Why Does Dog Urine Burn Lawns and What You Can Do About It

For many homeowners or renters, maintaining a lush, green lawn is a labor of love and is often made more difficult if they have dogs – from digging and wearing out paths in the grass to peeing and scorching it with their urine.

A dog has to pee, and they often go in the same area, which can be problematic.

So, why does dog urine burn lawns and harm some plants? All fingers point to nitrogen. The culprit isn't the pH balance in your dog's urine, as most people would think.

Read on for tips on how to keep your lawn green and why buying a "green grass" supplement that professes it'll change your dog's urine and not cause brown spots isn't worth the money – and it could actually harm your dog.

Don’t Blame the Urine pH for Scorched Grass

Many people have thought that the pH of dog urine was the issue. But dog urine ranges from 6.0–7.5, and most grasses can do just fine pH from 5.5–8.0.

The dog supplements sold to prevent grass damage have ingredients to change the urine pH. This will have no effect on grass scorching since pH is not the cause of urine damage to lawns.

Read more below about the problem with 'green grass' supplements and their ingredients.

The Nitrogen in Dog Urine Burns the Grass

Dogs eat lots of meat, which is made of protein. Protein contains nitrogen. Nitrogen waste is broken down and passed out through feces and the kidneys (which make urine).

Urine is primarily made up of water and urea and has a high nitrogen concentration. Normally, plants love nitrogen, but even plants can get too much of a good thing.

You may notice that the urine spots in a lawn have a bright green border with a dead grass center. The bright green border comes from the fertilizing effect of the nitrogen in the urine at the edges.

However, the high concentration of nitrogen at the center has burned the grass leaves, causing them to die.

Nitrogen in dogs' urine is normal. However, certain illnesses can increase the nitrogen level in the urine, and you may see more browning on the lawn.

Causes of Increased Nitrogen in a Dog’s Urine

• Dehydration (more concentrated urine)

• Urinary tract or genital infection (more cells in the urine)

• Stones in the urinary tract (more inflammatory cells in the urine)

• Blood in the urine (more cells in the urine)

• Protein-losing nephropathy (protein loss from the kidney)

• Cancer (more cells in the urine or protein loss from the kidney)

Do Female Dogs Cause More Brown Spots on Grass than Male Dogs?

As mentioned above, nitrogen causes grass scalding. The nitrogen levels in female and male urine are the same. However, each dog is unique, and a medical condition or dehydration could mean their nitrogen levels are higher, but gender does not play a role.

Female dogs may leave more urine scalds on the lawn since they tend to pee in one large spot on the ground. Male dogs are more likely to pee on vertical surfaces (marking trees, rocks, or anything else that any other dog peed on recently).

However, this pattern is not true for all dogs. Younger and older male dogs will squat to pee, while some males squat lifelong. My own female dog marks vertically when she pees, and she rarely leaves a large amount in one place.

Do Dog Supplements Work to Protect Your Lawn?

For the most part, the answer is a big No. Why?

• Adjusting the urine pH does not work to prevent grass scorching and may harm your dog. See the information on Methionine below.
  
  
• Currently, there is no known way to remove nitrogen from the urine of healthy dogs.
  
  
• There is very little peer-reviewed science to back the mixture of the chosen ingredients together.

The Most Common Ingredients in Grass-Saver Supplements

Grass-saver supplements have several themes for their ingredients: removing Nitrogen, adjusting the urinary pH, preventing urinary tract infections or urinary stones, and pro- and post-biotics.

Yucca

This looks to be the most helpful ingredient.

Yucca schidigera extract: This ingredient is only one of the ingredients that has been studied in dogs rather than people! It decreases the amount of ammonia (which includes nitrogen) in feces.

It may also reduce intestinal gas and the smell of feces.

Remember pH is not the cause of dead grass! So, a supplement that claims to adjust it is a waste of money.

Methionine or DL-Methionine

This is an essential amino acid (meaning that cats and dogs need it to survive) and is a building block for proteins. It is used in the necessary amounts in pet foods, so normal dogs should not need extra amounts of methionine.

Veterinarians may prescribe additional amounts of methionine (that is, prescription strength) for dogs or cats with struvite urinary stones to help acidify the urine.

Methionine should not be used in any dog who has:

• Urine pH over 6.5
• History of kidney failure
• Liver disease
• Pancreatic disease
• Any disease causing acidosis (such as Diabetes mellitus, Renal Tubular Acidosis, and Addison's Disease)
• Calcium oxalate or Urate stones
• Been eating an acidifying urinary diet

These warnings are a big concern since many pet parents will start their dogs on a supplement without first having a veterinary examination or lab work done to determine whether it is safe for their dog.

