Is English Walnut 'Serr' toxic to cats?

Yes — english walnut 'serr' is toxic to cats according to the ASPCA. Keep it well away from any cat that chews plants; reactions can be significant. Juglans is not individually listed by the ASPCA, yet walnuts are documented hazards to dogs: moldy nuts and hulls can carry tremorgenic mycotoxins (penitrem A) that cause tremors and seizures, and the fatty kernels risk GI upset and pancreatitis. Juglone in hulls and roots is toxic to horses. Remove fallen nuts and hulls and check any ingestion with a vet.

Juglans is not individually listed by the ASPCA, yet walnuts are documented hazards to dogs: moldy nuts and hulls can carry tremorgenic mycotoxins (penitrem A) that cause tremors and seizures, and the fatty kernels risk GI upset and pancreatitis. Juglone in hulls and roots is toxic to horses. Remove fallen nuts and hulls and check any ingestion with a vet. Signs usually appear soon after chewing rather than hours later — watch for drooling, pawing at the mouth, vomiting, loss of appetite, or unusual lethargy after your cat has had access to english walnut 'serr'.

Stay calm. Remove any plant from your cat's mouth and take the plant away. Note how much was eaten and when, and do not induce vomiting unless told to. Call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 and follow their advice; a leaf or photo helps the vet treat it correctly.

The ASPCA classification Growli uses applies to both cats and dogs: English Walnut 'Serr' is toxic to dogs as well. See the full english walnut 'serr' pet-safety guide for both species.

For a similar look without the risk, see the best cats-safe plants list — every plant there is ASPCA non-toxic to cats and dogs.