Many dogs will graze on grass, especially when it's wet from rain or the sprinkler. No one is sure why they eat it.
Some breeders think dogs do this because they love the taste of grass, while pet owners swear their dogs do it because they love the texture in their mouth. Natural health advocates postulate that grass fulfills some nutritional deficiency caused by a diet too heavy in meat while some veterinarians swear dogs use grass as a natural syrup of ipecac to purge unpleasant things from their systems (think garbage can contents, litter box crunchies, etc.).
While the reason is an imponderable, the end result of canine grass-grazing is known widely: Dogs tend to vomit quickly after eating grass.
Dogs have a well-developed vomiting center, which makes them vomit more readily than other animals. No, you don't have bulimic bulldogs who think their flanks are looking flabby. This ability to seemingly ''vomit at will'' is a protective mechanism dogs have retained to expel substances that may be poisonous, harmful or irritating.
''Although we commonly receive calls on dogs vomiting after eating grass, we don't feel that grass-eating is anything you need to prevent your pet from doing,'' says Steve Hansen, veterinary toxicologist and director of the ASPCA Animal Poison Control Center. ``However, we do recommend homeowners or even people who walk their dogs in public parks to keep pets off of treated lawns until sprays have dried or dust has settled. Typically 24 hours is adequate.''