When the Southern Nevada Water Authority's turf conversion program started in 1999, I was on board with the idea. I was a true believer, an environmentalist and conservationist who'd proudly served for many years as lead groundskeeper at its partner agency, the Las Vegas Valley Water District.

The rationale behind the Water Smart Landscapes rebate program was valid: There was simply too much grass that served little to no purpose in Southern Nevada. Much of it was irrigated inefficiently, especially on highly sloped surfaces that caused a huge amount of runoff and water waste. I strongly believed then — and still do now — that a desert landscape is far more beautiful than a boring lawn.

The water authority's cash-for-grass incentive started off paying people 50 cents per square foot of grass removed from their yards. It later increased to $1, and it's risen to roughly $7 per square foot today. (For its part, the water district contributes to the incentives by discouraging lawns through excessive use charges — without necessarily considering factors such as property size, number of residents or existing vegetation, but that's another subject.)

But perhaps the biggest incentive will come into play when a wide ban on irrigating "nonfunctional turf" from our taps, AB356, takes effect in 2027. In the water authority's war on grass, this could be the decisive battle. (Disclosure: I gave a sworn declaration in an active lawsuit challenging the water authority's enforcement of this ban, but I am not a plaintiff.)

If only it were that simple. There's a problem with this all-grass-is-bad thinking: It doesn't consider our trees, which in many cases are dependent on grass.

You see, Las Vegas, like much of the rest of the country, has been installing — and obsessing over — lawns since the 1950s.

And like it or not, that means lawns have become part of our urban environment. Naturally, thousands of trees have been planted in or near our long-established lawns and have grown accustomed to consistent watering and cooler conditions. Over time, the trees have matured into large, established specimens that contribute far more environmental value than the lawn.

Many people assume that replacing their lawn with a more drought-tolerant yard is always a good choice. However, depending on the type and health of the existing landscape, sometimes it's wiser to wait until the trees that depend on that lawn complete their natural lifespan. Trees are one of the most important factors in mitigating the urban heat island effect, and their relationship to the landscape — whether it's xeriscaped or turf heavy — is complex.

I'm frequently consulted by clients after they've removed their grass. Often, homeowners are heartbroken because their beloved trees are in severe decline or have already died. They tell me that if they had known the effect on their trees would be so devastating, they never would have removed the lawn.

The reality is that the conversion process, even when done carefully, can be very disruptive to a tree's root system. It also significantly alters the wetting pattern and water supply that the tree has relied on for decades. Some tree species are remarkably resilient during this process. However, more temperamental species and older trees are easily pushed into decline and, ultimately, death by the stresses of turf conversion.

How do we measure the economic loss from the decline and death of possibly tens of thousands of mature trees — reduced property values, increased energy consumption as our homes lose shade, shorter lifespans for air-conditioning systems forced to work harder? How do we measure its effect on our quality of life?

Part of my frustration with the water authority is that it claims to educate people on how to do turf conversions properly. The information it imparts is technically correct, but falls far short of the depth and nuance needed to understand the plant health care that's involved.

Additionally, most of the turf removal work in Southern Nevada is performed by landscape contractors. The authority's Water Smart Landscaper program may give customers a false sense of security that the people performing the work truly understand the complexities involved. The certification requires only six nominal hours of water efficiency training, and much of that time is spent discussing the water crisis and the Colorado River. The remaining portion focuses largely on drip irrigation, much of which doesn't relate directly to tree health at all. I know this because I've taken the course.

And if all that wasn't enough, the authority's rebate program rewards people for installing artificial turf — which I consider nothing less than a carpet of toxic plastic. Frankly, if someone chose to pave the same area instead, it would be less environmentally damaging for two reasons: heat and harmful chemicals.

Artificial turf gets hot. It raises temperatures not only for nearby plants but also for the property itself and possibly the city as a whole. During the summer of 2024 — Las Vegas' hottest summer on record — I bought a point-and-shoot thermometer to measure surface temperatures. On days when the air temperature was around 105 to 107 degrees, I found that in full midday or afternoon sun, concrete and rock mulch typically measured around 155 degrees. Asphalt measured around 165 degrees.

Artificial turf consistently measured about 10 degrees hotter than asphalt — around 175 degrees. That additional heat load could be devastating for surrounding plant, animal and even human life.

Artificial turf also harms the soil ecosystem beneath it. The microorganisms that naturally develop in healthy soil are killed off. Healthy, living soils that have developed over decades are turned into a wasteland. Moreover, artificial turf contains known carcinogens, neurotoxicants, endocrine disruptors and pulmonary irritants. Over time, it can break down into microplastics and nanoplastics that can carry those carcinogenic "forever chemicals" into our bodies.

I predict that artificial turf will one day be viewed the same way we now view asbestos or lead paint. Yet we're installing enormous amounts of it across the valley — on sports fields, residential yards, municipal projects and Clark County School District campuses. At the very least, the water authority should prohibit the use of artificial turf in the rebate program.

Water is a valuable resource that deserves protection and requires responsible use. Everyone agrees with that. But our water agencies have a responsibility to lead this vital effort thoughtfully and transparently — and without damaging our economy, environment, health and quality of life.

Trees and grass help keep us cool, delight our senses and connect us to nature. We live in a desert, but we must act reasonably and responsibly to make it the desert oasis we want and deserve.

Norm Schilling is a longtime desert horticulturist in the Las Vegas Valley and president of Schilling Horticulture and Mojave Bloom Nursery.