En EspaŅol

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?


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
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

Sunday - May 16, 2010

From: Denver, CO
Region: Rocky Mountain
Topic: Poisonous Plants
Title: Is arborvitate (Thuja sp.) safe for horses
Answered by: Nan Hampton


Is arborvitae poisonous to horses? I want to plant it along the horse pasture. If it is poisonous, what are similar plants that are not poisonous to horses?


Neither Thuja plicata (western arborvitae) nor Thuja occidentalis (eastern arborvitae) appear in any of the toxic plant databases listed below:

ASPCA Toxic and Non-Toxic Plant Lists—Horses

Poisonous Plants of North Carolina

Cornell University Plants Poisonous to Livestock

Toxic Plants of Texas 

University of Pennsylvania Poisonous Plants

Canadian Poisonous Plants Information System

This is a pretty good indication that it would be safe to plant in your horse pasture.



More Poisonous Plants Questions

Is Chilopsis linearis poisonous to dogs in Midland, TX?
June 04, 2011 - Is any variety of Chilopsis linearis (particularly bubba bubba) poisonous to animals? I'm thinking about using it as a source of shade for multiple dog kennels in west Texas.
view the full question and answer

Is Texas ragwort (Senecio ampullaceus) toxic to livestock?
May 05, 2009 - Mr. Smarty Plants, I have a question related to Texas Ragwort (Senecio ampullaceus): I am concerned about toxicity to livestock as well as interested in natural control methods. I was recentl...
view the full question and answer

Natural fibers for lashing bamboo in weaving
May 07, 2008 - I live in Austin and am looking for plants I can use for weaving fibers, e.g. lashing bamboo for a small project. What plants and parts do you recommend? What resources do you recommend for informatio...
view the full question and answer

Beautyberries not poisonous to cats and dogs from Haddonfield NJ
December 11, 2012 - Are beauty berry plants poisonous to cats/dogs? Would like to use branches w/berries and leaves as indoor decorations.
view the full question and answer

Allergy-causing plant in the Dallas/Fort Worth metroplex area
March 17, 2011 - Do you know what is growing (or floating in the air) in the DFW metroplex now, but not growing or floating the rest of the year? I have a 3 year old that has gotten extremely itchy this time of the ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center