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Do Not Touch

Poison Ivy (Leaves of Three – Let it Be!)

Each leaf of poison ivy consists of three leaflets. These compound leaves change seasonally from dark green to yellow, purple or red. The perennial plant may carpet the ground or stand upright 60-90 cm tall. It can also climb nearby trees as a vine.

The oil (urushiol) in all parts of the poison ivy plant causes blistering and rashes if it comes in contact with exposed body parts. This oil can stick to clothing, boots, tools and pets. It can easily be transferred to the hands, face and other people who have not been directly exposed at all. Some individuals have never suffered any ill effects after exposure; however, they should not assume that they are immune for all time.

Jewelweed to the Rescue!

Jewelweed is best known for its skin- healing properties. It is plentiful in the wild and not hard to find once you learn to identify it. The plant is often found growing near poison ivy or stinging nettle. The leaves and the juice from the stem of jewelweed can be used as a topical treatment for poison ivy.

Wild Parsnip

Wild parsnip is common in Eastern Ontario and is a concern because humans can develop a severe skin irritation from contact with sap from the plant.
The plant chemicals, called psoralens, cause phyto-photodermatitis: an inflammation caused by the interaction between plants and light. Once the chemicals in the sap are absorbed by the skin and energized by UV light on both sunny and cloudy days, they bind to DNA and cell membranes, destroying cells and skin. This causes a wild parsnip “burn” which can leave unsightly scars.

If the sap gets into the eyes, it may cause temporary or permanent blindness. Information to assist in identifying poison ivy and wild parsnip can be found online at Wild parsnip | and  Poison Ivy | Weed identification guide | .


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