Degenerate Old Growth

Degenerate Old Growth

Mike, Joe, others,

What exactly is a "degenerate old-growth stand" according to these definitions?

Ed

"I am not bound to please thee with my answers."
William Shakespeare

----- Original Message -----
From: Mike Leonard
To: entstrees@googlegroups.com
Sent: Tuesday, January 22, 2008 7:01 PM
Subject: [ENTS] Re: Clearcutting Massachusetts Public Lands

Chris,

The state is using the so called shortage of early successional grassland/forestland as an excuse to clearcut.

Speaking of Orwellian language, how about the term "one cut shelterwood"?

This term is applied to those stands that have ample advanced regeneration that was started by accident or without deliberate effort to establish it. In the "Practice of Silviculture" by Smith, Larson, Kelty, and Ashton, they say it is useful for "rehabilitating" many kinds of degenerate old-growth stands or stands that have been high-graded.

Sorry profs, it's still a clearcut to me.

Mike

== 2 of 3 ==
Date: Tues, Jan 22 2008 5:14 pm
From: "Mike Leonard"

Ed,

I couldn't find an official forestry definition in the text but I think
it refers to old forest stands that are starting to break up because
most of the dominants have reached or are past biological maturity and
are in a general state of decline. The term might apply better to
shorter lived species like balsam fir rather than mixed forests where
species decline at different ages.
So if you are only interested in producing wood fiber, then it might
make sense to some to wipe out the overstory and start again.
It reminds of some of my forestry professors at UMass who were furious
that any part of the Adirondacks could be set aside as wilderness or old
growth reserves. They thought it was a huge waste of a forest resource
that should be exploited. And they also told us that we would never get
forestry jobs unless we joined SAF.

Mike

== 3 of 3 ==
Date: Tues, Jan 22 2008 10:29 pm
From: DON BERTOLETTE

Ed-
Without any doublespeak from any origin, it would be old-growth stands that have lost their resilience (ability to respond to disturbances, man-made or natural) and whatever plant community quality the stand WAS characterized by has been sufficiently degraded that even quality restoration efforts might not succeed.
-Don

==============================================================================
TOPIC: Clearcutting Massachusetts Public Lands
http://groups.google.com/group/entstrees/browse_thread/thread/51883e2150cb3a60?hl=en
==============================================================================

== 1 of 4 ==
Date: Fri, Jan 25 2008 1:47 pm
From: "Edward Frank"

Mike and Don,

Thanks for the responses. Don it is still not clear to me what you mean by "lost their resilience." If for example a tornado flattened one of these "degenerate old growth stands" and flattened another stand nearby that was not degenerate, would there be a difference in what grew from the flattened remains? I also do not understand what you mean by "plant community quality" Since the species in a stand tend to change over time, how is the "plant community quality" change differentiated from simply changes in species through time?

Ed

== 2 of 4 ==
Date: Fri, Jan 25 2008 4:30 pm
From: DON BERTOLETTE

Ed-
You know, you're asking better and better questions! I'll do my best to answer them, in the body of your text below, IN SMALL CAPS...:>}

From: edfrank@comcast.netTo: entstrees@googlegroups.comSubject: [ENTS] Re: Clearcutting Massachusetts Public LandsDate: Fri, 25 Jan 2008 16:47:48 -0500

Mike and Don,

Thanks for the responses. Don it is still not clear to me what you mean by "lost their resilience.

