My son recently spent a day helping a neighbor clear English ivy from their landscape. He woke on the following day with itchy, spreading blisters on his arm. He says he saw no poison ivy in the English ivy patch…so why is he so miserable?

It turns out that both English ivy, Hedera helix, and Algerian ivy, Hedera canariensis, are known to cause contact dermatitis in sensitive people. Both contain the allergen falcarinol.

Cases of the allergic reaction seem to follow direct contact with the sap of the plants, not the leaves. This contrasts with poison ivy, where contact with any part of the plant can cause a skin reaction.

My recommendation? Wear gloves when clearing English ivy from the landscape and from trees. Avoid getting the sap on your skin, particularly on hot, sweaty days.

English ivy leaf

poison ivy leaf

Virginia creeper leaf