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<DIV><FONT face=Arial size=2>APWG:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>It is unfortunate that the equestrian folks were
not involved in project planning. Perhaps they were, and perhaps the COE
representative was misquoted when he said that restoration would take place if
natural colonization had not taken place in a couple of years. I may have
thought much the same way many years ago (so hereby hope to correct the error),
but experience has taught me that a quick intervention, if well-thought-out, is
ESSENTIAL if satisfactory results (highly diverse riparian gallery forest
resembling a "climax" association) are to be realized economically. I have
briefly stated the reasons along with the basic approach (yes, the devil is
sometimes in the details) for successful riparian ecosystem restoration below.
Natural colonization can be a PART of a sound ecosystem restoration project, and
always should be, but in cases like this it is asking for big trouble.
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Since Arundo donax apparently does not reproduce by
seed, or if so, very rarely in North America, once it is eradicated, a modest
but regular maintenance effort should minimize reinvasion, particularly if
eradication starts at the top of the watershed. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Restoration by natural colonization is feasible,
but probably not advisable, as the most prolific indigenous species are likely
to form almost "pure" stands of one or a few "pioneer" species (e.g.
Salix lasiolepis in Southern California). To ensure a highly diverse stand as
quickly as possible, the site should be planted with a mix of species indigenous
to riparian sites in the bioclimatic region of the project starting with those
least common (e.g. Salix gooddingii). To avoid excessive colonization by Salix
lasiolepis (don't worry, they will colonize anyway, both vegetatively and
sexually, as will other pioneer species), project grading should be done when
they are not dispersing seeds. Unlike more xeric sites, true riparian areas can
be planted, at least in part at other times, but the fall and winter seasons are
most likely to be the best (although the actual timing should be based on a
carefully worked out set of project requirements). Pole cuttings, rooted and
unrooted or callused, can be planted deeply to provide large trees more quickly
at low cost, but bare-root stock can be grown or purchased for species more
difficult to establish in this way (e.g. Platanus racemosa). </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Southern California riparian systems can be highly
variable, particularly with respect to soil profile and groundwater, so specific
data needs to be collected to optimize results (this is far cheaper than even
spotty failures). Irrigation should not normally be used, except as a supplement
to rainfall and flooding events that do not materialize according to the plan.
However, irrigation of true riparian restoration sites is only justified to save
a significant proportion of the "investment." Any restoration program must
contain reasonably well-founded attrition factor(s). </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Restoration should proceed immediately following
vegetation removal, before colonization by unwanted vegetation. Any delay in
establishing desirable vegetation will make restoration more difficult, costly,
and risk much greater chances of reduced performance or failure. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>You can see a project that was done this way* along
the northerly side of the Temecula Creek channel in southwestern Riverside
County. The project consisted of a 2 1/2 mile reach between Avenidas De Missions
[sic] and Butterfield Stage Road. You can see it from Redhawk Parkway too, and
on Google Maps/Earth, about 2 miles easterly of Interstate 15, just south of
California State Route 79, southeasterly of the town of Temecula. Originally it
was a 100-foot strip on the north side of the channel. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>WT</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>*As is the case with all restoration projects, this
one was not completed entirely in accordance with specifications, but it is
about as good a case of real-world results as can be expected. One unexpected
result: Theft of nearly all of the few California sycamores that were planted.
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>----- Original Message ----- </FONT>
<DIV><FONT face=Arial size=2>From: "Olivia Kwong" <</FONT><A
href="mailto:plant@plantconservation.org"><FONT face=Arial
size=2>plant@plantconservation.org</FONT></A><FONT face=Arial
size=2>></FONT></DIV>
<DIV><FONT face=Arial size=2>To: <</FONT><A
href="mailto:apwg@lists.plantconservation.org"><FONT face=Arial
size=2>apwg@lists.plantconservation.org</FONT></A><FONT face=Arial
size=2>></FONT></DIV>
<DIV><FONT face=Arial size=2>Sent: Friday, August 06, 2010 5:29 AM</FONT></DIV>
<DIV><FONT face=Arial size=2>Subject: [APWG] NEWS: Norco riders reject arundo
removal</FONT></DIV></DIV>
<DIV><FONT face=Arial><BR><FONT size=2></FONT></FONT></DIV><FONT face=Arial
size=2>> </FONT><A
href="http://www.pe.com/localnews/corona/stories/PE_News_Local_D_wtrails06.326c6cc.html"><FONT
face=Arial
size=2>http://www.pe.com/localnews/corona/stories/PE_News_Local_D_wtrails06.326c6cc.html</FONT></A><BR><FONT
face=Arial size=2>> <BR>> Norco riders reject arundo removal<BR>> 10:00
PM PDT on Thursday, August 5, 2010<BR>> <BR>> By LESLIE PARRILLA<BR>>
The Press-Enterprise<BR>> <BR>> Temperatures dropped as Bobbie Pope rode a
quarter horse through lush <BR>> bamboo-like tunnels to escape the blazing
Norco heat this week, something <BR>> she won't be able to do next month when
clearing of the well-known trails <BR>> starts.<BR>> <BR>> See the link
above for the full article text and story podcast.<BR>> <BR>> <BR>>
<BR>> _______________________________________________<BR>> PCA's Alien
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size=2>http://lists.plantconservation.org/mailman/listinfo/apwg_lists.plantconservation.org</FONT></A><BR><FONT
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