Mushrooms are the one area that I avoid completely. I’m sure there are edible ones I could learn to identify, but there are entirely too many chances for a mistake being lethal that it’s not worth the risk.
Your “Doctors” were probably both right, depending on which book they were coming from. The same item in two different books can be listed as both edible and toxic depending on the time of year it was sampled, how sensitive one is to the “toxin” and whether an upset stomach completely unrelated to the plant was thought to have been the result of poisoning.
The common pokeweed is both edible and poisonous depending on what part and what time of year you harvest it. I’ve eaten the young shoots for years and never had so much as heartburn, but there some who would avoid it out of an abundance of caution.
As they say, Your Mileage May Vary.
One of the delights of her life was mushroom foraging. She'd be gone a whole day, harvesting from her favorite haunts and bring home baskets and baskets of mushrooms.
As fate would have it, she was in her late 80s, lying on her death bed, in hospital, of stomach cancer. When the end was near, we were summoned to be with her. When I arrived, her sons and daughters [she had 11 children] were crowdwed around the bed. I recall this day so well, I was in my late teens then, and a lull in the conversation of sharing memories and good times, and in an effort to keep her mind off her pain. I piped up and said, "Gram, I'll always remember the delicious pot of mushrooms you'd make. I don't think any of us really were taught which mushrooms to pick were the *good* ones" How could you tell?*
She replied: *I didn't.*
Well! The look of horror and disbelief on the faces surrounding her bedside was almost funny. Most of us did laugh....but she quickly recovered by saying....when you cook wild mushrooms, always cook them with a real silver dollar in the pot. If the silver coin turns black...throw them out.
I always wondered why she kept a silver dollar on the stove shelf. Heh.