Is Dryopteris dilatata 'Crispa Whiteside' toxic to cats?

Mildly. The ASPCA lists dryopteris dilatata 'crispa whiteside' as mildly toxic to cats — a chewing cat typically gets mouth irritation, drooling, and vomiting rather than a medical emergency, but it is still best kept out of reach. Dryopteris (buckler/wood fern) is not individually listed in the ASPCA Toxic/Non-Toxic Plant database. Dryopteris rhizomes are known to contain filicic acid and related compounds historically toxic to livestock and people, so do not assume this cultivar is pet-safe. Treat as uncertain to mildly toxic, prevent pets from eating it, and verify with a vet.

Dryopteris (buckler/wood fern) is not individually listed in the ASPCA Toxic/Non-Toxic Plant database. Dryopteris rhizomes are known to contain filicic acid and related compounds historically toxic to livestock and people, so do not assume this cultivar is pet-safe. Treat as uncertain to mildly toxic, prevent pets from eating it, and verify 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 dryopteris dilatata 'crispa whiteside'.

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: Dryopteris dilatata 'Crispa Whiteside' is mildly toxic to dogs as well. See the full dryopteris dilatata 'crispa whiteside' 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.