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"Poisonous" does not mean deadly. Some manifestations of toxicity are subtle. The dose, as always, determines if a plant is safe source of nutrients or a toxic hazard.

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BRIEF: Could you give me some information about the toxicity of these plants?

Your list was very extensive. I was surprised to find so many of the common garden variety plants included(e.g.flax,iris,chives,rhubarb).It would be helpful to me as an amateur gardener to know how all off these plants are poisonous. Are they poisonous upon ingestion or to the touch. To what degree will they cause illness or death. Does this apply to humans as well as animals. Some of my poisonous plants have been eaten off. Why would an animal eat a poisonous plant? (bleeding heart).


These pages are for livestock that eat a lot of plant. Flax can have cyanide-releasing compounds in them. Iris has toxic bulbs (eating) and some people get a rash from touching it, chives, onions, etc. have some oxidants that can cause metHb and anemia if eaten in large quantities by cattle, and rhubarb leaves contain soluble oxylates that can kill a variety of stock and people, too.