En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Recognizing poison ivy

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
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.
 
rate this answer
Not Yet Rated

Wednesday - June 20, 2007

From: buda, TX
Region: Southwest
Topic: Plant Identification, Poisonous Plants, Vines
Title: Recognizing poison ivy
Answered by: Jimmy Mills

QUESTION:

I am having a difficult time identifying poison ivy. It seems so many plants look like poison ivy can you help me I don't want to kill everything but on the same hand I don't want to itch. Thanks for your help.

ANSWER:

"Leaves of three, better let be". This old aphorism is a good start for identifying the noxious weed (Toxicodendron radicans (eastern poison ivy), however the plant can be quite variable in appearance. Technically the "leaves" are leaflets, but they still contain the active principal urushinol that ellicits the allergic reaction in susceptible individuals.

Two plants that are often confused with poison-ivy are Box Elder Acer negundo (boxelder), and Virginia creeper Parthenocissus quinquefolia (Virginia creeper) . Close examination of the plants reveals that though the leaflets in all three plants seem similar, their arrangements are different. The Poison-ivy of course has leaflets arranged in threes; the Box Elder has five to seven leaflets per leaf arranged in a pinnate fashion, however there can be only three leaflets; and the Virginia Creeper has five leaflets per leaf.

This link is provided to let you "know the enemy", and this one offers some care tips if the ememy gets too close.

 

From the Image Gallery


Eastern poison ivy
Toxicodendron radicans

Ash-leaf maple
Acer negundo

Virginia creeper
Parthenocissus quinquefolia

More Plant Identification Questions

Identification of Queen Anne's Lace look-alike
May 13, 2013 - I am trying to identify a plant/weed that grows here in Austin but I haven't found an exact match in your databases. It looks very similar to Queen Anne's lace and to your photos of yarrow but the l...
view the full question and answer

Name of epiphyte growing on oak trees
June 15, 2006 - Please tell me what the epiphyte growing on the oak trees is.
view the full question and answer

Plant identification
September 30, 2007 - We found this plant or something or other in our yard, in the area we found it usually stays wet and it was behind a old tree that was done. It has three big green leaves with a white stem that kind ...
view the full question and answer

Plant identification
September 25, 2012 - I have a plant that was in a funeral arrangement. The plant has green leaves with darker green spots on it. I do not know what kind of plant it is, nor do I know how much light the plant needs on a ...
view the full question and answer

Plant identification of shrub with thorns and purple flowers
July 05, 2011 - I have a small tree or shrub, it has very small or thin thorns on the branches. It blooms in April / May. The flowers are purple. My mother-in-law said that it has been around for over 100 years, b...
view the full question and answer

Smarty Plants's Facebook profile 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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center