Yes, Tree Philodendron is toxic to dogs!
Dogs accidentally consuming the Tree Philodendron 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).
Tree Philodendron consumption is also toxic to Cats.
Toxic Principles Of Tree Philodendron: Calcium oxalate crystals.
More Info About The Tree Philodendron Plant
Scientific Name: Philodendron selloum
Family: Araceae.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.