Native Plants

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Sunday - March 18, 2012

From: Austin, TX
Region: Southwest
Topic: Poisonous Plants, Vines
Title: Is Bignonia capreolata (crossvine) poisonous?
Answered by: Nan Hampton

QUESTION:

I need to know whether any part of Crossvine (Bignonia capreolata) is poisonous. Am thinking of planting it at an Elder Day Center for people with memory problems and the director insists - no toxic plants allowed. I looked up this plant in the WFC Explore Plants database and at the bottom of the entry there are several Mr. Smarty Plants Q&As about this plant including about its toxicity - however the links for NOT ONE of the answers worked. They all took me to "page not found" web error messages. I then looked through all 197 of your Q&As about poisonous plants. The links for these answers worked but I did not find any discussion of Crossvine. I have searched on the web and on various poisonous plant databases and found only that Native Americans made a tea from the leaves (per Wildflowers of Southwest (Beauregard Parish) Louisiana. I have not found anything about the flowers. Thank you!

ANSWER:

Below are the toxic plant databases that I generally check for listings of poisonous plants. Bignonia capreolata (Crossvine) does not appear on any of them. The fact that it doesn't appear on any of these doesn't guarantee that it is safe to eat or handle; but, since it is a relatively common ornamental plant, it would be logical to assume it would appear on one or more lists if it were dangerously toxic. Poisonous Plants of North Carolina lists many plants that are mildly toxic and it doesn't appear on that database even as "mildly toxic."

Here are the databases I consulted:

Poisonous Plants of North Carolina

Cornell University Plants Poisonous to Livestock

Canadian Poisonous Plants Information System

University of Pennsylvania's Poisonous Plants

University of Illinois Veterinary Medicine Library Toxic Plants

Toxic Plants of Texas

California Poison Control System

Another member of the Family Bignoniaceae, Campsis radicans (Trumpet creeper), a close relative of Bignonia capreolata that even looks a bit like it, is listed in Poisonous Plants of North Carolina as being mildly toxic if eaten in large quantities and as a minor skin irritant. The BoDD (Botanical Dermatology Database) lists C. radicans but says that there are "no properly documented case reports" of dermatitis caused by handling C. radicans.

So, given the information we have, I would not classify any part of Bignonia capreolata as toxic.

From the Image Gallery

Crossvine
Bignonia capreolata

Trumpet creeper
Campsis radicans