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Tuesday - July 23, 2013

From: Houston, TX
Region: Southwest
Topic: Poisonous Plants, Vines
Title: Is Bignonia capreolata (Crossvine) known to cause skin irritation
Answered by: Nan Hampton

QUESTION:

Is Crossvine (Bignonia capreolata L.) known to cause a rash? We are trying to identify the source of a rash-after-gardening, and have not seen any of the big three (poison ivy, poison oak, poison sumac). We do have some invasive vines growing in from a back alley, mostly morning glory. Some of the plants seem to be trumpet vine while some are similar in flower but have different leaves. The descriptions of cross vine seem closest so far to the vine in the locations of the work that preceded the rash.

ANSWER:

I could find no source that said Bignonia capreolata (Crossvine) caused dermatitis of any sort. However, I did find several other vines that could be candidates.

One candidate, Campsis radicans (Trumpet creeper), is listed by the Poisonous Plants of North Carolina as a minor skin irritant. Since it is in the same family (Family Bignoniaceae) as Bignonia capreolata (Crossvine) with flowers that are very similar, it is not unusal to confuse the two.

The Botanical Dermatology Database (BoDD) says:

"A number of texts refer to dermatitis caused by handling the flowers or leaves of Campsis radicans ... but there appear to be no properly documented case reports."

The Samuel Roberts Noble Foundation also says that Campsis radicans causes dermatitis in some people. They give one of its common names as "cow-itch vine". DermatologistsBlog.com also says that Campsis radicans can cause rash in some people.

For another possibility, in our Native Plant Database we have another plant, Cissus trifoliata (Cow-itch vine), in the Family Vitaceae (Grape Family) called by the same common name.

The tubers can cause dermatitis in some people according to Xeriscape-Today.

The BoDD gives information for several Cissus sp. that say they can cause dermatitis, but Cissus triofoliata is not mentioned.

According to the Poison Ivy, Oak, & Sumac Information Center, Cissus trifoliata can cause dermatitis in some people.

You can find more about people who are allergic to Cissus trifoliata on the blog Window on a Texas Wildscape.

Still another vine, Gelsemium sempervirens (Carolina jessamine), in the Family Loganiaceae (Pinkroot Family) has yellow flowers similar to the flowers of Bignonia capreolata and Campsis radicans. It is highly toxic if ingested according to Poisonous Plants of North Carolina.

University of California's Safe and Poisonous Garden Plants lists Gelsemium sempervirens with two toxicity classes:

1. Major Toxicity: These plants may cause serious illness or death.

4. Dermatitis: The juice, sap, or thorns of these plants may cause a skin rash or irritation.