Largely non-toxic for humans
The walnut tree with its nuts and leaves is generally non-toxic to humans.
But: People with sensitive stomachs can react to the leaves with nausea and vomiting (for example when drinking a Walnut leaf teas).
In addition, it cannot be ruled out that the green shell of the walnut fruit leads to poisoning with stomach and intestinal problems (high tannic acid content).
Warning: Of course, you should ALWAYS refrain from moldy walnuts!
Walnut tree partially poisonous for animals
In horses, the heartwood of the walnut tree can lead to laminitis. However, such poisoning rarely occurs, as horses generally do not nibble on tree wood. The maximum danger is from felled walnut trees, on which an edible good happens to be.
In dogs in particular, walnut shells or nuts attacked by fungi can cause symptoms such as vomiting, tremors or even real nerve cramps. The mushrooms are able to develop toxins.
