[RWG] Ecosystem Restoration Collapse

[Katie Fite]

Wayne,

I am interested in the discussion.

And discussions of what ecological restoration is, and also discussions of
how the term "restoration" is currently being used by agencies or at times
industry  -  to describe imposing major disturbances on mature or old
growth woody vegetation communities  - with such disturbances often then
leading to weed invasions.

Katie Fite

On Sat, Feb 25, 2012 at 8:33 PM, Wayne Tyson <landrest at cox.net> wrote:

> **
> All:
>
> One of my fellow subscribers has been corresponding with me off-list the
> subject of ecosystem restoration standards, and I have been unsuccessful in
> persuading the subscriber to keep the discussion on-list, as I believe the
> subject is of broad common interest. This person apparently believes that I
> am the only one (with one or two others) interested, because no one else
> has weighed in on the subject. Is this person right? Are none but three or
> four of us interested in this topic? Should this and related topics be kept
> off list (to keep topics of restricted interest from clogging the
> in-baskets of the majority? If so, how many subscribers are there to APWG
> and RWG?
>
> I am hereby taking the liberty to broach the most recent topic, the
> collapse of ecosystem restoration projects, signified by the return of weed
> dominance in some cases. I would add to this that ecosystem restoration
> projects also "collapse" or fail to "take" whether or not weeds dominate. The
> off-list poster confined the comments to grasslands, so I will primarily
> address that issue, but the same principles hold true for other biomes and
> can be more broadly applied.
>
> *First, the "return" of grassland restoration projects to weed-dominance.*
>
> There are a number of reasons for this, some related to context issues
> like soil type, some related to restoration methods, but consideration of
> soil type must be part of the restoration assessment, planning, and
> execution process. Soil type is important; in the case of grassland
> restoration, it is preferable (actually essential) that a grassland soil is
> present--if it isn't, all the King of Restoration's horses and all the
> KoR's men and women will not be able to make a silk purse out of a sow's
> ear (without some major alterations to the soil). I invite others to expand
> and expound on this subject; I will mention only some factors.
>
> True grassland soils tend to have identifiable characteristics. They tend
> to develop on alluvial or aeolian soils of finer texture and containing
> considerable natural humus and soil flora/fauna, as well as mineral
> deposits at depth (commonly at or near the effective bottom of the root
> zone) such as calcium and sodium. Disturbance of such soils can render the
> site largely incapable of supporting a true grassland, such as when
> bulldozed or otherwise excavated and the surface is changed from a
> grassland-type soil to a jumbled mass, sometimes consisting of coarse
> B-horizon or deeper deposits unsuited to grassland development. This should
> be determined in the initial assessment and feasibility investigation, and
> consideration should be given to restoring an ecosystem/plant community
> type other than grasslands, at least as a transitional measure until
> something resembling a grassland soil can be developed. (Wholesale
> replacement of the degraded soil with grassland soil can be done, but it is
> terribly expensive.)
>
> If one tries to establish a grassland on non-grassland soils, one is most
> likely going to be disappointed, and "failure" is almost foreordained. I
> have, however, attempted to grow hair on such billiard-ball sites, with
> limited success. If other conditions are favorable, a soil can sometimes be
> developed (or its development accelerated) by certain tricks (e.g., praying
> for gopher or prairie-dog invasions, adding mycorrhizal fungi and other
> essential soil organisms, and transitional plantings of annual
> plants--sometimes even grasses, but more commonly dicots like weeds and
> flowers that will be humus-builders. Short-lived perennial plants, even
> some shrubs, also can be used. This approach is much cheaper than soil
> importation, and sometimes can be better. The actual strategy should fit
> the context.
>
> I should make it clear that my first fifteen years of attempting ecosystem
> restoration projects were all failures by my own standards, and I have
> continued to make some mistakes once ever since. One must, I believe, learn
> from actual experience. However, just experience is no guarantee of
> expertise. If I had stubbornly held on to what I "knew" and refused to
> consider that what I knew might be wrong, I would have continued to fail. I
> did get to the point that could reliably initiate ecosystem processes and
> avoid "collapse." All restoration practitioners can do is to accelerate
> ecosystem development anyway, largely by setting up conditions that will
> permit or even maybe encourage natural ecosystems processes to work. We
> don't actually restore living systems.
>
> In short, most failures can be traced back to the kind of work done and
> not done to set up favorable conditions for natural forces to work upon.
>
> In short, two of my biggest mistakes (there have been many others) have
> been to:
>
> a. fail to properly assess site conditions and develop a restoration
> program that modifies or matches those conditions.
>
> b. plant too many seeds and plants, spending far too much money and doing
> far too much presumptuous guesswork.
>
> If a grassland soil is present, indigenous species can persist and
> eventually re-assert dominance over weed populations. If one can mimic
> grassland soils, one has a chance of fostering the development of
> grassland, but one must out-draw the Lone Ranger to do it. If one is
> presumptuous enough to believe that all that needs to be done is to kill
> weeds and scatter seeds, collapse, unless one is terribly lucky, is rather
> more likely than not.
>
> Disturbed sites (from bulldozing to trampling) tend to favor weeds. They
> are the scabs, as it were, on the scarred face of the earth--not pretty,
> but an inevitable result of land mismanagement.
>
>
> *2. Collapse of "restored" ecosystems that do not necessarily result in
> dominance of weeds.*
>
> This phenomenon is often the result of simply seeding or planting too many
> and/or the wrong balance of the right (and/or wrong) species at the wrong
> time, possibly including "maintenance."
>
> This can be the subject of another discussion, but I have run out of time
> . . . (and since it does not include weeds so much, it might be
> "inappropriate" for these lists.
>
> WT
>
>
>
>
>
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>
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