" IN GENERAL, AND IN THIS CONTEXT, RESILIENCE IS CONSIDERED TO BE THE AMOUNT OF DISTURBANCE THAT AN 'OLD-GROWTH ECOSYSTEM' (I'D SAY AUTOPOETIC IF I COULD SPELL IT ) CAN SUSTAIN, AND RETAIN THE EXISTING PLANT COMMUNITY QUALITY...CLEARLY A TORNADO THE LIKES OF THOSE IN THE MIDWEST IS LIKELY TO EXCEED THAT. BUT LET'S SAY IT WAS A MICROBURST THAT JUST TOOK OUT A ONE ACRE STAND...IF IN A REASONABLE PERIOD OF TIME THAT STAND REPLACED ITSELF AND WAS OTHERWISE UNDISTINGUISHABLE FROM THE REST OF THE STAND (AGE DIFFERENCE EXCEPTING), THEN THE ECOSYSTEM HAD SUFFICIENT RESILIENCE (SUFFICIENT STORAGE OF NUTRIENTS, SOURCES OF SOIL MICRO-ORGANISMS, ALL THE "STUFF" THAT IT TAKES TO MAKE AN "OLD-GROWTH ECOSYSTEM") TO SUSTAIN SUCH AN INJURY. OBVIOUSLY, DISTURBANCES COVER A BROAD CONTINUUM AND AFFECT DIFFERENT PARTS OF THE ECOSYSTEM. A TORNADO WHISKING AWAY EVERYTHING FROM SOIL, COARSE WOODY DEBRIS, CROWNS, ETC. OBVIOUSLY WOULD LEAVE AN AREA UNRESTORABLE FOR PERHAPS A CENTURY OR MORE.

If for example a tornado flattened one of these "degenerate old growth stands" and flattened another stand nearby that was not degenerate, would there be a difference in what grew from the flattened remains?

I'D BE MORE COMFORTABLE RELYING ON LEE'S INPUT HERE, BUT MY FIRST STAB WOULD BE CENTERED AROUND HOW MUCH OF THE 'SEED BANK' AND SOIL MICRO-ORGANISMS WERE LEFT BY THE TORNADO...IF UNTOUCHED, THE SEED BANK/SOIL BASE WOULD BE A STRONG DETERMINANT IN WHAT EVOLVED AT THESE SITES..

I also do not understand what you mean by "plant community quality"

IT'S A TERM I MADE UP TRYING TO EXPRESS MY THOUGHTS WITHOUT PLACING SOCIAL, POLITICAL, OR ECONOMIC VALUES....BASICALLY IT'S "ALL THE "STUFF" THAT IT TAKES TO MAKE AN "OLD-GROWTH ECOSYSTEM"

Since the species in a stand tend to change over time, how is the "plant community quality" change differentiated from simply changes in species through time?

YOU'VE JUST ABOUT STEPPED INTO A MUCH LARGER TOPIC...STAYING CLOSE BY, MY RESPONSE IS GIVEN SIMILAR CYCLIC INPUT, THAT STAND WILL EVENTUALLY CREATE A SEED BANK AND SOIL ORGANISM COLLECTION THAT WILL 'TEND' TO REGULATE THE SPECIES THAT ARE MOST SUCCESSFUL/AVAILABLE, ALL OTHER THINGS BEING EQUAL...I'M STOPPING SHORT OF THE WHOLE DISCUSSION OF 'CLIMAX SPECIES' AND SERAL CLIMAXES (THEY STILL WORK FOR ME, AND I'M HAPPY TO STEP ASIDE AND LET OTHERS ARTICULATE THE THEORIES/CONSTRUCTS/IDEAS ON WHAT REPLACES THE 'CLIMAX' CONCEPTUALIZATION).
-DON

== 4 of 4 ==
Date: Fri, Jan 25 2008 5:09 pm
From: "Edward Frank"

Don,

Say a microburst took out about an acre of forest and it was allowed to regenerate naturally. Would not the initial population of the newly opened area be made up of species that required open sky as opposed to species that regenerate in a closed canopy setting? So they would differ from the surrounding forest for some time until perhaps they were replaced by shade tolerant species.

I don't think tornados in general would destroy the soil structure or microorganism population across the area of effect.

Is there a difference in seed bank available from the degenerate old growth versus a standard old growth forest. Is this suggesting that the degenerate old growth has stopped producing seeds needed to maintain the species?

Ed

==============================================================================
TOPIC: Clearcutting Massachusetts Public Lands
http://groups.google.com/group/entstrees/browse_thread/thread/51883e2150cb3a60?hl=en
==============================================================================

== 1 of 3 ==
Date: Fri, Jan 25 2008 7:12 pm
From: Beth Koebel

Ed,

I would have to agree with your statement, "I don't
think tornados in general would destroy the soil
structure or microorganism population across the area
of effect." The only tornado that might have the
power to do this would be an EF5. If I am wrong about
this I'm sure that Lee(?) and other fellow
meterologists will correct me.

