Poison oak can be a harmful plant if you touch it, as its urushiol oil will cause a nasty rash.
What's the Difference Between Poison Oak and Poison Ivy?
“Leaves of three, let it be!” “Hairy vine, no friend of mine!” Learn how to spot poison oak, tell the difference between poison oak and poison ivy, and treat a poison oak rash.
What is the Difference Between Poison Oak and Poison Ivy?
Poison oak is a relative of poison ivy. There are many similarities:
- Both plants contain the same toxic resin, urushiol, in all parts of the plant (toxic to humans but harmless to animals).
- Both plants have three leaflets, display white flowers in spring, and can grow as a vine or a shrub.
- Leaflets can range in size from the length of your thumb to the length of your hand.
- A middle leaflet has a notably longer stem than the two side leaflets, though more obvious in poison ivy than in poison oak.
- Depending on the season, leaf color can range from green to orange and even a dark purplish-red.
But they are indeed different plants. In North America, there are two species of poison oak: Atlantic (Eastern) and Pacific (Western).
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How to Identify Poison Oak
- Poison oak is a low-growing, upright shrub that can reach about 3 feet tall, sometimes resembling a vine.
- The leaf shape resembles an oak leaf (hence the name, poison oak), but it’s not a member of the oak family.
- Leaflets are duller green than poison ivy and usually more distinctly lobed or toothed.
- Leaflets have hairs on both sides, unlike poison ivy.
- Poison oak tends to grow at elevations between sea level and 5,000 feet.
- While the fruit of poison ivy is the color of pearls, poison oak fruit (called “drupes”) is tan.
At the end of the day, remember: Leaves of three, let it be. In other words, if you see a plant with clusters of three leaves, don’t touch it!
Poison Oak Symptoms
Symptoms of poison oak include itchy red rashes that resemble burns, swelling, and even blistering.
Symptoms can take 24-48 hours or even up to a week to show up, mainly if it’s your first exposure!
Poison oak, like poison ivy, contains urushiol. This oily substance causes a poison oak rash, which can be almost impossible to avoid. Upon contact with your body, urushiol immediately forms a chemical bond with the skin and causes an almost unstoppable allergic reaction. Urushiol will stay on clothes, pets, or other materials for months, and its potency lasts. You could even get poison oak without going anywhere near it.
The urushiol resin can cause harsher reactions for those who have been exposed to it before. Sensitivity to urushiol might decrease if you do not come into contact with it until later in life. Only about 15 percent of people are resistant to urushiol, so don’t feel safe around poison oak unless you are absolutely sure you are resistant. You also may become sensitive with repeated exposure, so your resistance might be short-lived.
Danger: Smoke inhalation from burning poison oak can send you straight to the emergency room. Avoid burning this plant (and poison ivy)!
Poison Oak Treatment
Treating poison oak within 10 minutes of contact is your best chance of avoiding a reaction.
Urushiol is not water-soluble! Use strong soaps (like dish soap) and wash with cold water to keep the oils from spreading. Cleanse the area of contact within the first 10 minutes, then rinse off with cold water. As urushiol can remain active for years, you’ll want to wash any clothes, items, or furniture that may have come into contact with the invisible oily residue.
If you don’t catch the exposure immediately, treat the resulting itchy rash and blisters topically with calamine lotion, baking soda pastes, aloe vera, and many commercial products. If you don’t mind mixing breakfast and skin care, one tried-and-true remedy for itchy skin is oatmeal. Fortunately, poison oak is not contagious from the leaking serum, just the fresh urushiol.
If poison oak is extremely serious or you develop a severe reaction characterized by fever or feel generally ill, consult your doctor about a prescription. You should also see your doctor if the rash involves the eyes, mouth, or genital areas.
Of course, the best remedy is always prevention; study our photos so you can recognize poison oak.
Have you ever had a run-in with poison oak? Tell us about it in the comments below!
Samantha Caveny
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Good Article, however, the article states that pets are not affected which is not correct !!! Some pets are susceptible to the plant's oily toxin. Also, you can get Poison Oak/Ivy if your pet has run through a patch and rubs up against you or touches you with their fur that was exposed to Poison Oak/Ivy. Also, always wash your clothes after being exposed to these plants since they can hold the toxin for a very long time.
