"
in the paper and that may indeed be the way to go for
the website. I will need to think about things for
awhile, figure out what good concepts are in each of the
various "definitions" and come up with
something. I am particularly intrigued by the definition
from the PA DNR that talks about old growth as an
ecological system that may include bog settings and
other non-forest or perhaps I should say non-typical
forest settings. I think that the dwarfed trees and
other desert plants scattered about arid southwestern
terrains should be considered as "old growth
system" if not actually a forest.
Anyway thanks for sending the pdf file.
Ed Frank |
| RE:
Old Growth Definitions |
Ernie
Ostuno |
| Oct
01, 2004 20:15 PDT |
I always wondered about forests that were affected by
natural disturbance. A case in point: Say there is an
area of old growth that is struck by a windstorm and
suffers an extensive blowdown. Is the acreage that was
affected no longer considered "old growth"
even though it is still part of the larger ecosystem
that does include some surrounding old growth? Another
case: What if the percentage of trees lost was 25,
50 or 75 percent? Is the area that suffered 25 percent
loss of trees still considered old growth while the area
that lost 75 percent no longer considered old growth?
I
don't know if you've seen this before, but it's a
dissertation by one of the Marc Abram's grad students at
Penn State concerning some recent work on
dendroecological studies of forest disturbance
histories:
http://etda.libraries.psu.edu/theses/approved/WorldWideFiles/ETD-396/etd.pdf
Ernie
|
| RE:
Old Growth Definitions |
Lee
Frelich |
| Oct
02, 2004 16:28 PDT |
Ernie:
The old-growth forest that blows down, whether 25%, 50%,
or all of it, is still primary forest and has the
potential to recover to a developmental stage with large
old trees. Since all forests are created by disturbance,
this is part of the natural cycle. The most important
function of reserved old-growth forests is to see how
they respond to and recover from disturbance.
Regarding what to call partially disturbed forests (and
all old-growth stands repeatedly experience partial
disturbance and recovery from it), there are a number of
terms such as mature-sapling mosaic, young forest with
mature remnants, multi-aged pole forests, etc. The
threshold for calling a blowdown a stand initiation
event is subjective, some people say 75% and others 90%
blow down.
These disturbance dynamics are why I think we should be
talking about primary forest rather than old growth
(which is just one stage of a cycle), although old
growth is so well established in peoples minds that we
have to continue to deal with it.
Lee
|
| RE:
Old Growth Definitions |
Gary
A. Beluzo |
| Oct
03, 2004 06:37 PDT |
Lee:
Clearly stated. I agree wholeheartedly with the
language, the challenge is to refocus the debate over
natural forests to "primary" rather than
"old growth", which is simply a snapshot in
the life of the primary (and autopoietic) forest. The
danger in continuing to focus on "old growth
forests" is that as these forests undergo natural
disturbance policymakers could legally (and quite
logically) take them out of protection. I am still very
interested in coming up with a scale of
"naturalness" to apply to forests so that in
New England and elsewhere folks can catalog forest lands
that have had some degree of anthropogenic disturbance
on a continuum.
How do we refocus the policymakers?
Gary
|
| RE:
Old Growth Definitions |
Edward
Frank |
| Oct
03, 2004 23:16 PDT |
Lee, Gary, Ernie, Bob, and other ENTS,
The concept of primary forest is a fine concept and
should be used for regulatory purposes. What I see as a
challenge is how to apply the concept in a manner that
it appeals to the general public? People are impressed
by individual or groups of BIG trees or an individual or
grove of OLD trees. I do not think they are for the most
part impressed or even more than peripherally cognizant
of the dynamic processes of forest renewal.
Intellectually I can appreciate these processes, but I
do not get the same emotional charge for young primary
forest as I do for big trees or old trees. Can the
average person even tell the difference between a forest
that is a primary forest being regrown after a blowdown
from one that is being regrown from a clearcut? Sure
many of you can, if you study forests or are
particularly familiar with the characteristics of forest
processes, the differences are apparent, but members of
that group are in the minority. The majority of the
public, even those who are outdoors people, hikers,
hunters, etc., are oblivious to the differences. Even
within ENTS, most of the posts focus on the few big
trees in a stand and little on the forest structure as a
whole. Big trees or old trees are where most of the
interests lie. If the general public does not appreciate
the concept of a "young" primary forest
regrowing after a blowdown or fire event, can it be
expected that the regulatory or administrative facets of
government will give them much heed?
