Discoloured bone buttons

[ttonon]

Well, I guess a little bit of humor isn't too far off topic, and catswhiskers, I was secretly hoping you'd do some experiments on those buttons.  

 

Tom

[Dana Johnson]

When I was a kid, I was told that you only used the stalks of the rhubarb not the green leaves because that is where the oxalic acid was.  ( Checked in the encyclopedia )Many plants use this sort of distribution to discourage critters from eating the leaves.  The stalks below the leaf have little if any oxalic acid.  Potatoes are similar in that the potato is fine unless very green from light exposure, but the rest of the plant including the fruit contain solanine, a toxic alkaloid.  Sometimes it is the other way round as I discovered when our young dog discovered the bulbs of some of our hyacinths were great fun to mouth and toss around.  This time toxic to critters underground.  We had to dig them all up☹️