View Full Version : Poison ivy question

11-13-2010, 04:23 AM
My research has left me somewhat confused.

I read that the leaves turn red in the fall. Can they turn yellow instead?

Do all the leaves fall off the vines for winter? Think vines winding up trees.

If the leaves fall off, how long does it take to re-leaf - a month? If the leaves come back do they then turn red and the vine produce white berries after that?

Thanks for your help.


11-13-2010, 05:36 AM
I'm not a botanist, but in my experience -

I've seen slightly orange-ish leaves, but I've never seen them be yellow.

The leaves stay off all winter, like any other deciduous plant. So they fall off in October/November, and come back in April/May (I'm in Ontario). The berries come in the late summer, and they stick around for a while, but they aren't really noticeable.

11-13-2010, 11:37 AM
I have some very yellow-leaved poison oak right outside at the moment if that helps you any :)

The P ivy I have is still green, actually. I'm in the south.

I never do notice the berries. We have sumac, too, and I don't always know what is what. It may be sumac out there that's still green.

They all do the same thing, so maybe that gives you some options, at least :)

11-14-2010, 04:46 AM
Backslashbaby, yes, I'm in the south. Does poison oak have the grouping of five leaves each with serated edges?

Would the vine still be poisonous without the leaves?

11-14-2010, 06:29 AM
Poison Ivy has three, Virginia Creeper (which turns red in the fall) has five or more. I can't recall if my little vine of PI (too scared to touch it to dig it out!) turned colors or not, it's bare now. Yes, PI can still give you a rash, leaves or no.

11-14-2010, 07:15 AM
The plants commonly known as poison ivy, poison oak and poison sumac are all assigned to the botanical genus Toxicodendron, which is a member of the sumac family. The three biggies are poison ivy, a common plant in the Midwest and eastern U.S., found mainly in woodlands. Poison oak is common along the Pacific coast, especially in California, and poison sumac is relatively rare, normally found in marshy or swampy areas, and much less often encountered by humans. Which is good, because allegedly it is the most virulent of the three. There are other members of the genus, but these are the three major ones. My recollection is that poison ivy leaves turn red in the fall, not yellow.

I know this for two reasons: 1. I have some botanical knowledge as an offshoot of my professional work. 2. I am allergic as hell to these things.

One of the big problems with them is that, counterintuitively, a person doesn't develop any resistance or immunity to them through repeated exposure. The opposite tends to be true. The more times you are exposed, the easier it gets to be affected, and the worse the rashes get. Fortunately, where I live now (Alaska), none of these plants grow. But I've needed serious medical treatment for the allergic reaction in the past, and it can take weeks to clear up. It's not an insignificant problem.

You absolutely do NOT want to burn these things, for danger of inhaling the smoke, which remains toxic and can cause serious internal problems. And I've read that no human is truly 100% resistant to their effects.

Not all members of the sumac family are toxic to the touch. Normal staghorn sumac is a shrub or small tree that is ubiquitous through much of the central and eastern U.S., usually as a woodland margin plant, often in roadside ditches. Its leaves turn fire-engine red in the fall, and it is easily identified. No toxicity.

Wikipedia has a decent straightforward article on them:


11-14-2010, 07:54 AM
Backslashbaby, yes, I'm in the south. Does poison oak have the grouping of five leaves each with serated edges?

Would the vine still be poisonous without the leaves?

That's what we're calling Poison Oak in my neighborhood, yes. The leaves do look similar to oak leaves, too. I have some trying to climb an oak tree right now that is bright yellow with the cold. It'll be leafless soon.

It is still quite poisonous with no leaves. Those stems, particularly the big ones, will get you every time!

I don't remember when it leafs out again. Some time in spring, but I can't remember if it's early spring or not.

The other kind, I never can tell whether it's really poison ivy. It's poison, but it doesn't always look like the pics say it should. It'd be ivy or sumac as far as I'm aware. I just say avoid it, lol :)

11-14-2010, 08:07 AM
This is kind of interesting. Our 'poison oak' here looks like a combination of what you usually see listed and this pic http://voices.mysanantonio.com/samcoffman/PoisonOak_04.jpg which is said to be Virginia creeper.

I swear to you, the plant I'm talking about is what we call poison oak, and it's quite poisonous. Is it some kind of hybrid? Dunno. But if it looks a little rounder than that VC pic, but carries the leaves the same way (3-5 leaves), it's something poison. I can send ya some, anyone :D

11-14-2010, 10:11 AM
Another useful on-line article:


It really is amazing what a simple goooooogling will do for your curiosity.

And even more amazing that so many people still fail to realize this.

11-14-2010, 06:08 PM
You absolutely do NOT want to burn these things, for danger of inhaling the smoke, which remains toxic and can cause serious internal problems. And I've read that no human is truly 100% resistant to their effects.

You also don't want to take a weed whacker to them and end up inhaling particles. The DH's face swelled up and he got some nasty chest congestion.

Kenra Daniels
11-14-2010, 08:18 PM
The poison ivy along my fence turns red in October and leafs out again in April. The bare vines give hubby a rash if he comes in contact with them.

I'm one of the fortunate few who aren't allergic to PI. Don't know about poison oak or sumac, as I've never had contact with them that I know of. I pull the PI out barehanded every spring. My dad wasn't allergic to it either, but my mom is highly allergic.

11-14-2010, 08:53 PM
Poison Ivy has three leaves that are green for most of the spring and summer. They turns a red/green color during the Autumn. The leaves are kinda glossy as well. If its just a small plant it dies out till spring. If its a big vine, it loses its leaves and looks like a big hairy vine climbing the tree.

