I went to Snopes to confirm that this wasn't just an urban legend, and sadly it isn't. No matter how much someone tells you that "Dogs won't usually eat it," I haven't met a dog yet that doesn't want chocolate, and Cocoa Mulch contains chocolate (IMO this is an incredibly irresponsible claim by Hershey's, that " It is true that studies have shown that 50% of the dogs that eat Cocoa Mulch can suffer physical harm to a variety of degrees (depending on each individual dog). However, 98% of all dogs won't eat it.") I'm sorry, but I'm not willing to play Russian roulette with my dogs' lives.

Chocolate contains theobromine, a chemical toxic to dogs and other pets. Read the Snopes coverage about Cocoa Mulch yourself and protect your pets.