A thread to place information about trees that we come into contact with, that have health implications.   There was a recent thread on the effects of fig trees, but i thought perhaps a single thread to keep them at hand as a heads up.   This recently occured to one of our team members.   Umbellularia californica aka Californian bay laurel, Headache tree.   I've known (and suffered from) it inducing headaches whilst working on and crushing the leaves, but I didn't know that the leaf oi