Poison Ivy Vines

I get a lot of emails from folks asking me to identify whether their plant in question is poison ivy.  If the plant is attaching itself to something, one of the things I look for is how it is attaching and what the attaching mechanism looks like.

Poison ivy attaches itself with dark, hair like aerial roots that may have a slight reddish cast:

Photo Source: Wikipedia

Before it gets to that state, though, the hairs start off small. The following is of my test plant. It is starting to send out vines and therefore is growing these roots. From a distance, they look like hair. Close up, they look like small, woody pieces.

This is another test plant I had a few years ago that started to do the same thing. Notice how there are some roots that really look like hairs and some that look soft:

By using these roots, the plant can attach itself to fences, telephone poles, trees, or just about anything else the plant feels like climbing. 

Why does poison ivy climb? According to Smithsonian Science:

"What triggers a poison ivy plant to climb is a mystery. Some poison ivy plants climb right away from seedlings and others do not. Individual populations of these plants often contain a mix of climbing and non-climbing plants."

When the vines get old enough or thick enough, they can cover an entire tree trunk. Unlike some other plants that can kill the host tree, such as the strangler fig, these vines rarely cause a problem. They can grow to the height of a the tree and even look like the tree.

These vines, no matter how big or small, all contain the same oil that causes the rash, so DO NOT TOUCH.  When fall comes and the plant starts to die back, the oil is pulled from the leaves back into the vines and roots, which means these are not safe to handle or touch at any point.

There are many of these vines where I work. When our crew encounters them, they cut a 6-8 inch piece out of them. This will cause the plant at the top of the vine to die, but it can take a while. They generally just leave the bottom part and it rarely grows back.

That being said, if you choose to remove a large vine, be careful. Clean your tools completely when finished. I have read that extremely small droplets of urushiol oil can spray out when cutting a vine or breaking a root, so clean yourself, your clothes, and your shoes.

The best advice is to get rid of the plant before it starts climbing. However, since the plant often grows mixed well with others, it can be hard to tell what it's up to until it's climbing.

Cats and Poison Ivy

This is my cat, Ram (short for “Ramachandra”, pronounced “rom” as in CD-Rom). He is a rescue cat – someone dumped him off at my property in subzero February weather.  No shelters in town would take him, so cat #4 joined the family.

However, Ram is a holy terror. So much so, in fact, that he lives in the garage. If I leave him in the house unsupervised, he does more damage than an F5 tornado. Thankfully, he loves the garage, probably because there are mice.

He also likes limited outdoor activities. We have coyotes in the area, so he’s not allowed to live outside, but he does run out whenever open the garage opens. He makes his way into the front yard and does cat stuff like climbing trees and rolling in catnip.

What does this have to do with poison ivy, you ask? Well, about a week ago, Ram got out and ran up the tree my test poison ivy plant lives under. When he came down, he came dangerously close to my plant. So, I moved the plant to a location that was likely not going to be interesting to him… the unused half of the driveway.

As luck would have it, Ram got out again a few days later. I went to get the mail, turned around, and – you guessed it – Ram was showing extreme interest in the poison ivy plant. He looked like he was rubbing his face against it. It was dark, so I am not 100% he rubbed it, but it sure looked like he did.

Now, Ram did not and will not have any issues. Cats do not have the same allergic reaction that people do to the urushiol oil in poison ivy. But, I knew that if he did rub it and then rubbed me, I’d have the oil on me and I’d get poison ivy. You see, animals such as dogs and cats will get the Urushiol oil on their fur when they come in contact with the plant and the oil can transfer easily to anything it touches, including furniture, beds, carpet, your hands when you pet the animal, etc.  The oil also stays active for a long time, so it’s not like it will become ineffective soon. This is how people who never go anywhere outside get poison ivy: they touch an object or pet that has come in contact with the plant.

I wasn’t 100% sure what to do, so, I called a vet, who assured me that the cat would not react. Her advise? Dry-rub the cat and then bathe him.

Dry rubbing was good. I used old towels in the garage and vigorously rubbed Ram down. He loved it and stood there purring. He even was ok with me wiping his face a number of times. He seemed to really love the attention.

As for her second piece of advice… wash a cat? Really? I thought to myself - have you ever done this without the cat being tranquilized? Don’t you think the phrase “madder than a wet cat” comes from someplace? In fact, I HAVE washed a cat and have scars to prove it. Cats do not like to be wet, and copious amounts of water are necessary to get the oil diluted to a point that it becomes harmless.

But, I also knew I was not OK with oil all over God only knows where in my house or garage, so I got the bathroom ready. I have one of those flexible shower sprayers and planned to use that. I turned the water on and got it to a decent temperature.

I knew immediately that Ram wasn’t going to go for it. I no sooner closed the bathroom door and started to move him towards the tub that he went completely ballistic. Sounds started coming out of that cat that I didn’t know cats could make. Seriously, I should have filmed this. It was like the exorcist on steroids. He started biting and clawing and I knew there was no way washing this animal was going to happen. Washing the cat could prove more deadly than a rash. So, I let Ram out of the bathroom washed myself instead.

Fast forward 2 days. I have this suspicious set of red spots on my arm that look like I might have scraped myself on something or it could be the start of a rash. It’s been a long time since I have had a rash, so I will have to wait and see. I  also remind myself that I was mowing this morning and had a close encounter with a tree, so that might also be the source of my red area.

I guess I just have to wait. Who knows? Maybe I’ll get to see if the homeopathic remedy Rhus Tox really works. I’ll let you know. In the mean time, the plant has been moved to the unused firepit in the back yard - no where near Ram's tromping grounds.


Update 8/30: I did not have a reaction, so either the cat didn't get into poison ivy, I got it off of him correctly, or I do not react.