[MAIPC] T. radicans

[Servis, Robert]

Poison Ivy is not a Noxious Weed (at least here in Maryland), and I have not heard of it being an Invasive here in the Mid Atlantic.  It is native, and is actually a very healthy source of food for Birds as compared to many of our other, truly Invasive species (Porcelain Berry, Bush Honeysuckle, Autumn Olive,  Bittersweet, etc.).  it is just one that you want to avoid touching as a human, but it doesn’t do any harm to the rest of the ecosystem.   
Margret and Daniel make some good points about the growth patterns of this species in comparison to English Ivy which tend to have many more vines per tree trunk than Poison Ivy, and some of the issues that this causes.  
I'm not claiming to be an expert on poison Ivy, but I've been controlling Invasive Species professionally for a long time and it has never been on my target list in a natural environment. 
The only time I have ever targeted it was for the specific goal of removing it in areas where the public would be likely to contact it (immediately adjacent to trails, sidewalk edges, near parkinglots/playgrounds etc.) 
I would agree with Daniel and say that it is best for Humans to learn to ID it and to stay away from it (or admire it from afar) while letting the rest of the ecosystem benefit from it and the services that it provides. 
As mentioned above control in some instances may be necessary but as a general rule I would leave it alone!
-----Original Message-----
From: MAIPC <maipc-bounces at lists.maipc.org> On Behalf Of MARGARET L CHATHAM
Sent: Monday, April 6, 2020 9:52 AM
To: Susan Gitlin <susan.mclaughlin at alumni.stanford.edu>
Cc: MAIPC Listserve <maipc at lists.maipc.org>
Subject: Re: [MAIPC] T. radicans

I think your informant is mistaken. Poison ivy can coexist without harm to the trees it climbs for ages: it is deciduous, so it doesn’t create a winter wind flag like English ivy to blow trees down; it tends to grow just one vine up a trunk and then branch widely, unlike English ivy again, which often blankets a trunk with vines, holding in moisture & rotting the bark under it; it grows within the canopy, doesn’t take it over like oriental bittersweet or porcelainberry. All in all, a good forest citizen, just not for us when we touch it.

Margaret

> On Apr 6, 2020, at 9:35 AM, Susan Gitlin <susan.mclaughlin at alumni.stanford.edu> wrote:
> 
> Hello, folks.
> 
> I know that poison ivy is a noxious weed, but I believed that was because of harm to human health.  I was not aware that it behaved as an invasive vine, smothering trees a la English ivy.  That would not make sense to me, except in rare cases, because in that case our local ecosystems would have far fewer trees.  
> 
> However, someone today told me that poison ivy smothers and kills trees.  Has this always been the case, or is it now happening due to increased carbon dioxide in the air?  If the latter, is climate change converting our native plants into plants that cause ecological harm?
> 
> If you could share your knowledge on this, I'd appreciate it.
> 
> Thank you!
> 
> --Susan
> _______________________________________________
> MAIPC mailing list
> MAIPC at lists.maipc.org
> https://nam03.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.maipc.org%2Flistinfo.cgi%2Fmaipc-maipc.org&data=02%7C01%7CRobert.Servis%40montgomeryparks.org%7C5e11f6a8bfab4dfead1f08d7da31b52f%7Ca9061e0c24ca4c1cbeff039bb8c05816%7C0%7C1%7C637217779348100501&sdata=yn4CIZgMnNlaqg%2BBZOO3pkkYgtEG8AFcZ8yig7s8jWQ%3D&reserved=0

_______________________________________________
MAIPC mailing list
MAIPC at lists.maipc.org
https://nam03.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.maipc.org%2Flistinfo.cgi%2Fmaipc-maipc.org&data=02%7C01%7CRobert.Servis%40montgomeryparks.org%7C5e11f6a8bfab4dfead1f08d7da31b52f%7Ca9061e0c24ca4c1cbeff039bb8c05816%7C0%7C1%7C637217779348100501&sdata=yn4CIZgMnNlaqg%2BBZOO3pkkYgtEG8AFcZ8yig7s8jWQ%3D&reserved=0