Beth

P.S. EF5 = enhanced fujita scale level 5 (winds over
200 miles per hour or as stated in "Twister", "the
finger of God".

== 3 of 3 ==
Date: Fri, Jan 25 2008 11:26 pm
From: DON BERTOLETTE

Ed-
Depends on the nature of the disturbance...if there are big root wads tipping up say 50% of the disturbance area (microburst, tornado, hurricane...wind event, in any event)...that bare earth exposure is going to favor certain species (those are often called pioneer species)...the 'undisturbed soil mats/forbs/shrubs/epiphytes/etc.' will prevent pioneering species from accessing bare soil...and other species would be favored.
Now in the case we started off on, a one acre disturbed site, that is a space 207' by 207' plus or minus a few tenths. In a tall forest, that's not very big, and depending on topography (aspect, elevation, slope), it may not get enough sun to favor pioneering species...it may favor more shade tolerant species.The patchwork quilt that emerges as these "tree gaps" get filled in with 'favored species', creates a horizontal mosaic, both visually and structurally...these are two features that go along way towards defining an old-growth ecosystem, for me.
As to the damage a tornado does, hey I have no idea outside of what I see on TV...never been near one...I'm just setting up hypothetical scenarios. You tell me what a tornado does to soil and seed banks and I'll be better informed.As to the seed bank comparison, in a general way I'd say there would be a difference in seed viability based on different ages of the most recent seed 'deposits'...the degenerate o-g forest would have older seed, and whatever recent seed it had deposited would reflect the vigor of the remaining species (degenerating to me, means that there's been a reduction in species richness), effectively reducing site bio-diversity.
Am I helping or taking you further away from understanding? There are many on the forum better suited than I in providing more knowledgeable answers!
-Don

==============================================================================
TOPIC: Clearcutting Massachusetts Public Lands
http://groups.google.com/group/entstrees/browse_thread/thread/51883e2150cb3a60?hl=en
==============================================================================

== 1 of 4 ==
Date: Sat, Jan 26 2008 3:01 am
From: "Edward Frank"

Don,

No you are helping me with the concepts. You have explained that degenerate means a loss of species richness in the post below, that serves to clarify what you were saying. Why do these forests lose diversity? I can see loss of tree species in a small patch - like an island of forest in a sea of fields with no seed source to replace lost individuals. Otherwise I need to think about how species richness being lost, encroachment of other species at the field-tree interface etc. What natural processes would lead to species loss in the middle of a larger patch of forest causing it to become depauperate? One might be loss of certain species by disease or insect infestation...

Ed

"I am not bound to please thee with my answers."
William Shakespeare

== 2 of 4 ==
Date: Sat, Jan 26 2008 12:54 pm
From: Lee Frelich

Beth, Ed:

An EF5 tornado can dig a foot or so into the soil, but that is pretty rare
and would only be for very small areas, and it wouldn't destroy the
microorganisms, although it would mix them up a bit, just like tip up mounds.

In most blow down areas in climax old growth forests, the regeneration is
almost the same composition as the canopy that blew down, because the
seedling bank is the same species as the canopy trees, and they are
released from suppression when the big trees die. The seed bank is also
mostly the same species, but a few new seeds might come in--a paper birch
or an aspen, and there might be a few early successional species mixed in,
but you would still call it the same forest type as the one that blew down.
If the forest had not reached climax ( a group of species that usually
replace themselves in the absence of disturbance other than individual tree
death) before the blow down, then the seedling bank would likely be of
later successional species, and the windstorm would push succession
forwards to the climax species group, as was shown for the big blowdown in
the Boundary Waters Canoe Area Wilderness in MN in our recent paper in
Journal of Ecology.

