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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><b><span style='font-size:18.0pt;font-family:"Arial",sans-serif;color:#1F497D'>One part of the research would be to determine how early the vine needs to be removed to save the tree. <o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:18.0pt;font-family:"Arial",sans-serif;color:#1F497D'><o:p> </o:p></span></b></p><p class=yiv9933905954msonormal><b><span style='font-size:18.0pt;font-family:"Arial",sans-serif;color:#1F497D'> </span></b><b><span style='font-size:18.0pt;font-family:"Helvetica Neue";color:blue'>Marc Imlay, PhD</span></b><span style='font-size:10.0pt;font-family:"Helvetica Neue";color:#26282A'><o:p></o:p></span></p><p class=yiv9933905954msonormal><b><span style='font-size:18.0pt;font-family:"Helvetica Neue";color:blue'>Conservation biologist, Park Ranger Office, Non-native Invasive Plant Control coordinator. <br>(301) 442-5657 cell </span></b><b><span style='font-size:18.0pt;font-family:"Helvetica Neue";color:#1F497D'><a href="mailto:ialm@erols.com" target="_blank" title="blocked::mailto:ialm@erols.com">ialm@erols.com</a><br></span></b><b><span style='font-size:18.0pt;font-family:"Helvetica Neue";color:blue'>Natural and Historical Resources Division<br>The Maryland-National Capital Park and Planning Commission<br></span></b><b><span style='font-size:18.0pt;font-family:"Helvetica Neue";color:#1F497D'><a href="http://www.pgparks.com/" target="_blank" title="blocked::http://www.pgparks.com/blocked::http://www.pgparks.com/blocked::http://www.pgparks.com/blocked::blocked::blocked::http://www.pgparks.com/blocked::blocked::http://www.pgparks.com/blocked::http://www.pgparks.com/blocked::http://www.pgpa">www.pgparks.com</a></span></b><span style='font-size:10.0pt;font-family:"Helvetica Neue";color:#26282A'><o:p></o:p></span></p><p class=MsoNormal><b><span style='font-size:18.0pt;font-family:"Arial",sans-serif;color:#1F497D'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:18.0pt;font-family:"Arial",sans-serif;color:#1F497D'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif;color:#1F497D'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>From:</span></b><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'> MAIPC [mailto:maipc-bounces@lists.maipc.org] On Behalf Of Jil Swearingen<br>Sent: Thursday, March 22, 2018 9:21 AM<br>To: Ruth Douglas <cvilleruth@embarqmail.com><br>Cc: MAIPC Listserve <maipc@lists.maipc.org><br>Subject: Re: [MAIPC] A conjecture on invasive vines and tree falls<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><o:p> </o:p></span></b></p><div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>In addition to Steve's suggested "ghost impacts," I'll offer more conjecturing.<o:p></o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><o:p> </o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>Based on personal observations <span style='color:#222222;background:white'>over the past several decades</span>, that are not backed up by hard science, I have watched trees heavily covered with English ivy vines deteriorate over time, lose most of their branches and structure and then die. At some point, even if vines are cut and killed at the base, it is too late to rescue a smothered tree. The tree is too weak to recover. Physically, the heavy growth and dense foliage (mini umbrellas) of English ivy blocks sunlight for the host tree foliage, leads to reduced photosynthesis and growth in the host tree, reduced water availability for the host tree (the vines get most of the water that would otherwise be available to the tree), and the vines probably cause some level of damage to the bark which could lead to increased vulnerability to insect pests and pathogens.<o:p></o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><o:p> </o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>We have identified lots of factors to be studied. Now we just need someone to do the research.<o:p></o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><o:p> </o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>Jil<o:p></o:p></span></b></p></div></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><br clear=all><o:p></o:p></span></b></p><div><div><div><div><div><div><div><div><div><div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>Jil Swearingen<o:p></o:p></span></b></p></div><div><p class=MsoNormal><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>Invasive Species Consultant<o:p></o:p></span></b></p></div><div><p class=MsoNormal><b><i><span style='font-size:16.0pt;font-family:"Arial",sans-serif'>In the Weeds</span></i></b><b><span style='font-size:16.0pt;font-family:"Arial",sans-serif'><o:p></o:p></span></b></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></div></div></div></div></div></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Wed, Mar 21, 2018 at 9:27 PM, Ruth Douglas <<a href="mailto:cvilleruth@embarqmail.com" target="_blank">cvilleruth@embarqmail.com</a>> wrote:<o:p></o:p></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>I’m going to try to contact someone in VDOT (Va. Dept. of Transportation) and someone at Virginia Power to see if anyone there is looking at the role of invasive vines in trees down in storms.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Ruth Douglas</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Invasive Plant Educator, VNPS</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-size:10.0pt;font-family:"Tahoma",sans-serif'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma",sans-serif'> MAIPC [mailto:<a href="mailto:maipc-bounces@lists.maipc.org" target="_blank">maipc-bounces@lists.maipc.org</a>] <b>On Behalf Of </b>Nathan Hartshorne<br><b>Sent:</b> Wednesday, March 21, 2018 6:41 PM<br><b>To:</b> frazmo<br><b>Cc:</b> MAIPC Listserve (<a href="mailto:maipc@lists.maipc.org" target="_blank">maipc@lists.maipc.org</a>)<br><b>Subject:</b> Re: [MAIPC] A conjecture on invasive vines and tree falls</span><o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Perhaps the previous ivy spread had stopped development of an understory that would have helped prevent windthrow since the gaps in a forest can help facilitate it.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Wed, Mar 21, 2018 at 5:32 PM, frazmo <<a href="mailto:frazmo@gmail.com" target="_blank">frazmo@gmail.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>Continuing from the recent thread, it seems intuitively obvious that the weight and windload burden of invasive vine growth would cause mature trees to be more vulnerable to high winds. But I also conjecture that non-native invasive vines may have "ghost" impacts even when they have been removed. Based on personal observations at Long Branch Nature Center in Arlington VA, we have lost dozens of mature trees due to wind storms from Hurricane Isabel (2003) to now. My sense is that a disproportionate fraction fell in areas that had been heavily blanketed in English Ivy growth circa pre-2004.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>Even though the ivy had been removed, the trees fell. The conjecture is that the invasives' growth had altered soil characteristics and tree root growth patterns in ways that left the trees more vulnerable going forward.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>I agree that this whole area seems like a great topic for research and this is just one more angle to consider. Cheers,<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Steve Young, volunteer, Arlington VA<o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><br>_______________________________________________<br>MAIPC mailing list<br><a href="mailto:MAIPC@lists.maipc.org" target="_blank">MAIPC@lists.maipc.org</a><br><a href="http://lists.maipc.org/listinfo.cgi/maipc-maipc.org" target="_blank">http://lists.maipc.org/listinfo.cgi/maipc-maipc.org</a><o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div></div></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><br>_______________________________________________<br>MAIPC mailing list<br><a href="mailto:MAIPC@lists.maipc.org">MAIPC@lists.maipc.org</a><br><a href="http://lists.maipc.org/listinfo.cgi/maipc-maipc.org" target="_blank">http://lists.maipc.org/listinfo.cgi/maipc-maipc.org</a><o:p></o:p></p></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br />
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