How to Identify Poison Ivy

Poison ivy (Rhus radicans), found in most of North America and a related plant, poison oak (Rhus toxicodendron), found in both Eastern and Western North America, contain urushiol oil. Over half of the population of the United States is allergic to this oil, which can be transferred by contact or inhalation through smoke when such plants are burned.

If you're nervous about getting a poison ivy or poison oak rash, and want to avoid it, you'll need to know how to identify the plant and thereby avoid coming into contact with it. This article explains how to identify each plant.

EditSteps

1. 1
   

    Even your backyard may harbor poison ivy.
   Look for the plant. Poison ivy and poison oak can be found everywhere––the woods, fields, your own backyard, vacant lots, all depending on where you're living. In particular, these plants seem to have fondness for growing along fences and stone walls and they like the edges of forests, fields and sunny areas.
   • Poison ivy is a vine that can also grow as a bush or single plant. If growing in rocky places, it tends to take over from all other vegetation. If growing near something like a tree or a fence, it will twine itself around the object as it grows, creating a dense mass of vegetation which cannot be crossed.
   • 

      Poison oak.
     Poison oak is a shrub but it's perfectly capable of climbing trees. The Pacific or western poison oak tends to be in shrubby areas along the Pacific Coast, while the Atlantic poison oak prefers woody areas in the southeast and west.
2. 2
   Notice the leaves. When seeking to identify the plant, remember this simple phrase: "Leaves grouped in three? Let them be!", as these plants have a cluster of three leaves at the end of a long stem. More identifying indicators of leaves include:
   • The leaves alternate, with three leaflets sitting on a long stem.
   • 

      The middle leaf of poison ivy always sticks out more.
     The leaflets are broad and the two lateral (side) leaflets are smaller than the terminal (end or middle) leaf.
   • 
     The leaves tend to be a bright to dark, waxy green when viewed from above. When viewed from underneath, they appear lighter and fuzzier. In spring, the leaves are usually a bright green, while in fall, they turn red (poison ivy) or bright red or orange (poison oak).
   • However, while these leaves usually appear shiny, they won't always. In particular, do not rely on shininess as an indicator after it has rained recently.
3. 3
   

    Poison oak vines in oak tree.
   Inspect vines before touching, brushing against them or walking through them. When growing as a vine, poison ivy can snake its way along trees. When it grows like this, it is tons of little poison ivy plants growing out of a vine. Always inspect a vine if you need to go near it, and see if it has plants growing out of it.
4. 4
   

    Late summer poison oak.
   Be aware that even when poison oak or ivy changes color, it is still harmful. Despite the color change, the urushiol oil still stays on the leaves.
5. 5
   

    Poison ivy in winter.
   Remain vigilant even during the winter months. Poison oak drops its leaves in winter, and all you see is a bare stem of a vine hanging down. This can also give you a rash. Don't touch any plant you can't identify!
6. 6
   

    Poison ivy berries.
   Check for fruit. If either plant has berries, it will appear as follows:
   • Translucent for both plants.
   • Poison oak fruit tends to be hairy.
   • Poison ivy berries are white or creamish.
   • The fruit tends to stay on the plants all through winter and spring.
7. 7
   Notice that the plants are not poisonous to all creatures. Deer and other animals happily eat poison ivy. Don't be fooled into thinking the plant is safe because you can see other animals consuming it.
8. 8
   

    "Oregon Grape" or Mahonia.
   

    Common wild blackberry.
   Don't confuse poison oak with other plants. Some other plants have two or three similar-looking leaves but aren't the same. They may have spines on the leaf tips (holly or Mahonia) or thorns on the stems (blackberry).
   • If you see a plant that has all the characteristics, but there are sharp ridges on the edges, it's not likely to be poison ivy. Poison ivy has ridges that are more randomly spaced and curved.

EditTips

• Learn to identify these plants if you're allergic. Severe allergies can cause great harm. Bring a picture along until you can spot it immediately.
• Teach children from when they can walk not to touch unidentified plants. This is part of going into nature. This is especially true in winter when plants don't have identifying leaves.
• Bring Technu or other specialized soap with you and apply it immediately upon exposure.
• Go home and wash all exposed skin carefully after a hike. Wash your hands first before rubbing them all over your body. Use warm water and soap.
• Watch when dogs go off leash. Humans are the only ones that are allergic to the oil on the poison ivy leaves, so you wouldn't notice a difference in your dog. So be careful, when you pet your dog or you could get it too. Wash your dog thoroughly if needed. If you have any worries, keep your dog on leash! A bad reaction is also possible with outdoor cats.
• 

   A serious rash.
  Watch for a rash two to three days after possible exposure and begin treatment immediately. See How to treat poison ivy and poison oak for treatment options.
• These plants are also found in Bermuda and the Bahamas.

EditWarnings

• Don't confuse poison ivy with the Virginia creeper. Even though the Virginia creeper has fiveleaves, it's still easily mistaken for poison ivy.
• Poison ivy can be embedded in the Virginia creeper, so never just go rolling around in the Virginia creeper, or there might still be serious consequences.
• Never burn poison ivy as a method to get rid of it. The oil on the leaves will burn and if you breathe in the fumes, chances are you'll get it in your throat or lungs, which will be extremely painful.

EditThings You'll Need

• Photos or images to carry with you to aid identification
• First aid supplies whenever hiking or camping should always include poison plant treatments for rashes