This article is from the Pet Owner's Guide to Common Small Animal Poisons, by Julie Dahlke, DVM, a graduate of the University of Minnesota, College of Veterinary Medicine.
Spring and fall are times for seeding and fertilizing and accidental
animal poisoning. Cats and dogs often lick their paws, especially
after walking outdoors, perhaps over newly fertilized lawns. Confine
your pet for a while after you fertilize.