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How to Identify Poison Ivy, Oak and Sumac

Poison ivy, oak and sumac rashes can be painful and dangerous. To avoid them, in this post we’ll talk about how to identify poison ivy, oak and sumac.

It sounds obvious – everyone knows what poison ivy looks like, right? Unfortunately, no.

poison ivy

“Leaves of three, leave them be” is a useful saying, but that only applies to poison ivy, and there are lots of benign plants that sport three leaves.

While hiking with a good friend of mine, who is an avid outdoorswoman, I pointed to a fuzzy vine climbing a tree we were using to cross a creek and told her to watch out for the poison ivy.

She had no idea poison ivy could grow on a vine – even after years of hiking and hunting.

In fact, I’ve never been allergic to poison ivy, so I never bothered to really pay attention to it’s details, however I found out I’m deathly allergic to poison oak (or sumac) I never learned which one so now I avoid them both!

One interesting fact I learned from my allergist is that the allergic reaction caused by poison ivy, oak and sumac is not at all related to the seasonal allergies that so many people (like myself) are plagued with.

So while I have terrible seasonal allergies, I wasn’t at all allergic to poison ivy.

So to protect yourself from unexpected itchy rashes, let’s take a closer look at the three main offenders: poison ivy, poison oak, and sumac.

poison ivy growing up a vine on a tree

How to Identify Poison Ivy, Oak and Sumac

Poison Ivy

Even talking about poison ivy can cause some people extreme anxiety. Touching poison ivy can cause painful rashes, sometimes resulting in large, painful blisters that sometimes need steroids to cure.

About 85% of people are allergic to poison ivy. In the United States alone, approximately 50 million people get poisoned by this plant every year!

Poison ivy has a toxic component called urushiol, which is the one causing the allergic reaction.

Urusoil is present in almost all poisonous plants. It is a clear, yellowish liquid present in the roots, stems, and leaves.

One of the distinguishing characteristics of poison ivy is its leaves. They have compound leaves, which means it has three leaflets with a longer stem in the middle.

The two leaflets on the sides are smaller. It appears shiny with slightly notched edges and a hairy surface.

It is a bit tricky to identify poison ivy right away, not to mention the leaves that change from time to time, depending on the season.

In the spring, the leaves may appear to be red, sometimes with a mixture of green. In the summer, the mature leaves are green while the red leaves are the new ones.

Poison ivy looks beautiful during the autumn season because of its bright orange colored leaves, but still, they are dangerous to touch.

poison ivy turning yellow in the Fall

Cold temperatures, such as the winter season, turn their leaves to deep red. Because of the cold weather, the leaves may fall off, leaving the roots exposed. Even so, the root also contains urushiol and therefore should not also be touched.

In our area, poison ivy is the first plant to turn red in the Fall.

Poison ivy also produces white berries that are often hard to spot right away unless by looking closely.

But during the winter season, when the branches look bare and slender, you could see these white berries more visibly.

Poison ivy can grow tall up around a tree and create a fuzzy, thick vine or invade large areas on the ground.

On our homestead, poison ivy is mostly found on the margins – the edges of tree lines, the floor of our orchards, anywhere where there isn’t a thick layer of leaf litter, or another cover crop.

They are not just found in woods but may even grow in beach towns, sidewalk cracks, vacant lots, and suburbs.

identifying poison oak

Poison Oak

Poison Oak is another dangerous plant that causes an allergic reaction. Just like poison Ivy, its leaves and stems contain a toxic compound called urushiol that causes the reaction.

It is often difficult to differentiate the two, but poison oak can grow as high as 6 feet and can have nine leaflets about 1 to 4 inches long.

Spring season turns their leaves into red or green and gives them green, yellow, and white small flowers. The Summer season makes their leaves green and enables them to produce berries.

If you want to remain safe, it is best not to touch this plant or let your things come in contact with it. Once you come in contact with this plant, your body begins to absorb the allergen.

An inflammatory response will happen.

Because only 15 to 20 percent of people are not allergic to this plant, there is a big chance that you could be in the other 80 percent. If you want to ensure safety, it is best to learn how to recognize this plant.

It is often a bit tricky to differentiate poison oak from poison ivy because of their many similarities.

Poison oak has a more rounded, larger leave with a hairy surface. Make sure to avoid touching the plant or even let your clothes and things come in contact with it.

I believe poison ivy and oak oils can even get onto the fur of your dog and get transferred to your hands when you pet them, so keep an eye on your pets as well.

how to identify poison sumac

Poison Sumac

Poison sumac is another poisonous plant that causes an allergic reaction when touched and inhaled.

This plant can grow up to 30 feet and has a red color stem.

Summer season turns their leaves into medium green while Autumn season turns them into red-orange.

Poison sumac, to me, resembles tree of heaven or mountain sumac.

Poison sumac is one of the most toxic plants in the country. Just like poison ivy and poison oak, poison sumac contains a toxin called urushiol that causes an allergic reaction, but it is much more concentrated in this plant.

All of its parts contain urushiol, which is why touching or getting your clothes or stuff to come in close contact with any part is not encouraged.

Even when it’s dead, its toxic compound remains active.

Inhaling poison sumac must also be avoided as this could cause fluid accumulation and inflammation of the lungs, which is fatal.

Eradicating this plant in your garden requires protective gear and clothing.

When exposed, immediately wash your body with lukewarm water and soap and hose down your stuff before the resin spreads to other things.

You can easily spot poison sumac by the looks of their leaves. Each leaf has clusters of 5 to 13 leaflets per stem with smooth edges.

In the Winter, leaves may begin to fall off, leaving the barks exposed. Poison sumac has rough old barks and smooth new barks.

If you can identify a plant by its bark, then you can avoid being exposed to poison sumac during this time. Make sure not to let your skin brush up against it, even in Winter.

Now that you have learned to identify these poisonous plants, you can now easily spot and avoid them from where they are growing, and hopefully avoid a painful, lengthy rash.