[APWG] NEWS: Conservation Strategies Must Shift with Global Environmental Change

Fri Mar 7 07:11:28 CST 2008

Bob, one problem with your C4 thesis is that we have C4 native 
species too.  They behave in ecosystems as if they were a part of the 
natural evolution of that system, which of course they were.  I have 
not seen evidence that the native warm-season grasses, for instance, 
have begun to to be invasive problems in response to elevated CO2.

At 04:10 PM 2/4/2008, Bob Beyfuss wrote:
>Hi Bill
>Thanks for posting. These issues are worthy of discussion.
>
>As long as there is international contact between nations there will 
>be introductions of pests, diseases and plants that affect native 
>plants and animals and alter currently existing ecosystems 
>regardless of how diligent we try to be to avoid them and I am not 
>saying we should not be diligent in this regard.  There is nothing 
>wrong in trying to preserve the ecosystems and the plants that we 
>currently enjoy. I guess I question some of the means we are 
>using.  Our annual flu outbreaks, which kill many people, are a good 
>example of an annual unwanted and unintended "invasive" pathogen 
>introduction. We could probably save many lives each year by simply 
>not letting anyone into or out of this country.  It is naive to 
>think that we can isolate ourselves or our current ecosystems to 
>become completely immune to the potential biological threats from 
>the rest of the world given the fact that we are a global society.
>
>The question is "What do we do about this situation?"
>
>It seems that one of the politically correct approaches in the case 
>of plants is to label them with value laden, emotional terms like 
>"alien, exotic, invaders" and kill them using whatever methods we 
>want without really knowing the long term consequences of our 
>actions or bothering to investigate what the long term consequences 
>of the "invasions" may be. It is much easier to justify killing 
>things once they have been sufficiently demonized by rhetoric such 
>as this. "Wars" are difficult to support without mustering 
>appropriate propaganda.
>
>Certain plants labelled as invasive are what are known as C4 plants 
>because they utilize carbon dioxide differently and much more 
>efficiently than C3 plants. This certainly gives them an edge in 
>this globally changed climate with double the Co2. Couple this with 
>human disturbance as pointed out by Craig in the original post on 
>Yellow Star Thistle that started this dialogue and you start to see 
>the root of the problem.
>Craig wrote,
>"The article states that "It pushes out native plants", but we have 
>measured just the opposite interaction between the YST and 
>natives.YST only grows well, wherever the native understory has been 
>completely removed, like it has in 99% of lower elevation 
>California.  Wherever you have a good density of native plant 
>understory, the YST is never any problem"
>
>  So is YST the problem or is it the removal of the native understory?

ST is now the problem because it reduces drastically the biodiversity 
of an ecosystem.  Getting native species back into the site is the 
answer to the ecosystem biodiversity problem.  It appears that at 
least part of the answer to getting native species back in is 
controlling the YST (or saltcedar or cogongrass).

What is your take on the value of biodiversity in natural 
ecosystems?  We're not talking about food production ecosystems here.

