What Chemical Property does this tree have?

Ask The Expert: The tree grows about 6-7 mtrs; very straight and skin is very smooth. When the leaves are chewed and digested, or boiled and drank as tea, it causes continuous diarrhea, depending on the amount taken. No other trees or plants, especially crawling plants, grow closer than 1 meter around. If any crawling plant goes any closer, it’ll eventually dry up and die. – John

Flower Shop Network Plant Expert Reply:

John, Without seeing a picture of the tree, I not sure which tree you are talking about. There is an organic compound that occurs naturally in the leaves, bark and roots of some plants. This organic compound is called Juglone. Plants that produce Juglone create a toxic environment for other plants. The Black Walnut is an example of a trees that produces Juglone. I’m not sure if Juglone causes vomiting if consumed by humans, but I do know that it is toxic to horses.

If you could send me a picture of the tree and its bark, I might be able to determine what the tree is and what chemical it produces.