We moved from Colorado to Georgia. I knew about poison ivy but not poison oak. Was weeding a garden and cut up some weeds I didn’t know were poison oak, even walked through them with short pants! Piled them all up in my arms (short sleeves) and took them to our compost pile. About two days later my arms and legs were a MESS along with streaks on my face where I wiped off sweat on my sleeves. Oh my….I then had to live in calamine lotion and went through two packs of cortisone pills before it finally started going away. We laugh about it now, and I have become a “poison plant monitor”. What an experience I will NEVER forget!😳
Believe it or not, my first known contact with poison ivy/oak was on a girl guide outing in the 1960's. There were about twelve of us on a hike and seven of us ended up with a severe rash! Needless to say, we all soon learned to identify poison ivy! Too bad it was after the fact.😅 It was near the end of the school year and several girls missed at least a week of school.
When I was younger say, 19 I was living in the Pacific Northwest and between rides wouldnpick the local blackberries alongside the road and of course everyone said, ‘Don’t eat the ones right alongside the road go in a little. So not bothering to look and wearing shorts o proceeded to pick blackberries whilst wait for rides to work. About two weeks later I noticed a rash. Thinking it was from picking the blackberries I didn’t do anything and it itched sooo bad I finally talked to some locals who told me what it was as I had no clue being from the Midwest. I had it the whole summer and it was near my eye. It just kept on weeping and the oozing kept itching and spreading. It was horrible my first and only encounter as I moved back to the Midwest after that. Up until I had an anaphylactic reaction to a native wasp I had never been so itchy in my life. I just suffered so much with it and was told it can kill you. People have eaten it?! To combat the effects? Not something I would ever try.
As a former backcountry ranger in the Pacific Northwest, poison oak and I are intimately connected to each other. I’ve never found any holistic or OTC remedy to be of much effectiveness for the agonizing rash. After having it over 200 times I can definitively say, the only effective remedy is complete avoidance. If you do happen to get it and are near the coastal areas a brown algae called laminaria if rubbed directly on the rash area will give relief, tested repeatedly on myself and hundreds of backpackers! You’re never too old to play outside!
I can walk past poison oak or ivy and catch it! I'm that allergic to it. It usually takes several days to a week for it to show up and being from SWVA I'm constantly exposed to it. I do a good majority of the lawn work so I just have to deal with it a couple to three times a year. I almost always end up at the ER for shots and a prescription of steroids. Stoping off at the pharmacy for a box of Benadryl on the way home. I recommend Domboro Sulfur Solution for irritation or Technu spray works well also. If you are holistic and prefer natural solutions, wild Touch Me Not when crushed and applied to the affected areas. Even with treatment I have had poison hang on for over a month. Whatever works for you, good luck and don't scratch. :(
I live in the Sonoran Desert so I never gave poison oak or poison ivy a thought — until I ignorantly ran into poison ivy while bushwhacking to find a spring. I had no idea what was wrong with me the next day and when the doctor at urgent care told me, I was shocked! You can bet I watch out for leaves of three now, even in the desert! Thank you so much for the information- I screenshotted the photo so I can refer to it when in doubt! That stuff is awful!
I've always been told that poison oak is a western North America plant but you say there is an eastern variety. What does it look like and what is its range? Does it look very similar to the western variety and is it present on Long Island, NY?
Really? I grew up in Southern Ohio and there was poison ivy everywhere. Spent 40 years in New Mexico, and never saw it - likewise friends and relatives in various parts of Texas and up the entire West Coast. So I always thought it was an Eastern plague, although I see other commenters has encountered it in the West). Now I've relocated to Tennessee and to our sorrow, have found that the woods on our property have healthy growths of it. Frankly, I'm not sure whether we have poison ivy or poison oak, or both, the descriptions and pictures cover many plants that are twining up our trees. Clearing out a couple of fallen trees made for a lasting adventure involving urgent care.
On the bright side, poison ivy is one of the earliest blooming plants, coming out in late January around here. I've never seen the blooms myself, but my honey bees find them, and bring back bright red pollen. They need early blooming plants for pollen to feed the young larvae (who knew?) and there's no urushiol in the nectar or pollen. Also note, LOTS of plants have 3 leaf growth patterns - wild blackberries, for instance, which we also have in abundance. Once the stray blackberry shoots are a couple feet tall you can definitely tell the difference though.
I have been battling poison oak this past week. I finally ordered jewelweed salve from amazon and it worked so fast. I had scabby, pockmarked, quasi-modo cheeks and that salve worked right away. It is noticeably better after just a few hours and so much relief.