Vomiting is a common side effect of methionine. Methionine also negatively interacts with many medications, including:

• Acetazolamide
• Amikacin
• Colchicine
• Bismuth Salicylate (Pepto Bismol®)
• Erythromycin
• Gentamicin
• Mexiletine
• Phenylpropanolamine (PPA or Proin®)
• Potassium Citrate
• Zonisamide

Cranberry extract, concentrate, or fiber

Cranberry has been used by women for years to prevent E. coli urinary tract infections. A few peer-reviewed studies in dogs suggest that cranberry extract reduces E. coli attachment to dog urinary cells and may reduce the number of urinary tract infections in dogs with a history of recurrent urinary tract infections.

This effect has not been shown with other types of bacteria. No peer-reviewed studies have been performed to see if cranberry extract prevents grass scalding.

D-Mannose

D-mannose is a sugar that also prevents bacteria from sticking to urinary cells. While there are studies on this supplement for humans, no studies have been performed on its effectiveness in preventing urinary tract infections in dogs. It is often combined in supplements with cranberry.

D-mannose is very safe and will likely do no harm. But its effectiveness for grass scalding, along with cranberry, is unknown.

Apple Cider Vinegar

Apple cider vinegar is used by human beings around the world for a variety of ailments, one of which is to prevent or treat urinary tract infections and kidney stones.

However, there are no peer-reviewed scientific studies in people or dogs showing that drinking small amounts of apple cider vinegar can adjust or prevent urinary tract infections, urinary crystals, or urinary stones.

Brewer’s Yeast

This is a common ingredient in pet foods and supplements. It is a "postbiotic,” meaning the yeast still has benefits even after it is inactivated. It contains amino acids and B vitamins. It is yummy for dogs and is most likely added to increase the supplement's taste.

Proteolytic Enzymes

Proteolytic means breaking apart proteins. Dogs have many proteolytic enzymes in their intestines, which they use every time they eat food. These enzymes break apart proteins so that dogs can digest proteins.

Unfortunately, giving a dog extra enzymes does not remove any nitrogen from their urine or feces. The nitrogen is still there in the form of amino acids, the building blocks of protein.

Enzymes available as supplements might include:

• Protease
• Amylase
• Lipase
• Pancreatin
• Cellulase
• Hemicellulase
• Papain
• Bromelain

B Vitamins

There is very little data on vitamins and their effect on nitrogen reduction in dogs.

Studies in humans have examined whether low or high vitamin B6 levels are associated with oxalate kidney stones.

The research has been conflicting on this; even a very large study of 289,659 people had differing results between men and women. There have been no dog studies on B vitamins in preventing urinary stones or urinary tract infections.

Fortunately, B vitamins are very safe because any extra B vitamins are sent out via the urine instead of becoming toxic. But if you're supplementing with too much, then you're wasting your money.

How to Find a Quality Dog Supplement

If you decide that your dog needs a supplement, look for one certified by the National Animal Supplement Council (NASC). In the United States, the FDA does not regulate the supplement industry, which means there are no regulations for the quality control of supplements.

Supplements are regulated as food products, not as medications.

Quality supplement manufacturers voluntarily submit to NASC’s quality control protocols, random testing, and annual testing. These manufacturers can then carry the NASC seal on their products and websites.

Do Dog Rocks Work for Saving Your Lawn?

No summary of grass scorching would be complete without mentioning Dog Rocks. These rocks come from Australia, and dog parents dealing with grass scorching add these to their dog’s drinking water.

If your dog has multiple water bowls, you need to add them to each bowl, or the Dog Rocks website states that the rocks will not work.

Their marketing states that it prevents grass scalding through the paramagnetic* removal of nitrates, a specific combination of nitrogen and oxygen.

Keep in mind that dogs get their nitrogen from food, not water. Nitrates are infrequently found in water unless it is contaminated by fertilizer or wastewater.

While these rocks placed in the water are unlikely to harm dogs (unless swallowed or chewed on!), will the nitrogen and oxygen they absorb be enough to reduce the scalding of your grass? I am honestly not sure.

*If you want to know what “paramagnetic” is, you are not alone! I had to look that one up myself. A compound or molecule with an unpaired electron can be paramagnetic, that is weakly attracted to a strong magnet.

This means that if there are any nitrate (NO3-) molecules present in the water, nitrate molecules stick to the Dog Rocks in the water bowl.

But it will not work for any other potential nitrogen sources in the water or for any food or water that your dog eats away from the Dog Rocks bowl.

A few years ago, another veterinarian on our team reached out with questions for the manufacturer, but we never heard back.