11-14-2010, 10:39 PM
I'd just like to state that I read the title and thought I'd get to pull out my Batman knowledge. Almost a little disappointed here. ;)

11-14-2010, 10:41 PM
Thanks, guys.

blacbird, I did google, but I googled poison ivy and the leaves turned yellow not red. I was even looking for the white berries, which didn't turn up. The five rather than three leaves caused some confusion.

I didn't think of googling poison oak, though it was mentioned in the articles. The neighbor had called the stuff poison ivy and I got stuck on that.

It does look exactly like the picture Backslashbaby found, so I'm thinking it is poison oak, or perhaps Virgina Creeper, which, one of the articles I found said, was often mistaken for it, or the other way around.

Thanks for your help. I will not burn stuff. Since it's climbing a tree, I didn't think of the weed whacker.

11-14-2010, 11:01 PM
We really do have problems in some areas with ID, because there must be enough natural variation in these things that the habit and leaves can look too different from pics.

Species roses are like that, too. (I'm on a rose forum).

The oldtimers in a location will tell you whether it's poison or not, whatever it is ;) :) Or you can test it, bwahaha!

I used to not be allergic to them, btw. Then I got a horrible, horrible case after pulling it out, and now I'm allergic to the leaves brushing me, even.

11-15-2010, 01:43 AM
Leaves of three, leave it be. Leaves of four, eat some more. ;) Seriously, poison ivy has three shiny leaves, the vine is allergenic, and it doesn't just grow in the woods, we have it in our yard. I pour boiling water on it in my pathetic attempt to kill it. It's growing around our well, and I don't want to use weed killer there.

11-15-2010, 03:21 AM
Well, if it has to have shiny leaves to be poison ivy, that it isn't. I'm ready to go with Backslashbaby on this one, it looks just like the picture she found.

I'd be inclined to leave it be if it weren't climbing a tree. I'm worried it might harm the tree and/or fell the tree. Sort of awkward place for that. I may be able to get most of it off, but not all. So I know it can keep growing.

I thought/planned to get the vine when it didn't have the leaves. I think it will be less likely to brush me if it's just the vine and no floppy leaves.

Sis is still under the impression that it's not poison ivy, or poison anything. But I have this thread and Backslashbaby's photo of the thing to say, yep, wearing gloves and you've got to hold the bag open for me to drop it in.

A botony reject says thank you again.


11-15-2010, 03:23 AM

I just had a thought. Can you pour salt on it by the well? That shouldn't hurt the well and I understand salt is bad for plants.

Note - salt, paint and pulling up did not stop or slow the whisteria or the kudzu I tried it on. Yes, I recognize both those plants.

11-15-2010, 04:04 AM
One could paint brush killer on the leaves instead of spraying, especially when there are favored plants growing around it that you don't want to kill (or growing around a well).

11-15-2010, 05:04 AM
Here's a link on Poison Ivy:


(I can't believe people actually want, or like this plant!)

And here of Virginia Creeper


And of Poison Oak


And, if you use the site's search function, you can find even more itchy fun plants to read about.

11-16-2010, 04:03 AM
If you touch it and you're highly allergic, like me, it can move through your lymphatic system. I had it on my hands as a child and it popped out under my neck, under my arms and in my ummm 'groinal area.' My mother thought I had been doing something naughty to 'get it there.'

Our family doctor set her straight. I also had it in my eyes a diff. time and one eye completely closed up for a while. I looked like a little girl Frankenstein and couldn't go to school for a week.

11-16-2010, 05:12 AM
Poison Oak is also quite happy to attach itself to other vines; I've seen it intermingled with honey suckle, for instance.

And I first saw it growing in and around scuppernongs, wild grapes.

Ol' Fashioned Girl
11-16-2010, 05:35 AM
Ah! My ol' nemesis: Poison Ivy!

GAH! What horrible memories I have of that stuff... my outdoor cats (another good reason to keep them indoors!) used to bring the oil of it home to me on his fur. And that oil can remain potent on rakes and cutters and any other tools you use to try and remove/destroy it for up to five years.

I also learned the hard way... if you're allergic to poison ivy, you're also likely to be allergic to the skin of a mango - and not the fruit, just the skin.

11-16-2010, 08:19 AM
Tepelus - just read the site on Va Creeper, thank goodness, this isn't that. It's been on the tree several years, I know I kept hoping the neighbor would deal, and it's just the one vine, no kudzu like effort.

I had a friend whose Springer loved the stuff for rolling in and, yes, she was allergic, friend not the dog.

Cats live indoors, poor things, terrible karma, but they really don't seem to mind.

Patrol the small dog yard and take them on walks when they ask.

Thank you all for your help. We keep looking at the pictures, looking at the plant and it didn't match any of the poison ivy pictures. Sis kept saying it doesn't have three leaves, it's not poison ivy. And apparently it wasn't, but poison oak is just as bad.

My skin thanks you.

11-16-2010, 04:53 PM
If you touch it and you're highly allergic, like me, it can move through your lymphatic system. I had it on my hands as a child and it popped out under my neck, under my arms and in my ummm 'groinal area.' My mother thought I had been doing something naughty to 'get it there.'.

That's not how it spreads. The toxin is in the rhus oil and it needs soap to wash it off. Washing with plain water simply spreads it. If it gets on your clothes (and it will) and you don't immediately wash the clothes with soap upon returning home it will infect anything it touches. The classic is you get it on a jacket which you then put into a closet and a few months later wear the shirt that was next to the jacket and get the rash all over your chest.

Standard procedure if anyone in the household is allergic to it should be to put ALL clothes worn in the woods immediately into the washer and the person takes a shower and soaps everywhere.

It's been a long time since I've seen any poison Ivy since the sheep think its tastey. As far as it turning yellow or red, that seems to me to be dependent upon the weather with red favored by a gentle transition through the fall whereas droughts and radical temperature fluxes favor the yellows.