[APWG] Ecosystem restoration Resistance to Invasion the goal for weed management?

[Wayne Tyson]

Dear All:

If things work out as planned, I will have a look at Craig's project sometime in September. 

I, too, would be interested in comparing notes with anyone who has even come close to achieving Craig's performance. While I agree with him in spirit with respect to the high percentages he has achieved, my standards are a bit different--not necessarily better or worse, in my view. My projects were almost exclusively maintenance-free from square one. No irrigation, no fertilizer, no plant "replacement," no maintenance. Self-sufficiency is essential for ecosystem restoration to be complete. I do not object to irrigation, adding plants, or limited "weed control," but my projects had to meet Ewel's criteria, particularly resistance to invasion. (Ewel, J. J. 1987. Restoration is the ultimate test of ecological theory. Pages 31-33 in W. R. Jordan, M. E. Gilpin, and J. D. Aber, editors. Restoration ecology: a synthetic approach to ecological research. Cambridge University Press, Cambridge, UK.). St. John also referenced Ewel in his paper: (St. John, T. V. 1989. Practical application of Ewel's criteria for a successful restoration. Pages 376-380 in H. Glenn Hughes and Thomas M. Bonnicksen, editors. Proceedings of a Symposium: First Annual Meeting of the Society for Ecological Restoration. The Society for Ecological Restoration, Madison, Wisconsin, USA.) 

With respect to weed management, I never did any; I left that up to the healthy ecosystem (resistant to invasion). I must say, too, that I do not object to active weed management when there is a clear trend upward of weed populations. I found that crews, however well-intentioned, did too much damage to the emerging ecosystem to be more useful than damaging--emerging ecosystems are too delicate, even for foot-traffic, which can stimulate weed emergence and growth. Plant additions were not permitted for three to five years. 

I applaud any client who will support any necessary follow-up work, but I never asked for the extra money, thinking it my responsibility to encourage ecosystem restoration as a common practice and an economical alternative to maintained landscapes. The main goal was ultimate effectiveness and a steady trend of improvement (diversity and succession), not the speed of ecosystem development. I do, however, think that very careful sampling of emerging plant and animal populations is ok, and that early indications of success can be determined at that stage. I do not endorse arbitrary time limits and "cover" criteria, as they are irrelevant to ecosystem development. If, for example, "cover" is demanded within 90 days, seedling density will be far too high, resulting in the more aggressive (even indigenous) species suppressing the more slowly-developing ones. Getting the plant density and species proportions right is one of the most demanding aspects of ecosystem restoration practice. 

WT

----- Original Message ----- 
From: "Craig Dremann - Redwood City Seed Company" <Craig at astreet.com>
To: <landrest at cox.net>
Cc: <craig at astreet.com>
Sent: Monday, August 10, 2009 12:13 PM
Subject: Ecosystem restoration, the goal for weed management?


Dear Wayne and All,

Thanks for your reply.  If anyone would like a hard copy of the June 2002
ECOLOGICAL RESTRATION article mailed to you, directly email me your name
and address -- <mailto:craig at astreet.com>

I am thinking about writing a 2009 update to the Shaw article, so anyone
else who has worked on 50 or more acres, and achieved close to 100% weed
management with 100% native understory restored in any wildlands
situation, I would be very interested in comparing notes.

What I have been suggesting recently, is that at all the various annual
wildlands weed meeting around the United States, that the <Shaw Award> be
presented to any weeding or restoration project that gets close to Shaw's
achievement.

In places like lower-elevation California, when you are managing wildlands
weeds, you absolutely must get back to 100% native understory.

I think we will decide in the future, that this must be the goal elsewhere
in North America, because wildland weeds are like a disease in the native
ecosystems, interfering with their function and ability to thrive.

At a minimum the wildland weeds are pirates of space, nutrients and time.

In California from sea level to 5,000 ft. elevation, if you are just
focused on weed management, once you pull one weed, there is always
another hundred weed species to immediately fill in that bare spot that
you made by pulling the first weed, at densities of 40 seedlings per
square inch in some grassland habitats.

Shaw's 74 acres is 5% riparian, 30% native grasslands and 65% oak woodlands.

The FIRST GOAL, needs to be converting the area from weed cover, back to
at least 85% and ideally 100% native cover, using some ecological
restoration technologies that have rapid Performance Standards.

Performance Standards mean, that whatever technique you use, it gets you
close to 99% weed eradication and 99% native cover, within a short amount
of time.

My personal Performance Standard goal in 90 days or less, for central
California native grassland habitats.

The understory of the Shaw property in 1992 was only 1% natives.

The 85% native cover was achieved by 2000, after only three years of
intensive management.  And all of the native plants that grew,  appeared
out of a soil seedbank that was dormant underneath and suppressed by the
exotics, and sprouted once the weeds were managed.

And we are estimating that those dormant native seeds, are at least 35
years old and perhaps as much as 100 years old.

The SECOND GOAL needs to be correcting any missing species, and making
sure you have the correct understory mix that should be within the native
ecosystem, holding it together.

For example, the native clover seeds have a short life span, so dormant
viable seeds did not survive, and Shaw was not able to resurrect them
before their seeds lost viability.   So local populations of native
clovers that exist around the Shaw property need to be collected and
re-inoculated onto the Shaw property.

The THIRD goal, is to manage the native understory, to promote diversity. 
There are certain native species, that once released from the grip of the
exotics, turn into bullies in their own right, and left unmanaged, will
grow as monocultures.

Shaw was not satisfied with just producing a 100% weed-free area with a
100% native cover landscape, but took the next step of managing that 100%
native cover, for species diversity.  Shaw says that managing the natives
for diversity is a much harder task, than just getting rid of 100% of the
weeds.

The two new, undescribed species that appeared from underneath the exotics
on the Shaw property, one is  from the Carrot family--a Sanicula, and the
other from the Sunflower family--a Gnaphalium.

Another field trip--could be a possibility to the Shaw property in
September or October of this year?

Anyone interested, contact me directly, and I will see what can be
arranged, <mailto:craig at astreet.com>.  Please send me you name, address,
phone, email, who you work for, and what weekends would be a possibility
for you to attend in September or October?

Sincerely,  Craig Dremann (650) 325-7333




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