Bill Stringer

>Even a few degrees warmer temperatures has profound effects on any 
>plant species ability to survive. Does anyone not think that the 
>proliferation of Zone 6 plants (USDA hardiness Zones) in Zone 5 is 
>not related to climate change? The link between climate change 
>(higher Co2 and temperatures) and success of invasive plants is 
>really pretty obvious to most people who understand a little about 
>how plants grow.
>
>Chestnut blight disease reduced the % of American chestnuts in my 
>local forest here by 99% and at one time more than 50% of all the 
>trees growing here locally were American chestnut according to 
>historical records.  The chestnuts were replaced by mostly Sugar 
>maple trees over the past 90 years or so. Is is fair to say that 
>sugar maple "destroyed" the previous chestnut dominated ecosystem? 
>If you can say that "destroy" means the same thing as "alter" or 
>"change" then that is indeed true. Was this a good or bad thing? 
>Well, I guess that depends on whether you favor eating chestnuts or 
>using maple syrup. These are human distinctions, the forest remains 
>as a forest. It will still be a forest even if it becomes dominated 
>by Ailanthus altissima. The sugar maple dominated ecosystem may very 
>well be replaced by an Ailanthus dominated ecosystem but unless it 
>all gets bulldozed, it will remain as a forest ecosystem.
>
>Pathogens such as chestnut blight and pests like the hemlock Wooly 
>adelgid that usually kill their hosts present an evolutionary dead 
>end to themselves. We are already seeing American chestnut seedlings 
>growing back in some areas as well as some resistance to the hemlock 
>wooly adelgid. If a completely blight resistant strain of chestnut 
>is discovered should we clear cut all the sugar maple trees and 
>plant back the chestnuts in the name of restoration ecology?
>
>Western hemlock has evolved resistance to the "invasive" adelgid 
>pest on the west coast because the pest has been there for a long 
>time. In the 1980's NY State spent huge sums of money trying to 
>first quarantine and eradicate an imported pathogen called 
>Scleroderris canker. I still have filing cabinets full of bulletins 
>on how to eradicate this disease which turned out not to be a 
>serious problem after all. How many millions and millions of dollars 
>have been spent trying to eradicate gypsy moths?
>
>In retrospect, most will agree that these and many other specific 
>attempts to kill off the bad guys have resulted in huge wastes of 
>money and resources. I contend that 50 years from now most of our 
>current war on invasives will be similarly judged.
>
>
>
>
>
>  At 01:09 PM 2/4/2008, Bill Stringer wrote:
>>At 11:41 AM 2/1/2008, Bob Beyfuss wrote:
>>>This is the best article I have ever seen cited on this list serve. People
>>>need to wake up the the fact that virtually every ecosystem on this planet
>>>is now dramatically different than it was even 50 years ago due to human
>>>activity on a global scale.
>>
>>>Efforts to "restore" ecosystems that have been
>>>altered by irreversible global changes, such as doubling the carbon dioxide
>>>levels in the atmosphere and rising temperatures, are a huge waste of money
>>>and resources. Invasive plants are just one of the many symptoms of these
>>>changes -
>>
>>>Invasive plants are clearly a symptom of our willingness to import 
>>>exotic organisms.
>>>I'm not so sure of the link between invasive plants and global 
>>>climate changes.
>>
>>There's anthropogenic greenhouse gas increases, and then there's 
>>introduction of
>><http://www.cogongrass.org/>cogongrass , 
>><http://www.nps.gov/ALIEN/fact/tama1.htm>saltcedar , and numerous 
>>other examples.  These are different problems,
>>and should not be lumped together under "huge waste of money and 
>>resources" .
>>
>>
>>>yet we declare "war" on alien, exotic, species that "menace" us as
>>>though killing off these plants will somehow solve the problem.
>>
>>Which problem, Bob, the Great Greenhouse, or Exotic invasive plants that are
>>documented to be destroying native ecosystems, and throwing  the 
>>bio-geo-chemistry
>>out of whack.
>>
>>
>>Tell that to American chesnut, and hemlocks.
>>
>>Thanx
>>
>>Bill Stringer
>>
>>
>>>At 10:06 AM 2/1/2008, Olivia Kwong wrote:
>>> > http://www.sciencedaily.com/releases/2008/01/080131101747.htm
>>> >
>>> >Conservation Strategies Must Shift With Global Environmental Change,
>>> >Ecologists Urge
>>> >
>>> >ScienceDaily (Jan. 31, 2008) . Traditional ecosystems in which communities
>>> >of plants and animals have co-evolved and are interdependent are
>>> >increasingly rare, due to human-induced ecosystem changes. As a result,
>>> >historical assessments of ecosystem health are often inaccurate.
>>> >Scientists are now suggesting that efforts should focus less on restoring
>>> >ecosystems to their original state and more on sustaining new, healthy
>>> >ecosystems that are resilient to further environmental change. Accepting
>>> >some permanent changes may increase health of ecosystems.
>>> >
>>> >See the link above for the full article text.
>>> >
>>> >
>>> >_______________________________________________
>>> >PCA's Alien Plant Working Group mailing list
>>> >APWG at lists.plantconservation.org
>>> > 
>>> http://lists.plantconservation.org/mailman/listinfo/apwg_lists.plantconservation.org 
>>>
>>> >
>>> >Disclaimer
>>> >Any requests, advice or opinions posted to this list reflect ONLY the
>>> >opinion of the individual posting the message.
>>>
>>>
>>>
>>>_______________________________________________
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>>>APWG at lists.plantconservation.org
>>>http://lists.plantconservation.org/mailman/listinfo/apwg_lists.plantconservation.org 
>>>
>>>
>>>Disclaimer
>>>Any requests, advice or opinions posted to this list reflect ONLY 
>>>the opinion of the individual posting the message.
>>
>>Bill Stringer
>>Editor, Journal of the SC Native Plant Society
>>PO Box 491
>>Norris, SC 29667
>>
>>864 656 3527
>>
>>www.scnps.org
>
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>
>Disclaimer
>Any requests, advice or opinions posted to this list reflect ONLY 
>the opinion of the individual posting the message.
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