There are a combination of reasons for my interest in this subject. First, as acknowledged in Michael Pollan's book, grass is everywhere, thanks to Humans. We grow it in great quantity, care for it, give it everything it could possibly need. Or, at least, that is the ideal for a lawn. Its evolution is linked directly to ours, initially by our consumption of grass-eating animals and later by our consumption of the Cereals (corn, wheat, barley, rye, et cetera).
Thus, by my reasoning, the evolutionary scheme of lawn grass has been designed, in part, to cope with the stresses placed upon it by Human-related beings. In recent years, these demands have changed, somewhat, and I begin to wonder where in evolutionary lines today's grass stands -- whether it is developed for the needs of the modern lawn or whether it is still evolving to meet those standards. Some of these stresses (herbicides, for instance), are quite new to our lawns, and are causing problems for both grass and Humans that have yet to be fully recognised. For instance, Poo from All Over Creation got sick from eating dirt in the graveyard (eating dirt is something that most babies do on occasion), and yet Cass did not even suspect the ingestion of synthetic chemicals even though she knew that Poo had been lawn-munching. These agricultural* changes have been implemented so fast, and on the whole people know so little about them, that there has been difficulty even in thinking appropriately about the stuff. Grass seems so friendly, so harmless.
And yet, on the other side of the picture, many of the older survival needs of the grass still hold true, today . . . albeit in a form that some of us might not reconise. In The Omnivore's Dilemma, Pollan mentions grazing (now routinely performed by lawnmowers) and the benefits of nitrogen-rich cow manure (supplanted by synthetic and natural fertiilizers, alike, but almost always sans bœuf). The most basic requirements for life (water, sunlight, fertile soil) are still present as always, though the soil is less dependable, perhaps, than it once was.
But what of urine? Apparently, it is common knowledge for people who own large dogs that dog urine -- especially female dog urine -- is extremely acidic and eats away at the grass causing what is known as 'lawn burn'. In my lawn at home, however, I have long noticed that where my dog urinates, the lawn is infinitely greener, and the pH of my lawn is fairly acidic, already. Which is enough to raise my eyebrows. . . .
Looking online, I found several sites, initially, that support the notion that the acid in urine kills grass, but many of the more credible sources pointed in a different direction. It turns out that dog urine, while highly acidic, is also extremely rich in nitrogen, which in small amounts creates a fertilizing effect. However, in great quantities or highly concentrated amounts (and especially on fertilized grass), the recipient plant an 'overdose' of liquid N, causing it to burn in a manner similar to any other kind of fertilizer overdose. The telltale sign of a urine-caused lawn burn is a 'puddle' of brown grass surrounded by especially tall green grass where the nitrogen became diluted enough to benefit rather than harm the grass.
Part of the reason I am sharing this is because there is a market, now, for urine-related yard problems. Sometimes, this involves marketing certain kinds of grass (especially fescue and perennial ryegrass) as more urine-resistant than others. However, there is also a sizable market for 'dietary' fixes, most of which are intended to lower the protein content of the dog's food and thus decrease the acid content of their urine, when acid is not, in fact, the main problem. This is extremely worrisome because so many people have dogs, and we have already seen what the pH changes in livestock have done for Human health (not to mention the health of the livestock).
But what, then, can be done to deal with these lawn problems? First, to look at the choice of dog. This is my dog, Kashi. She is half Shih Tzu, half Toy Poodle -- a mix sometimes lovingly dubbed the Shit Poo.
Because she is so small, she does not issue the same quantity of urine as, say, a Newfoundland. Moreover, she is a very fussy pisser, and is in the habit of marking her territory more than once whenever she has the opportunity (for instance, when we are going on walks). Between these two conveniences, my lawn is at an infinite advantage. Male dogs also create less havoc on their surroundings, for their habit of marking standing objects such as bushes is less disruptive, aesthetically, than a big patch of brown in the middle of the lawn caused by a female squatter. However, ultimately, it is a matter of repetition. If that male dog marks the same bush every morning, the bush is likely to suffer. If any dog is confined to 'doing his business' in a certain part of the yard, that part of the yard is likely to get too many Nitrogen deposits in one area. Most sites recommended varying the dog's potty routine or, alternately, creating a non-grass area for the dog to use for these purposes.
The other frequent suggestion was to douse the area with water within nine hours of urination. This apparently works well, though I would caution anyone taking this advice to try to do this in the morning and the evening if they do not want the sun scorching their grass, which is at its most fragile when wetted.
Two important variables were not properly addressed by any of the sites I went to. The first of these is whether the use of fertilizer contributed to the lawn burns -- whether, for instance, a dog which might benefit a lightly fertilized lawn might harm a heavily fertilized one. The second variable is the land itself. Looking down on my back-yard from the balcony, in summer, it is very apparent where Kashi has done her business, because there are tufts of grass about the lawn which coincide exactly with her piddle-habits (I know this because several years ago I was curious and marked the places she went in the backyard). Our front yard bears no such distinctive tufts, but softer, more general patterns. The difference between these two places? My backyard is more or less flat, whereas my entire front yard lies on a hill. If the pitch of the land can alter how the nitrogen in my dog's urine is dispersed, I imagine it would disperse a larger dog's urine, as well, thus benefitting rather than harming the lawn.
* The raising of grass was originally an agricultural activity, intended primarily for the nourishment of livestock.
Various Sources **
- Seefeldt
- Thompson
- Fuller
- Glover
- West
- Berkeley Parents Network
** These sources were chosen for their immediate availability on Google and thus representative of some of the most readily accessible public information on the topic.
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