En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
3 ratings

Thursday - December 01, 2011

From: Knoxville, TN
Region: Southeast
Topic: Poisonous Plants
Title: North American Plants with Poisonous Thorns
Answered by: Becky Ruppel

QUESTION:

Are there any plants in North America that possess poisonous thorns?

ANSWER:

In North America there are few plants that have poisonous thorns.  The members of the Solanum (nightshade) genus have thorns and are reported to cause injuries that are slow to heal due to poisonous thorns.  Many members of the nightshade family (Solanaceae) have many poisonous parts (i.e. leaves, stems, fruit, roots, seeds) that cause severe irritation to mammals.  The members of this family are widely distributed across North America. 

Another group of plants that have poisonous “thorns” is Stinging Nettles.  They have tiny hairs on the underside of their leaves that ‘sting’ and cause skin irritation and a burning sensation if they are brushed against. 

Finally, most plants that have thorns can cause mechanical injury, and some injuries result in pieces of the thorn breaking off in the skin.  It would seem as if these plants had poison, but in fact, the swelling and redness around a wound is caused by a foreign object logged in the skin. 

Considering plants outside of North America there are several plants from Africa that have poisonous thorns such as Gymnosporia buxifolia or Dichrostachys spp

I acquired my information about thorny plants from the Botanical Dermatology Database.  There is lots of information there if you would like to read further about the affects of plants with thorns. 

 

More Poisonous Plants Questions

Are Cleveland Pear trees in Georgia toxic to horses and/ or dogs?
June 02, 2009 - Are flowering Cleveland Pear trees (Pyrus calleryana) poisonous to horses and/or dogs? I have read that the prunus species are, does that include pear trees? Please help!
view the full question and answer

How toxic are milkweed (Asclepias spp.)?
November 01, 2011 - We are considering a monarch waystation for our local elementary and are concerned about milkweed toxicity. Would it be safe to plant it in reach of children?
view the full question and answer

Non-toxic, non-invasive native flowers for horses
October 12, 2008 - Hi I have a couple areas in and bordering horse pastures that I would like to plant with native flowers. I can find lists of toxic flowers but not non toxic native ones. Id like non -toxic non-invas...
view the full question and answer

Is the California Poppy posionous to dogs?
April 16, 2010 - Can you tell me if the wild orange-colored California poppy is poisonous to dogs? They grow like weeds in my yard. Thanks.
view the full question and answer

Does Virginia creeper cause a rash?
July 09, 2015 - Does Virginia creeper cause a rash to everyone or those who are only allergic as in an allergy like a peanut allergy? Is it something that should be avoided like poison ivy? And does the sap stick to ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center