Here is another dangerous plant that is very invasive: Daphne laureola, commonly called spurge-laurel but it is neither spurge nor a laurel
https://en.wikipedia.org/wiki/Daphne_laureola
"Toxins are in the bark, sap, and berries, and if contacted, the sap is known to cause skin rashes, nausea, swelling of the tongue and coma.
Due to the irritating toxins in the sap, fruit and leaves, wear gloves and other protective clothing when removing or cutting spurge laurel. Older plants should be cut below the soil line to minimize re-sprouting. Volatile plant toxins may be released during cutting, so protective gear is recommended"
I have one that came up on its own in my shaded waterfall garden but I keep it well controlled