If You Notice a Sudden Increase or Appearance of Brown Spots on Your Lawn

The first thing to ask yourself is if the change is due to your dog or the lawn.

Always look to your dog first because new spots may indicate a change in your dog's health!

• Is your dog drinking and peeing more than last week or last month?

• Is your dog asking to go out more frequently?

• Has your dog had any urinary accidents in the home?

• Has your dog been licking their vulva or penis?

• Has your dog been eating less recently — leaving food behind in the bowl or only eating treats?

• Does your dog have a reduced energy level — taking more or longer naps, going slower on walks, or acting less playful?

Drinking more and peeing more could be signs of a urinary tract infection, kidney disease, Diabetes mellitus, Lyme disease, Cushing’s disease (an overactive adrenal gland), increased blood calcium, or even cancer.

Asking to go out more frequently, peeing in more spots when outside, licking the vulva or penis, pain when urinating, or blood in the urine may be signs of a urinary tract infection.

A reduced appetite or energy level, especially if it is persistent or seen with any of the other signs, is concerning.

It is always best to play it safe and have your vet check your dog and their urine if you see any potential signs of illness. If you need to provide a sample, here's how to collect your dog's urine and how soon before your appointment you need to collect it.

How to Prevent Grass Scorching by Dogs

Provide upright surfaces, such as a fake hydrant or some big rocks for male dogs.

Many dogs learn to go to the bathroom on a particular surface type, and it can be difficult to switch for adult dogs. If your dog needs a grass area for pottying, it's easier to choose a particular area of the yard as their designated potty spot rather than try to retrain them to go on a different surface.

ake the time to make it visually obvious for your dog that it's a "separate" area, such as with garden fencing.

Or consider setting up a Fresh Patch on top of the new gravel or mulch area and taking your dog on a leash to relieve themselves there to build a new habit. Every time they go potty there, give them a treat and praise!

Over time, you can reduce the size of the grass patch and your dog should become more comfortable going on a different surface.

Safety note about mulch: While most mulch is safe, cocoa bean mulch is not. When warmed in the sun, the cocoa bean shells contain theobromine and caffeine. Theobromine is what makes chocolate toxic for dogs.

Dogs, just like people, are drawn to the aroma of this mulch, and they tend to want to eat it.

Adding water to food, feeding more canned food, adding ice cubes to the water bowl in cool weather, and providing a water fountain option in addition to water bowls are all ways to help your dog consume more water daily.

If your dog drinks more, their urine will become more dilute, and then it will be less likely to scorch the grass.

Recognizing Signs of Urinary Tract Infections

Dogs with urinary tract infections urinate more which could cause more lawn scorching spots.

Signs of a urinary tract infection include:

• Urinating more frequently
• Urinating in many different spots
• Pain or discomfort during urination
• Possible blood in the urine
  
  

If your dog has an issue with urinary tract infections that keep returning, your veterinarian can check for any underlying conditions that are causing the infections to come back.

If a cranberry supplement is indicated, your veterinarian may recommend a supplement or see our article for an appropriate supplement.

Keep in mind that the grass-saving supplements may have additional ingredients that may not be ideal for your dog’s condition. When your dog is sick, stick with a specific supplement designed for their health condition.

Supplementing With Probiotics

You can help your dog produce less nitrogen by keeping their intestines healthy.

Probiotics can improve digestion, reduce diarrhea, and even enhance the function of the immune system. There is evidence that probiotics can reduce the need for antibiotic use in women who have frequent urinary tract infections.

However, there are no studies on this in dogs yet.

Probiotics are common ingredients in grass-saver supplements. Adding probiotics to your dog's diet can help them have fewer episodes of diarrhea, which will reduce the amount of nitrogen and feces on the lawn.

Diarrhea episodes can lead to secondary urinary tract infections, and then more frequent urination, so the probiotic ingredients could be useful. We have a list of vet-recommended probiotics.

Helping Your Scorched Lawn

Depending on the type of grass that you have, you may be able to re-seed scorched areas or place sod in that area during growing seasons.

Grass spread by runners may fill the area over time once the dead grass has been removed. It is best to consult an expert to determine how to help your lawn return to a lush green carpet.

Fescue is more resistant to urine damage if it grows in your area. Free help is often available from county and state extension offices or consult a lawn maintenance service.

Just don't let it grow too tall between mowing, as the grass seed awns pose a risk to your dog.

If your lawn is suffering because of your dog, set up an elimination spot and consider reaching out to your vet for an exam and urinalysis to ensure that a medical issue is not the underlying cause.

When considering a grass-saving supplement for your dog, remember the motto, “First, do no harm.” Why give your dog a supplement when science does not back it up?