[APWG] Ecosystems Undisturbed Disturbed Restored Re: Tiny test plots set-up, and measure, measure, measure.

[Wayne Tyson]

APWG:

I agree with Craig that it is nearly impossible to find "pristine" 
ecosystems/subsets, particularly in the western US (although islands seem to 
be more susceptible to apparently permanently transformed stands of 
indigenous and alien species, with confirmed cases of extirpation/extinction 
of indigenous species), I have seen at least one example of a Stipa/Nasella 
lepida "meadow" that was apparently alien-free in the midst of a stand of 
chamisal shrubland. It was associated with Dichondra occidentalis as a 
co-dominant forb mixed with indigenous geophytes. It had been penetrated by 
a road, and a site check a few years later revealed that much of it had 
apparently disappeared, and contained alien plants. I suspect that the 
reason for its condition might have been that the chamisal had not been 
penetrated by livestock, though there were undoubtedly other factors 
involved. I didn't do a disciplined survey, but if anyone would like to do a 
serious study of the area, I will be happy to show them the site if it 
hasn't been further "developed." It was owned by a water district at the 
time, so it may still be vegetated.

Despite this, I do hope that Craig is able to restore such areas in a manner 
that will make them permanently resistant to invasion/colonization with 
alien species as self-sufficient ecosystems.

In cases like tarweed-dominated disturbed areas, it may well be that the 
tarweed is not only fulfilling its role as a secondary succession colonizer* 
and acting as a sink for available nutrients, it might be having 
allelopathic effects as well. Craig is quite right that all that is required 
to "restore" such areas is for the restoration ecologist to be a temporary 
propagule vector.

WT

*aka "weed." Alien weeds perform this function in the absence of indigenous 
"weed" populations, and if Craig or anybody can get enough indigenous "weed" 
propagules onto the site and going early enough, the 90 or 100 percent cover 
of indigenous species might be achievable. I hope Craig has found a way to 
produce enough such propagules to do that without adversely affecting 
indigenous stands and their seedbank reserves. After all, terrestrial 
ecosystem restoration mainly consists of accelerating succession and 
short-circuiting colonization by alien species in a way that produces a 
fully self-sufficient and diverse species assemblage that represents the 
ecological potential and the historical or pre-historical "pristine" nature 
of the site.


----- Original Message ----- 
From: "Craig Dremann - Redwood City Seed Company" <Craig at astreet.com>
To: <apwg at lists.plantconservation.org>
Sent: Wednesday, August 19, 2009 8:55 AM
Subject: [APWG] Tiny test plots set-up, and measure, measure, measure.


Dear Tony and All,

When you have an exotic plant, like the cereal rye, it might look like it
is being invasive, like the star thistle on Russian Ridge at
http://www.ecoseeds.com/invent.html

However, when you measure carefully, you find that what looked like an
invasion, was just an exotic moving into a ruin of a former native
ecosystem.

WEED-FREE MATHEMATICAL CONSTANTS - What I am proposing, is that there are
mathematical constants in the native non-riparian understories, where the
proper percentage cover of local natives, are resistant to exotic
invasions.'

We need to have those exact measurements, but finding examples of pristine
densities unmolested by sheep and cattle, may be as difficult as finding a
virgin forest, especially in the arid West, where the pristine examples of
intact understories are rare.

PRISTINE MODELS LEFT IN THE WEST? According to my 1997 Megatransect, I
could not find any pristine examples in South Dakota or southern Idaho,
and Wyoming and California had less than 1% of the areas surveyed, had any
pristine examples.

Nevada and Utah had pristine examples in 6-7% of the area, and Colorado
was the winner at 11%, but that was partly because my transect went over
the alpine. mountain pass between Gunnison and Denver.

Even Yellowstone did not have many pristine areas left, having been grazed
before it was made into a park, with only 4% of its area still with a
pristine understory.

What that means, is we should not pre-judge a new exotic, and immediately
label it as invasive, when it grow into what looks like a native
understory.  Where the proper native plants are gone and not at the proper
densities, then empty niches are opened up for the weeds to grow.

STUDY & MEASURE PRISTINE AREAS - What that also means, is that we need to
study and measure those remaining pristine examples, as models of what
species and what percentage cover, we need to put back in the place of the
exotics.

USE SOME MUCH WHEN SOWING SEEDS - And when we sow native seeds, especially
in the arid West, you need to mix the seed with some kind of mulch, to
cover the seeds.  We used fresh sawdust in the test plots at
http://www.ecoseeds.com/greatbasin.html, because the scent of the sawdust
also hid the seed from rodents.

MUFFIN PAN GRANIVORE TEST -- Also, before you sow your native grass seeds,
you should take a muffin pan, and put a tablespoon of each species of
seeds that you are going to sow into your future test plots, into a
separate muffin depression. Smooth out some bare soil in your future test
plot site and put the muffin pan in the middle of a bare area at least 3
feet in diameter.  Then come back every day or so, and see who comes and
what seeds are eaten/cached first.

HUNGRY GRANIVORES STEALING EVERYTHING? - I saw a test plot sowing project
done in the Mojave desert about a decade ago, that planted tens of
thousands of dollars worth of hand-collected, local native seeds in a
10-acre test plot.  What the Harvester ants had done within a few weeks,
they had dug up every single seed, and piled then into conical piles about
20 feet apart in each direction, , and the ants were in the process of
moving them into their nests to cache them.

TINY TEST PLOT PROCESS - So your Tiny Test plot process, should go as
follows:

1.) Measure the percent cover in your future test plot area, as carefully
as possible.

2.) Measure the percentage cover in a pristine native area nearby, or if
that is not available, a native area where the target weed has not invaded
yet, and pay close attention to the percentage of bare soil and percentage
cover of other exotics.

3.) Collect some local native seeds.  If possible, grow some into
seedlings within the next few months.

4.) Set up your Muffin Pan Granivore test.   If you find that the
granivores are active, retry the test, by mixing the seeds with something
that can help hide them, like fresh sawdust, chili powder, etc.  The other
option, is to sow your Tiny Test plots in the rain, because granivores do
not like wet seeds.

5.) Set up your Tiny Test Plots (TTPs).

6.) Set up your two Ex-situ Test pots, for each species that you sowed in
the TTPs.

7.) See what happens within 90 days or less.  Use you Ex-situ potting-soil
pot to identify the native seedlings, so you can identify what is coming
up in your regular test plots.  You should have zero exotics, and 95%
native cover, within 90 days or less.

8.) Even if you do not have any local native seeds to sow, you should set
up some Tiny Test plots, and do something different that what you have
ever done in the past.

Like for the Cereal rye, I would try some fertilizing experiments, with
different levels of fertilizer, separate from any seed sowing plots.  Or
Tiny Test plots, with just mowing at different heights, like ground level,
1", 2", 3",  4" etc.   Just like Shaw, you might find some native seeds
dormant underneath the cereal rye?

I hope this encourages everyone to go out and set up some Tiny Test Plots
this autumn.

Sincerely,  Craig Dremann (650) 325-7333



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