Yes, Golden Ragwort is toxic to dogs!
Dogs accidentally consuming the Golden Ragwort plants can show the following clinical symptoms: Vomiting, Prolonged Depression, Incoordination, Hypersalivaton, Sleepiness Or Excitation, Dilated Pupils, Low Body Temperature, Low Blood Pressure, Coma, Seizure And Death (In Rare Cases).
Golden Ragwort consumption is also toxic to Cats and Horses.
Toxic Principles Of Golden Ragwort: Pyrrolizidine alkaloids.
More Info About The Golden Ragwort Plant
Scientific Name: Senecio species
Family: Compositae.
Also known as: Ragwort.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.