I was up to Kinzua Bridge State Park, PA today. A year
and a couple months ago at the park, a historic railroad
bridge 201 feet high, across a stream valley, was blown
down by what the weather service determined was a
tornado. A large number of trees were flattened along
with the bridge. They lined up like match sticks
all pointing the same was along the valley walls. It
struck me as I visited the park soon after the storm
that visitors were impressed by the destruction of the
bridge, but also talked about the way the trees had been
downed. A year later there was little talk about the
downed trees. Brush had sprouted to cover much of the
damage. In a couple years the missing trees will not
even be considered. The point is after a blowdown
or fire in a Primary forest of old or big trees, people
will be interested in the destruction immediately
afterward, and they may bemoan the loss of the old
forest, but There will be little if any emotional
attachment for the young forest replacing the old one.
It may be primary forest, but is there a drive to
protect it? Or even give it special management
considerations?
Ed Frank
|
| RE:
Old Growth Definitions |
Lee
E. Frelich |
| Oct
04, 2004 05:49 PDT |
Ed:
Most tree populations in the northeastern U.S. that have
not been logged go back 3000-5000 years. That usually
interests most people, especially when you tell them
that the young post-disturbance forest is carrying on a
5000 year heritage.
Lee
|
| RE:
Old Growth Definitions |
John
Knuerr |
| Oct
04, 2004 05:24 PDT |
J. Baird Callicott, a philosophy professor, wrote an
essay entitled "The Land Aesthetic", in which
he tries to capture Aldo Leopold's thoughts on how we
come to appreciate the landscape.
In brief:
- he begins by pointing out that the Western
appreciation of natural beauty does not flow naturally
from nature itself; is not directly oriented to nature
on nature's own terms; nor is it well informed by the
ecological and evolutionary dynamics. it is superficial
and narcissistic; in a word, it is trivial. He
describes Leopold's land aesthetic as an appreciation
that begins simply with our ability to perceive what is
pretty. To develop a land aesthetic requires a
willingness to learn things about the land that deepens
our knowledge which in turn informs our
senses.
I'm
pretty sure that all of us on this list have experienced
this process personally. The challenges you point
out are not limited to the issue of forest appreciation.
The greater issue is the overall dumbing down that is
occurring in our culture and the fact that most people
are more and more cut-off from significant experiences
of the natural world around them. And, the expectation
is that the natural world will give them wow-experiences
that they can immediately consume (sound-byte
mentality). So, I'm thinking if we can give them
an immersion experience in the forest that includes a
cognitive component on forest dynamics, we might have a
shot? The language we use doesn't need to be complex. It
could be in the form of a story (... imagine your
standing in this spot 140 years ago... what would
you see?) that engages them and educates them.
Any thoughts?
|
| RE:
Old Growth Definitions |
Robert
Leverett |
| Oct
04, 2004 05:47 PDT |
John:
You've adroitly opened a whole new area of exploration
for us on the list that we've heretofore hardly touched
upon. I have a deep stack of Wild Earth Journals with
musings on the meaning of wilderness, wilderness
experience, and a string of hot debates between J. Baird
Callicott and Dave Foreman. The two started out amiable
enough but grew ever more strident with one another.
Both have substantial egos, BTW, but I think that
overall Callicott wins in the size of ego
department. He often seems to know better what
significant thinkers of the past were thinking than did
the thinkers themselves. I guess I better dust off my
copies of Wild Earth.
What we are aiming toward is an
exploration of the complex mix of science, ethics,
aesthetics, politics, recreation, etc. in attempting to
discern the purposes and roles of wilderness and its old
growth surrogate. I'm sure my buddy Don Bertolette will
have lots to say on the subject. Anyway, thanks, for
broaching the topic. A great one.
Bob
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