Poison Ivy

identifying poison ivy in the outdoors
This mid-summer poison ivy has rare serrated edges on the leaves and usually grows in large patches

Walking along a trail or through the woods is a great way to spend a sunny afternoon. There are so many different things to see-a nice blue sky overhead, birds singing, and flowers to pick.

Unfortunately, one of Mother Nature’s common and poisonous plants is probably growing right along the side of the very trail you are walking on. The next time you are picking flowers while hiking along a woodland trail take a moment and look around.

Poison Ivy grows almost everywhere in North America, including woodlands, along the side of the road, in suburban parks or even your own backyard. This plant is famous for the burning itch and blisters it can cause if its sap comes in contact with your skin.





Poison Ivy (also known as Toxicodendron Radicans), contains urushiol which is a clear liquid compound found within the sap of the plant. The effect in medical terms is an allergic reaction called urushiol-induced contact dermatitis. In layman’s terms, this means it causes extremely itchy blistering sores anywhere that it comes in contact with your body.

learn to spot poison ivy
Poison ivy grows almost everywhere in North America, including the woods

Urushiol binds to the skin where it causes a reddish coloured inflammation, followed by severe blistering and itching. It can take anywhere from a few hours to a week for the reaction to take place. However, urushiol oils can still react several years after exposure.

The rash also be spread through contact with someone else who has urushiol oils on them by holding hands (or other body parts), sharing tools, and even by petting a dog or cat that has just run through a patch of poison ivy. Some people are exposed by untying their shoes after walking through a patch of the plant. Most people will experience the allergic reaction if they come in contact with the sap, but an estimated 15% to 30% of people are lucky and will not experience any reaction.

Poison Ivy can become fatal if the smoke from a burning plant is inhaled, or if the plant is eaten. Some people are extra-sensitive to the reaction and must be hospitalized if they are exposed as an anaphylactic condition can develop. Well over 350,000 people are treated every year in the United States.

The rash can appear to spread across your body; however this usually indicates that different areas of the body received more or less exposure to the plant causing the rash to develop at different rates. The fluid contained in the blisters does not spread the rash. People who are very sensitive to poison ivy may wish to avoid mangoes, as the sap and skin of this poison ivy relative is also poisonous.

identifying poison ivy
During the fall season poison ivy produces white berries that contain a seed and the leaves start to turn red

Treatment for poison ivy varies depending on the situation. If you think you have been exposed but there is no reaction yet, try to wash the affected areas only with strong hand soap. If you can cool the skin in the affected areas, the rash and blisters should be minimized.

An old farmer’s remedy is to put mud or cold cow manure on the affected area after exposure and before the blisters develop to soak up the oils and cool the skin. (Use this remedy at your own risk as infection could occur and your partners may not appreciate your new cow dung scent). The rash usually lasts from one to four weeks.

Calamine lotion along with several natural remedies such as oatmeal and baking soda baths will help to ease the discomfort. If the reaction is serious, see a doctor immediately for a stronger remedy.

Recognizing poison ivy is quite easy. The plant has clusters of three leaves growing from a single stem up to 12 inches tall. Some varieties of the plant can grow on tree- climbing vines and as large bushes in regions with a longer growing season. The leaves are typically almond shaped and 3 to 6 inches long. Poison ivy leaves usually do not have serrations around the edge of the leaf, and do not have thorns. In spring the leaves start as light green with red stems on the plant. (Occasionally in the spring, the new leaves will appear red at first then change to the light green colour).





As the season progresses the leaves turn a dark glossy green and the stems can change to a green colour. The plant flowers with clusters of small tiny white blossoms from May to June.

how to avoid poison ivy outdoors while hiking or camping
Urushiol in poison ivy is very toxic even when the leaves start to die

During August to November small white berries are produced and the leaves can change to an orange-red colour. Urushiol oils can still be active in dead plants so care must be taken in the winter when there are no leaves on the plant. Poison ivy grows in patches, so if you find one plant you are probably already standing in more of it.

Before venturing into the woods familiarize yourself with the plant and teach children the rhyme “leaves of three, let it be” before they go outside to play. If in doubt, don’t touch it. Take a picture and verify what you have found when you get home. There are several herbicides on the market which will kill the plant if you find it growing in your backyard. With a little practice anyone at any age can learn to identify poison ivy and make their stay in the woods much safer and enjoyable.

All the photos in this article can be clicked for larger versions so you can get a closer look for better poison ivy identification.

Copyright 2019 Mike Wilson