Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
From: San Marcos, TX
Region: Southwest
Topic: Poisonous Plants
Title: Toxicity of Yucca leaves San Marcos, TX
Answered by: Amy Johnson
The roots, at least, of Yucca constricta (Buckley's yucca) do contain saponins, which, while toxic to humans, are usually poorly absorbed and therefore do not usually irritate unless you are sensitive or allergic to them. Incidentally, beneficial uses of these same saponins have been found for humans as well, usually involving cooking them to remove any toxicity. You mentioned the leaves, and it is possible that some of the sap containing saponins from the plant could have escaped upon contact and caused the intense irritation in your skin, especially if you are sensitive or allergic to it. It's also possible that there was more than just the Yucca itself involved - other pollen or bacteria could have been on the leaf or even your skin to begin with, and the abrasion caused by contact may have allowed one of those to penetrate and therefore irritate the surrounding skin. Hopefully your rash is healing now - such a rash sounds very yucca!
Petals of flowers on cake from London
August 28, 2010 - Hi could you please confirm whether it is safe to position an amaryllis on top of a fresh cream cake (it will not be eaten, nor will the stem touch the cream, it will be positioned in a non toxic vial...
view the full question and answer
Alpacas poisoned in pasture in Texas
October 26, 2008 - Two of my alpacas were poisoned by something growing in two of my pastures. One of the suspects is cussus trifoliata, aka, cow itch vine, sorrelvine. I have searched diligently and can find no refere...
view the full question and answer
Plants safe for donkeys in Foristell MO
August 22, 2009 - I am looking for a plant that can grow next to a farm fence, preferably the length of the fence approx 75 ft. in a long row, one that miniature donkeys can safely eat, if they so choose. I like your ...
view the full question and answer
Pruning the leaves of Sago Palm.
March 10, 2010 - Is it a cardinal sin to remove all the sago palm branches? This winter they were so badly scorched by the cold that hardly a frond went unaffected. So I cut them all off as I needed to get around the...
view the full question and answer
Getting rid of poison ivy, poison oak and poison sumac
July 30, 2011 - How can I rid my yard of poison ivy, poison oak and poison sumac? I have tried roundup, poison ivy roundup and even a clorox solution and nothing seems to kill it, I keep seeing it come up. Any help ...
view the full question and answer
![]() |
Support the Wildflower Center by Donating Online or Becoming a Member today. Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends. |