Host an Event Volunteer Join Tickets

Support the plant database you love!

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
Not Yet Rated

Thursday - July 02, 2009

From: Hockley, TX
Region: Southwest
Topic: Poisonous Plants
Title: Removing poison ivy around live oak in Hockley TX
Answered by: Barbara Medford

QUESTION:

We have a large live oak in our backyard, estimated to be over 100 years old. I am working on clearing out the brush that is under the tree. Can I spray commercially available poison ivy killer in this area? Will it cause any damage to the tree?

ANSWER:

No and yes. No, you can't spray poison ivy killer around your tree, and yes, it would damage the tree. Poison ivy killer, regardless of what it says on the container, is a broad-leaf plant killer. The live oak is a broad-leaf plant. The poison has no internal instructions to avoid damaging one broad-leaf plant while killing another.

Just killing the Toxicodendron radicans (eastern poison ivy) is only half the battle anyway. As long as the vines and leaves are there, dead or alive, they can cause terrible allergic reactions in anyone brushing up against them.  Poison ivy loves the environment you are describing- shade, protection, similar plants for camouflage, trees to climb, etc. And, it is also distributed by the helpful birds, so you never really get rid of it.

Examine the plants you are getting ready to attack very carefully, and prepare to pull out the poison ivy, if you find it, with rubber gloves that can be washed free of the oils, and paper towels or newspaper to actually pick it up. It can deposit oils on tree bark, leather gloves and clothes and come back to torment you later. Deposit the paper-wrapped vine in a trash bag and don't let anyone reach in there barehanded to push the rubbish down. Cutting it at the ground will, of course, kill the vine that is going up a tree or bush. A good second step is to paint the cut stub (if it's too big to pull out roots and all) with a broad spectrum weed killer. Do this quickly, within five minutes of cutting, because the plant will try to heal itself over before the poison can get to the roots. Some people even try painting some individual leaves of poison ivy with a disposable paintbrush and the weed killer. This is pretty slow, and you must still be very careful not to come in contact with any of the vine and not to let the poison contact any desirable plants.

If you can get to a sink without touching anything, wash the rubber gloves (still on your hands) with dishwashing detergent, get the gloves off and then wash hands, arms or anything else that came in contact with the vine with the same detergent. Don't delay doing this, once the oil is on your skin, it takes very little time to start developing the allergic reaction. 


Toxicodendron radicans

Toxicodendron radicans

Toxicodendron radicans

Toxicodendron radicans

 

 

 

More Poisonous Plants Questions

hummingbird attractants
May 03, 2012 - I live in Baytown, Texas and am looking for a variety of plants that attract Hummingbirds, but are also pet friendly. I have two dogs, so this is a major concern. I am putting the plants in my backyar...
view the full question and answer

Defense against poison ivy from The Woodlands TX
March 24, 2014 - Hi and thank you in advance for your help. My husband is allergic to Poison Ivy, Oak, Sumac, or something in our yard. We need someone who is very knowledgeable to come and identify any poisonous pla...
view the full question and answer

Is Norfolk pine poisonous to cats?
December 11, 2009 - Is a northfork pine poisonous to cats?
view the full question and answer

Do palm trees put off a toxic smoke when burnt?
December 09, 2008 - do palm trees put off a toxic smoke when burnt
view the full question and answer

Digging wild buttercup from roadside in Mechanicsville MD
May 28, 2012 - Mr. Smarty Plants, is it illegal to dig out wild buttercup in Maryland? I see them along the dirt road or just in the ditch. Since buttercup considered weed, I'm wondering what the law say about this...
view the full question and answer

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