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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.



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