If you're a dog owner, the greening up of your lawn this spring will likely coincide with the emergence of burn spots where your four-legged friend relieves itself. In extreme cases, these spots, which are caused by the nitrogen in urine, can grow large enough to require reseeding. That's resulted in a cottage industry of dietary doggie supplements designed to neutralize nitrogen and prevent burns. Do they do the trick?

Consumer Reports hasn't tested any of the supplements, but we checked in with Sarah Abood, a small-animal clinical nutritionist and assistant dean at the Michigan State University College of Veterinary Medicine. "If there is appropriate scientific evidence in support of nutritional supplements to 'treat' urine stains on grass, I am not aware of it in the literature," Abood said in an e-mail.

We also checked in with several turf-grass scientists from around the country. While some reported anecdotal evidence of supplemental success, the consensus was that the surest way to eliminate burns is to pour a bucket of water onto the urine right after your dog goes. That's a lot of work, not to mention a waste of water. A better, albeit more challenging, solution is to train your dog to go in a designated area of the yard. Providing a marking post, such as a bird bath or lawn ornament, might help with the process.

You could also try to dilute your dog's urine before it leaves its body, for example by feeding them canned food or moistening dry food with water. Adding a pinch of salt will also encourage them to drink more water, though this can cause problems for dogs with kidney or heart conditions. That's why you should always consult your veterinarian before attempting any home remedies.

At Consumer Reports we've been thinking a lot about lawns lately as we prepare for the next mowing season with new mower tests and other lawn care tips.