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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: Need more information on these plants...

I have been searching through your website for information on poisonous plants but seem to be having trouble finding information on the plants that I need to research. If possible could you please tell me where I can find detailed information on the following plants: Acokanthera oblongifolia Castanospermum australe Cestrum nocturnum Grevillea 'Robyn Gordon' Helleborus orientalis Hyacinthus orientalis Lantana Camara Melia azedarach Taxus baccata Zantedeschia aethiopica


>Acokanthera oblongifolia- Contains the deadly cardiac glycoside and Na channel blocker ouabain. This is the famous arrow poison of South African fame. Should only be poison if injected, but I wouldn't chew on these twigs if I were you... >Castanospermum australe- One of your native Australian plants, but I've seen it in Southern California, too. Causes severe gastroenteritis in cattle, horses and people. Roasting the seeds doesn't help. >Cestrum nocturnum- We had this all over our front porch in Davis, California. Really annoying sweet smell. Poison enough...contains nicotine and some novel saponins. Can paralyze the lungs, cause nausea and spasms, delerium. A related species has enough vitamin D in one of the glycosides to poison horses. >Grevillea 'Robyn Gordon'- This grows in California, too, and contains HCN-releasing compounds, but I have never heard of it hurting any animals. On the other hand, beekeepers hate it, because it must have a dye in it because if harvested with lighter colored nectars, the honeys come out badly discolored . >Helleborus orientalis- Has both cardiac glycosides (like foxglove) and ranunculin (like the rest of the buttercup family). The first causes heart problems in humans, the latter causes burning, irritation in the mouth and gastrointestinal symptoms. >Hyacinthus orientalis- The bulbs cause severe gastroenteritis when eaten. Some dermatitis from plant and oil reported. >Lantana Camara- Some varieties are very toxic, others not much at all. Can causes liver damage in cattle and photosensitization secondary to that damage. Can cause weakness, GI problems, and circulatory collapse. On the other hand, I have seen schoolkids gobble down handfulls of the berries with seeming impunity. Lots of research on this plant was conducted in Australia; why not contact Prof. Seawright in Queensland. I'll bet they are up to their necks in it. >Melia azedarach- An animal would need to eat more than a little, but humans and livestock have both been poisoned (people on the fruit). GI symptoms and confusion, convulsions and death if enough is eaten. >Taxus baccata - Major threat to any animal that tastes it. A few mouthfuls can kill large animals. Under no circumstances can yew leaves or prunings get near animals that might eat them. >Zantedeschia aethiopica - If chewed on it will cause intense pain and inflamation of the mouth and lips. Caused by microscopic needles of crystaline oxylates. Probably enhanced by other toxins, too. Rarely fatal unless swelling of throat is so bad it stops breathing. One way or another, animals don't try this stunt twice. Despite the title, Poisonous Plants of California is an excellent resource for Australians; as are a number of publications from the Animal Research Institute in Yeerongpilly, Q-land.