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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.

Scientific Name: Hypericum perforatum

Common Name: St. Johns Wort, Klamath Weed

Species Most Often Affected: horses, sheep, goats

Poisonous Parts: all

Primary Poisons: hypericum

Questions possibly pertaining to Hypericum perforatum:

Are these plants really poisonous?

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