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Sunday - October 12, 2008

From: Butler, PA
Region: Mid-Atlantic
Topic: Poisonous Plants
Title: Non-toxic, non-invasive native flowers for horses
Answered by: Nan Hampton


Hi I have a couple areas in and bordering horse pastures that I would like to plant with native flowers. I can find lists of toxic flowers but not non toxic native ones. Id like non -toxic non-invasive native flowers does such a list exist?. In particular are the hyssops toxic to horses. Thanks


As far as I know, there are no lists that contain only non-toxic, non-invasive native plants; but, as you say, there are lists of toxic plants.  Here are several toxic plant databases:

Universtiy of Pennsylvania's Poisonous Plants Database

Poisonous Plants of North Carolina

Cornell University's Plants Poisonous to Livestock and other Animals

Canadian Poisonous Plants Information System

Texas Toxic Plant Database

In the five toxic databases above, I could find no listing of any species that has the common name of hyssop (Genus AgastacheGenus Bacopa or Genus Gatriola).  So—even though absence from a list is not a guarantee that a species has no toxicity, absence from 5 different lists makes a better case that the plant is not toxic.

Now, for other flowers you might like to plant there, you can check on the five lists above for their toxicity.  I suggest that you look them up under their scientific names rather than by their common names since the scientific names are generally standard no matter where you live.  If you visit our Recommended Species page and select 'Pennsylvania' from the map there, you will bring up a list of commercially-available native plants recommended for Pennsylvania.  You can also find a "Roadside Use of Native Plants" list for Pennsylvania from the US Dept. of Transportation Federal Highway Administration.









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