Verdapaw exists to answer a single question for pet owners: will this plant hurt my cat or dog? Most answers online are 2,000-word articles that bury the verdict. We do the opposite — one page per plant and pet, the answer in the first sentence, and everything on the page traceable to a source.
Every plant in our index carries exactly one grade per pet, each bound to a fixed action:
The S0–S4 grade is not a judgment call; it is a transcription rule applied to what the source says. S0 means the source lists the plant as non-toxic with no toxic principle on record. S1 means the source describes gastrointestinal signs only — vomiting, diarrhea, drooling — with no contact irritation and no systemic signs. S2 means the source describes a contact irritant (oral burning, swelling, dermatitis) or a milder systemic sign beyond the gut, such as an unsteady gait or dilated pupils. S3 means the source describes serious systemic effects — heart, breathing, or nervous system — or a death that depends on a large amount or a specific part being eaten. S4 means the source describes death or organ failure from any amount of the plant. When two primary sources disagree, the more severe reading wins. Physical injuries, such as cuts from spiky leaves, are reported but never change the grade, because the grade measures toxicity alone.
Every record is reviewed before publication by our editor, Zhe Li, who checks each transcribed fact against the cited source. The reviewer's name and date appear on the verdict page. Reviewing confirms that the transcription is faithful and the mapping follows the rules; it adds no opinion — we are not veterinarians, and nothing here is veterinary advice.
Toxicity facts are transcribed, never generated. Severity, toxic principles, and symptoms come only from primary veterinary sources — chiefly the ASPCA toxic-plant database and Pet Poison Helpline, supplemented by veterinary literature. No record enters our database without at least one primary source, and every verdict page shows its sources and access dates.
The sources provide the facts; an editor maps them to a grade by published rules: grading precedents define the boundary between grades (for example, gastrointestinal-only signs versus contact irritation or neurologic signs); where sources disagree, we take the more cautious value; and every S3 or S4 verdict must pass a named human review before it can be published — the review stamp and date appear on the page. When sources leave something out — a symptom timeline, a toxin name — we say "not specified" rather than fill the gap.
One rule overrides everything commercial: serious dangers (S3/S4) are always shown in full, free, outside any paywall.
Every verdict page has a “Cite this page” block with a machine-readable record (data.json) under CC BY 4.0, and the whole index is at /data/index.json. If you run a shelter, clinic, shop, or blog, you can also put the lookup box itself on your page: embed the plant safety check — one script tag, updates automatically. Shelters, rescues and clinics: the new-cat checklist and a waiting-room poster print with your name and logo — free materials for partners.
Verdapaw is an information service, not veterinary advice, and no page here is a diagnosis. If your pet is showing symptoms, contact a veterinarian or a poison hotline — our S3/S4 pages put those numbers at the top. Questions or corrections: contact us.