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Wednesday - June 26, 2013

From: Los Angeles, CA
Region: California
Topic: Poisonous Plants
Title: Major poisonous plants in California
Answered by: Nan Hampton


Hi! So I'm working on an art project that requires a comprehensive list of poisonous plants within California. I'm looking specifically however, for plants which are fatally poisonous (upon ingestion), and that are either native (preferably) or simply ubiquitous within California. I'm having a hard time finding such a list - if you could point me in the right direction, I'm willing to explore all venues. Thank you!


California Poison Control has a list of Toxic Plants with toxicity ratings in their Know Your Plants publication.  The ones designated as "4" are defined as Major with this explanation:

"Ingestion of these plants, especially in large amounts, is expected to cause serious effects to the heart, liver, kidneys or brain.   If ingested in any amount, call the poison center immediately."

Some of the plants on the list are native and some are not.  You can determine which are native and which are non-native introduced species by searching the USDA Plants Database using the scientific name.   Look for "Native Status" near the top left corner on each species' page.  It will indicate "N" native or "I" introduced.

You can determine more about the nature of the toxicity of the plant by checking (again, use the scientific name) on the following toxic plant databases.   Note that many of the toxic plant databases are geared towards livestock and not necessarily human concerns.

Poisonous Plants and Mushrooms of North Carolina

Plants Poisonous to Livestock and Other Animals–Cornell University

Poisonous Plants–Montana Plant Life

Canadian Poisonous Plants Information System

Pennsylvania's Poisonous Plants–University of Pennsylvania

Veterinary Medicine Library–University of Illinois at Urbana-Champaign

Livestock-poisoning Plants of California


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