This lawn problem has nothing to do with fungi, bacteria, or insects, and everything to do with man's best friend. It isn't pretty, but we've all seen it--brown, dead spots surrounded by lush, green grass, caused by dogs urinating and defecating.
While cleaning up doggy droppings isn't pleasant, at least it's possible; urine poses another problem altogether. Its volume and high concentration of nitrogen cause the grass to burn and die. This is particularly evident with female dogs that squat to urinate, concentrating their urine in a small area. Although male dogs' urine is equally caustic, they distribute it over a wider area.
Once you have identified the culprit, the obvious solution is to keep it from urinating on the lawn, either by physical barrier or training. But obvious isn't always simple, which is why some pet owners have tried other techniques, such as repellent sprays and even dietary supplements. Though they seem promising, neither works.
Repellents may actually encourage more peeing as dogs try to overmark the unfamiliar smell. And dietary supplements may have detrimental, long-term health effects on pets.
Nevertheless, there are ways to lessen the impact on your grass. Veterinarians in Colorado have shown some grass types are less likely to be burned by high concentrations of urine. Tall fescue and perennial ryegrass are more resistant than bluegrass and Bermuda. Keeping the grass in top health reduces the permanent damage and speeds the lawn's recovery. Diluting the spot with water 5 to 10 minutes after dogs pee saves the grass, but it's impossible to be that vigilant.
Or if you can simply accept the reality of a few dead spots, repair them by first soaking the area with water. Rake to remove dead grass and to scratch soil, and either plug in a section of the same type of sod, or overseed.
Charlie Nardozzi is an award winning, nationally recognized garden writer, speaker, radio, and television personality. He has worked for more than 30 years bringing expert gardening information to home gardeners through radio, television, talks, tours, on-line, and the printed page. Charlie delights in making gardening information simple, easy, fun and accessible to everyone. He's the author of 6 books, has three radio shows in New England and a TV show. He leads Garden Tours around the world and consults with organizations and companies about gardening programs. See more about him at Gardening With Charlie.
