There are toxic plants everywhere, if you can recognize what to plant and what not to plant you're ahead of the game. This will give you specific plants to avoid.
Keep an eye out for apricot. Prunus armeniaca (Apricot) produces hydrogen cyanide. It is found mainly in the leaves and seed and is readily detected by its bitter almond like taste. Symptoms of an apricot poisoning will include anxiety, breathing difficulty and convulsions. There is occasionally death associated with the poisoning and it follows a collapse and then a sudden death.
Step2
Avoid cicuta maculata (Spotted Cowbane, Water Hemlock, Spotted Water Hemlock). Described as a "violently poisonous plant," water hemlock deaths are very painful. The body will be spastic and convulse, followed by drooling, nausea and mass delirium. All parts are poisonous, especially the roots of it. It was a plant used by Native Americans for suicide. Take immediate action to get help if you suspect a hemlock poisoning as it is a fast killer.
Step3
Don't plant Xanthium strumarium (common Cocklebur) from the daisy family, this plant has a high toxicity rating for cattle, less so for house pets. Signs include gastrointestinal disorders, cardiac symptoms, behavioral and breathing changes. Care should be taken that the plant isn't in grazing fields or hasn't fallen into feed containers. Buying seed and feed from reputable dealers is a better and safer bet.
Step4
Avoid onoclea sensibilis (Sensitive Fern) the toxic element in sensitive fern is not known but toxicity has been seen in horses fed hay that had the fern. Animals are seen staggering with an abnormal heart rate and muscle tremors after ingesting. All parts of this plant are toxic; the roots being the most toxic.
Step5
Nix caladium hortulanum (Elephant Ears) contains calcium oxalate crystals which clinically produces intense oral irritation and burning. Signs will include excessive drooling, vomiting, increased difficulty in swallowing and general mouth and throat problems.
Tips & Warnings
Look these plants up and recognize how they appear. Don't plant them in your garden if you have small kids or pets that wander.
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