0 Avoid having to do this. Make someone else do these things if at all possible. Have a "Mikey".
1 Separate the plant into its various parts—roots, stems, leaves, buds, and flowers. Focus on only one piece of the plant at a time.
2 Smell it. A strong, unpleasant odor is a bad sign, as is a musty or rotting odor. Keep a special lookout for pear- or almond-like scents, which can be evidence of cyanide.
3 Test for contact poisoning by placing a piece of the plant on your inner elbow or wrist for 8 hours. If your skin burns, itches, feels numb, or breaks out in a rash, wash off your skin and don’t eat the plant.
4 If the plant passes the skin test, prepare a small portion the way you plan to eat it (boiling is always a good bet).
5 Before taking a bite, touch the plant to your lips to test for burning or itching. If there’s no reaction after 15 minutes, take a small bite, chew it, and hold it in your mouth for 15 minutes. If the plant tastes very bitter or soapy, spit it out and wash out your mouth.
6 If there’s no reaction in your mouth, swallow the bite and wait 8 hours. If there’s no ill effect, you can assume this part of the plant is edible. Repeat the test for other parts of the plant; some plants have both edible and inedible parts. Starting to feel sick? Time to bring it up.
Note: According to my MDs, allergies take two exposures for your body to freak the fuck out. So if you're allergic to peanuts, the first time your body won't react. The first time is your body developing antibodies or whatever the fuck it does to have allergic reactions. The second time? That's when you swell up like Violet Beauregarde or whatever your body does. So there's that going on too.
Keep a special lookout for pear- or almond-like scents, which can be evidence of cyanide.
Maybe get a few other people to smell it, for this one, bonus points if they're entirely unrelated to you. Not everyone can smell it, and there may be a genetic component to it.
Then also how about a moment of silence for those who figured out how to melt and mix metals, imagine the unholy fumes in that OSHA nightmare, because there's a more toxic way to make bronze before they figured out how to do it with a dash or two of tin as the second ingredient, the "seasoning" for the copper.
Chatted with a friend about this at a sushi place, with how it applies to pufferfish. How many people died before we figured out the right way to prepare it? Also, why was it so important to get to the point where we could safely consume it rather than just stick with using the toxin for medical science use?
I bet they feed it to dogs first. Or maybe pigs. The dogs would just scarf it down and then, in most cases, throw up if it was bad. The pigs would smell it or maybe give it an exploratory chew, but skip anything they detect as bad for pigs.
Lots of things are poisonous to dogs but just fine for us: chocolate, onions, garlic, avocados, cherries, grapes, tomato leaves, rhubarb, coffee, tea (basically any caffeine), alcohol (in the quantities humans drink), macadamia nuts, apricot (for the same reason as cherries: cyanide), starfruit…
At home we basically make this observation everytime we eat artichokes; how the fuck did people discover that this spiky flower from this plant full of spines had the base of each petal commestible?
We cannot eat the things that most of the animals we eat eat.
No animal but us eats stinging nettles. There are all sorts of plants that need serious processing to be good to eat, even then many "safe" plants have almost enough of whatever poison they make to do is damage, but in the normal way we eat them they're safe
Did you know kale has a safe dose which shouldn't be exceeded?
And they goofed up. People now consume plant based drugs like caffeine, cocain, nicotine, THC, pyote, 'shrooms, and so on. These are all poisons. Also, aspirin is based on a poison. Most drugs are based on plants. I'm including mushrooms because those would be discovered the same way.
All plants make toxins, they don't want to be eaten (ripe fruit aside), most of us are pretty good at detoxifying the plants we consider food, but still some people overdose
on vegetables. That kale guy who ate kale smoothies, kale salads, charred kale, and nearly nothing else wound up in hospital having exceeded the dangerous dose
It's a shame that safe limits are not commonly available for everyday plant based food - two bags of vege chips is enough to make many people quite sick, but it won't tell you on the package.