Here are a list of links for more information on hazardous substances your pet should avoid.

Plants Toxic to Animals 

Poisonous Plants N.Carolina (with pictures)

National Animal Poison Control Center (Household hazards)

UC Davis Toxic Plants page

Poisonous Plants for Dogs and Cats (List of Names, Veterinary Partner)

Non-Toxic Plants (List of Names, Veterinary Partner)

Plants and your Cat (Cat Fancier's Association)

Easter Lilies can be deadly for your cat!!!

Common Cat Toxicities (Cornell University)

Ten Tips for a Poison-Safe Household (Dog)

Ten Tips for a Poison-Safe Household (Cat)

Winter and Holiday Hazards for Cats