Yes, Umbrella Tree is toxic to dogs!
Dogs accidentally consuming the Umbrella Tree 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).
Umbrella Tree consumption is also toxic to Cats.
Toxic Principles Of Umbrella Tree: Terpenoids, saponins, insoluble oxalates.
More Info About The Umbrella Tree Plant
Scientific Name: Brassaia actinophylla
Family: Araliaceae.
Also known as: Schefflera, Australian Ivy Palm, Octopus Tree, Starleaf.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.