Some of these processes are no being disrupted by the European earthworm
invasion, which really does change the microflora of the soils as well as
the seed bank. Its anyones guess as to how succession will proceed and how
forests will respond to disturbance in the future.

Lee

== 3 of 4 ==
Date: Sat, Jan 26 2008 1:07 pm
From: DON BERTOLETTE

Ed-
It's easy to think in terms of single catastrophic events...kind of like the 'straw man argument'. Old-growth forest ecosystems (OGFE) don't necessarily live forever. Given that, the accumulation of disturbances, large and small, will have a continuum of impacts on an OGFE from negligle to catastrophic. When the OGFE fails to bounce back with full forest vigor, to something like its original self, it could be said by some (not necessarily my word) to be degenerating.

Another way of looking at this is to draw a time line (going from left to right) with non-defined starting and ending points. Over time, an OGFEs response to external stimuli, whether an event that is intense and short, or lengthy and of low intensity (for example, wildfire or climate change), a natural range of variation will develop. These would be lines, more or less parallel to the timeline, the amplitude varying with, say for this discussion, a measure of the health and vigor of the OGFE such as a dendrological analysis of tree growth of all species sizes. Over time, a range of mortality resulting from wildfires could be the disturbance measure.

In the case of SW ponderosa pines, researchers have found that there is an approximate average of 1.9% annual mortality that represents the natural range of variation (NROV) for Grand Canyon NP (GCNP) ponderosa pines extending back to pre-European settlement times and further. When Grand Canyon NP fire managers ignite 'control burns', or for 'allow' wildfires to be used for resource benefit (WFURB), and over the time that the fire managers are performing these activities the measured annual mortality yields 5-10% figures, they are operating outside of the natural range of variation.

THis is in fact the case at GCNP, where fire managers are accelerating the return of fire into the natural fire regime (low intensity fires with high frequency). This acceleration can be represented by a vector (short segment of the timeline) and viewed as successful, or not, by whether it is tending to return to within the NROV, or not.
The goal of this activity is to return the OGFE vector to a point in time where it can once again have its fire regime described as one of high frequency and low intensity. The conditions today reflect a century of fire managements policy (well-meaning as it was) fire suppression. Today we have white firs from the mixed conifer community 'invading' (which would have otherwise been consumed by high frequency, low intensity fires running along the ground) the 'pure ponderosa' forest ecosystem. These white firs, exactly like the kind of tree you'd like for a Christmas tree, really "light up" when ignited by ground fires (usually caused by lightning strikes - GCNP has one of the higher 'ground strike' numbers)...they have lots of volatile chemicals that quickly leap up to consume their crown, and low lying branches of older ponderosa pines...with the current population of competitive young white firs sucking of available nutrients and moisture, the old yellow barked ponderosa pines are stressed, and while their bark at ground level still sustains fairly intense fires, their desicated branches and foliage are much more susceptible to fire...if there is ANY wind, some of the old yellow-barked ponderosa pines' crowns will ignite, torching adjacent trees and then you have a wildfire such as the Outlet Fire in 2000 which went on to burn 15,000 acres before leaving the Park, and into unforested USFS acres where the fire finally went out.

A long long story, but hopefully you stayed with it and picked up what might be described as a degenerating forest...I don't know today, quite where that vector is. I don't know today, whether the OG ponderosa pine FE has the resilience to withstand our fire managers' efforts, AND the anticipated effects of global climate change.
-Don

== 4 of 4 ==
Date: Sat, Jan 26 2008 1:10 pm
From: DON BERTOLETTE

Lee-
Thanks for the clarity that you bring to our discussions!
-

Don

== 2 of 2 ==
Date: Sat, Jan 26 2008 7:31 pm
From: "Ray Weber"

The F4 (still would be EF4 now) that hit Great Barrington,MA in the 1990's
took the forest out entirely, including grass, down to bare ground and dirt.
The rocks under the top grass kind of slowed it down. Most of that was found to be
caused by little "suction vortices", mini funnels that rapidly rotate around the
main funnel. They cause major damage. I documented damage at the end of the tornado's
life to just under a mile wide, including the suction vortices.

Ray

Home