Poison Ivy, Poison Oak, and Poison Sumac: How Do They Differ?

A Poison Oak sign standing in front of Poison oak plants.

For many people across the United States, summer weather is associated with time spent outdoors, enjoying the sunshine. Whether you’re hiking or camping for fun, or if spending time outside is a normal or necessary part of life, exposure to harmful plants is a reality you have to be prepared for.

This article will provide all the information necessary to identify and understand poison ivy, poison sumac, and poison oak, three of the most common toxic plants people regularly come in contact with in the United States.


The very first step in dealing with these plants is being able to identify them. While you could be forgiven for thinking that these plants strongly resemble one another (not to mention the many other plant species that you’ll find in the wilderness), there are clear visual signs that will help you to spot and avoid them.

While poison ivy, oak, and sumac are visibly different from each other, they share several key traits. All three species have compound leaves, meaning that each “leaf” is really made up of multiple leaflets that are connected to one another by a thin stem. All three also share the common trait of having a dull, waxy sheen visible on every part of the plant. This is urushiol, the oil that protects the plant by causing the infamous allergic reaction when it comes in contact with skin.  

Poison Ivy and Poison Oak

Both poison ivy and poison oak have three leaflets per branch - this is where the old saying “leaves of three, leave them be” comes from. The leaves of both species range from 2 to 8 inches in length, and both plants have more or less oval-shaped leaves with jagged (often irregular) “teeth” or waves along their edges. You can distinguish between the two plants in that poison ivy leaves tend to be more pointed or jagged, while poison oak has softer, more rounded edges. 

Additionally, the two plants differ in how they grow - poison ivy (like other kinds of ivy) looks like a vine that usually climbs along the ground or more frequently, up the sides of trees or other vertical surfaces. Poison oak on the other hand tends to grow in the form of a bush or shrub with leaves crowning the top of upright branches or stems.  

Poison Sumac

Although poison sumac is closely related to poison ivy and oak, it’s much easier to tell apart from its relatives. Poison sumac leaves are made up of anywhere from 7 to 15 leaflets instead of 3, and the leaflets are arranged in neat pairs along a noticeably red stem. The leaves have smooth edges that taper to a fine point. Like poison oak, poison sumac grows in the shape of a shrub or a small tree, reaching up to 20 feet tall. 

Range and Distribution

Poison ivy grows across the US, found in every state except Alaska and Hawaii. Poison oak can be found throughout the western United States as well as the southeast but is rarely or never found anywhere in the midwest.

Poison sumac is more picky about where it will grow, preferring the wet soil found in swamps or bogs. It can be found across the eastern US, especially in the deep south and along the northeastern coast. 


With a little practice, being able to tell these plants apart should not be too difficult. However, it can often be harder to tell poison oak, ivy, and sumac apart from similar-looking but non–toxic plants. 

Poison ivy for example can easily be confused for Virginia creeper as the two plants will commonly grow together, and both have noticeable red spots where their leaflets connect. However, Virginia creeper leaves are made up of five leaflets, not three. 

Likewise, both smooth sumac and winged sumac can be mistaken for their poisonous cousin. Smooth sumac has more leaflets per stem (between 11 to 31 one) and winged sumac has a thicker branch covered in soft leafy material, making them easy to distinguish to a trained eye. 

Of course, the best and safest course of action is to simply stay away from any plant that even resembles poison ivy, oak, or sumac!


At Tecnu, our goal is simple: to create innovative products that help our consumers solve a problem. 

Our team continually strives to find new and better ways to not only meet, but to exceed the needs and expectations of our customers. We vow to stay on the path of advancement without losing sight of who we are at our core: a driven group of individuals with a desire to help others, whether they be outdoor adventurers, gardeners, athletes, moms, dads, or all of the above.

Tecnu offers the industry’s best treatments for poison ivy, poison oak, and poison sumac. Our Original Outdoor Skin Cleanser and Extreme Poison Ivy Scrub helps wash away the culprit (urushiol) and preps your skin for treatment with our maximum strength Tecnu Extreme anti-itch treatment to give you fast relief!