Rent Shop Volunteer Join

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
5 ratings

Wednesday - September 24, 2008

From: Los Angeles, CA
Region: California
Topic: Cacti and Succulents
Title: Are century plants (Agave spp.) poisonous?
Answered by: Nan Hampton

QUESTION:

About 2 weeks ago, I was poked in the arm by a Century Plant, which caused a pretty big bruise to form. I didn't think much of it at first, but now, 2 weeks later, the bruise hasn't healed at all. Should I be worried? Are they poisonous?

ANSWER:

The Botanical Dermatology Database (BoDD) has this to say about the Family Agavaceae (Agave or Century Plant Family:

"Many instances of irritancy and possibly allergenicity resulting from contact with members of the family have been recorded.  The irritant (micro-traumatic) effects are attributable to minute needle-like crystals of calcium oxalate know as raphides, probably aggravated by steroidal saponins, proteases, and perhaps other constituents of the sap.  The allergens remain to be identified....Additionally, the thorny edges of the leaves as well as the needle-sharp leaf tips of many species are capable of nflictinig mechanical injury (macro-trauma)."

If one of the thorns of the leaf of the century plant broke off in your arm, you may have gotten some of the irritating sap inside the wound and there may even be a small piece of the thorn left within.  Whether or not you were exposed to the sap, puncture wounds of any kind are notorious for becoming infected. This is why it is important to remove the thorn as soon as possible and thoroughly clean the wound. Read what the Mayo Clinic has to say about puncture wounds.  It sounds like it would be a good idea to visit your Dr. to see why the bruise hasn't cleared up by now.

 

More Cacti and Succulents Questions

Why is my Agave suffering in Mesa, Arizona?
August 06, 2009 - I live in Mesa AZ, and have an agave that we planted 7 years ago. It grew like crazy with hardly any care whatsoever, until I cut off some of the bottom leaves and 'pups' about a month ago. Recently...
view the full question and answer

Dead leaves on yucca in Georgetown TX
October 18, 2010 - We have 2 6ft and 3 smaller soft leaf yuccas out back in a kidney shaped area with a wax myrtle and a mountain laurel. The yuccas have done great but now two of them have a large number of dead leaves...
view the full question and answer

How to remove plume from Yucca elephantipes in NJ?
August 02, 2011 - In Manahawkin, NJ, how do we cut plume (2" diameter) off 10' Yucca elephantipes?
view the full question and answer

Native plants for a New York, NY apartment?
August 14, 2009 - Dear Mr. Smarty Plants, What are some native Mid-Atlantic/New England plants that can be grown well indoors? I live in an apartment in New York City and have recently realised that the plants I'v...
view the full question and answer

What to do with bloom stalk on yucca
June 08, 2008 - Six years ago, I dug up two small narrow-leaf yuccas from a deer lease outside of Junction, Texas. I planted them in a raised bed in my yard and the smaller of the two survived and grew. To my surpris...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.