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Hi All<br>
I am not familiar with the mile a minute vine eating weevil but here in
NY a colleague of mine at Cornell University, Bernd Blossy in conjunction
with our conservation department released purple loosestrife eating
beetles as long as 16 years ago. I considered this bio control program a
failure until this year. I am not sure why, but this year the purple
loosestrife is 99% gone from literally thousands of acres of wetlands,
roadsides and virtually everywhere it had become established within my
county. It may take many years for such releases to work but this year
the effect is almost astonishing. <br>
I also am pleased to read that some people realize that broad spectrum
herbicide applications to eradicate invasive plants may do far more harm
than good by creating biological vacuums which will soon be quickly
colonized by other invasive plants while inadvertently killing some of
the plants one wants to preserve in the first place. I think
resource managers need to focus more on what is the desired outcome of
any actions they take before they take them. Simply killing invasive
plants for the sake of killing them (gratification?) is not necessarily,
in my opinion, a desired outcome unless one can accurately predict what
will replace them when they are gone. Assuming desirable native plants
will automatically become reestablished once the exotic invaders are
killed is a naive assumption. Think before you spray!<br>
Bob<br><br>
<br>
At 09:25 AM 7/17/2007, you wrote:<br>
<blockquote type=cite class=cite cite="">
<font face="Times New Roman, Times"> <br>
<hr>
<div align="center"></font></div>
<font face="tahoma" size=2><b>From:</b> Hough-Goldstein, Judith
[<a href="mailto:jhough@udel.edu" eudora="autourl">
mailto:jhough@udel.edu</a>] <br>
<b>Sent:</b> Monday, July 16, 2007 9:10 AM<br>
<b>To:</b> ialm@erols.com<br>
<b>Cc:</b> ma-eppc@yahoogroups.com; rreardon@fs.fed.us;
elake@udel.edu<br>
<b>Subject:</b> Mle-a-minute biological control<br>
</font><font face="Times New Roman, Times"> <br>
</font><font face="arial" size=2>Mark,<br>
</font><font face="Times New Roman, Times"> <br>
</font><font face="arial" size=2>With respect to your comment
"Bio-control is having mixed success according to reports", I
just want to remind everyone that this is only the third year the
mile-a-minute weevils from China have been in the field, and in fact the
majority of the releases so far were done in 2006, with a few in 2005 and
very few in 2004. Most consisted of relatively few insects. It is normal
for it to take some time before anything definitive can be said about the
effectiveness of an agent - at least 3 years, and sometimes up to 10
years. The insects take time to build up in numbers, and in some cases
they also need time to adapt to regional conditions. So far we know that
the weevils can establish in a variety of habitats, produce multiple
generations during the season, and disperse readily to new patches. As to
impact on the plant populations, time will tell.<br>
</font><font face="Times New Roman, Times"> <br>
</font><font face="arial" size=2>Judy Hough-Goldstein<br>
_______________________________<br>
Judy Hough-Goldstein, Professor<br>
Dept. Entomology & Wildlife Ecology<br>
531 South College Ave.<br>
University of Delaware, Newark DE 19716-2160<br>
<a href="http://ag.udel.edu/enwc/research/biocontrol/index.htm">
http://ag.udel.edu/enwc/research/biocontrol/index.htm</a><br>
</font><font face="arial" size=2 color="#000080"> <br>
<hr>
<div align="center"></font></div>
<font face="tahoma" size=2><b>From:</b> Marc Imlay
[<a href="mailto:ialm@erols.com" eudora="autourl">
mailto:ialm@erols.com</a>] <br>
<b>Sent:</b> Tuesday, June 26, 2007 9:34 PM<br>
<b>To:</b> 'Aliens-L@indaba.iucn.org'<br>
<b>Subject:</b> Mile-A-Minute, Polygonum perfoliatum<br>
</font><font face="Times New Roman, Times"> <br>
<br>
</font><font face="Times New Roman, Times" size=4> <br>
</font><font face="Times New Roman, Times"><b>Three of us used garden
rakes followed by hand pulling in Little Paint <br>
Branch</font> Park<font color="#000080">, </font>Beltsville
MD<font color="#000080"> </font>on June 22, 2007 and removed 20% of <br>
<font face="Times New Roman, Times">the massive 25’
by</font><font face="Times New Roman, Times" color="#000080">
</font><font face="Times New Roman, Times">100’ patch of Mile-Minute in
an open area <br>
in 2 hours. For example, the three volunteers in 15 minutes used <br>
the rakes very gently to remove about 80% of the Mile-a-Minute <br>
in a 20’ x 20’ patch about 50% invasive vine cover over 50% native <br>
cover including sensitive fern, asters, sycamore and sweet gum <br>
seedlings and Virginia creeper. The herbaceous natives were not <br>
damaged and it was then easy enough to hand pull the remainder in <br>
30 minutes. When we tried to pull
very</font><font face="Times New Roman, Times" color="#000080">
</font><font face="Times New Roman, Times">hard at another
spot</font><font face="Times New Roman, Times" color="#000080">,</font>
<font face="Times New Roman, Times"> native <br>
plants, including a virgin creeper, were damaged. Hand pulling alone
<br>
would have been seen as hopeless and herbicides would have <br>
damaged the natives. Bio-control is having mixed success according <br>
to reports. Cheers.<br>
<br>
Marc Imlay<br>
Laura Malick<br>
Mike Breen <br>
</font><font face="arial" color="#000080"> <br>
</font><font face="Times New Roman, Times">Marc Imlay, PhD<br>
<br>
Conservation biologist, Anacostia Watershed Society<br>
(301-699-6204, 301-283-0808 301-442-5657 cell)<br>
Board member of the Mid-Atlantic Exotic Pest Plant Council,<br>
Hui o Laka at Kokee State Park, Hawaii<br>
Vice president of the Maryland Native Plant Society,<br>
Chair of the Biodiversity and Habitat Stewardship Committee<br>
for the Maryland Chapter of the Sierra Club<br>
</font><font face="arial" color="#000080"> <br>
</b></font><br>
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