Science in Action: Las Vegas – Making the Desert Bloom

Corrosion to sidewalk from salts

            It is the soil. The soils in Las
Vegas are among the worst of any major city in the world. Native desert soils
have salt levels 25 times higher than most Extension Services would consider
safe. Boron levels, where one ppm can be considered lethal for many plants, can
exceed 40 ppm in isolated pockets designated for development. With pH levels
often over 8.5, sodium  and caliche change
the soils so much that they require picks or jack hammers for planting. Las
Vegas soils are frequently very high in gypsum. The gypsum levels are so high
that there are two gypsum wall board plants in the area. The sulfates contained
in gypsum can be extremely damaging to unprotected steel and concrete. Water
has been cheap in Las Vegas in the past. This, combined with the efforts to
promote tourism and gaming here, has created an artificial, desert rainforest
in the urban areas. The highly soluble gypsum has dissolved in these irrigated
desert soils, leaving voids that are filled by collapsing soils that damage
walls, foundations, roads and structures. The Colorado River water used for
irrigating in Las Vegas contains one ton of salts per acre foot. What does that
mean to residents? A normal lawn irrigated in Las Vegas will receive about 600
pounds of salt each year.

Salt damage to block walls due to salt in soil and water

            Even with its problems, the
gardening season in Las Vegas extends through most of the year. The heaviest
planting season is in the spring but fall planting is a regular and growing
practice with Las Vegas residents. Most major nurseries like the string of Star
and Plant World nurseries operate throughout the year with some seasonal sales during
the slow months at Christmas. There are essentially no wholesale growers in
southern Nevada. In fact, there has never been an attempt at wholesale growing
since the population and growth spurt after 1984. Currently, Las Vegas is a
retail market in nursery goods with wholesalers from the surrounding states.
Major plant sales are through direct sales or plant brokers. The use of color
in business complexes, hotels and wholesaling to mass merchandisers like
Wal-Mart, Kmart, Target, Home Depot and Builder’s Square and nurseries is big
in Las Vegas with the dollars all going out-of-state. Yet publications and syndicated
talk shows claim that Nevada is the number one state in which to establish a new
business.

Las Vegas Valley Water District Desert Landscape Award Winner

            Las Vegas is a service-oriented
town. The 4 – 6,000 people who moved to the area each month until a few years ago come here with the
expectations of a 24 hour town and having a good time. Many want the freedom
that service companies provide to avoid the heat and have the time to enjoy a
24 hour town. Rough estimates of the percentage of residents using lawn
maintenance companies would put it at about 10 percent. The traditional
grass/tree/shrub landscapes are becoming a thing of the past because of
increasing water costs and environmental awareness. Because of a heightened
awareness in conserving water and sensitivity to the desert environment, there
has been a growing trend toward a dry-type of landscaping. Desert-adapted
plants and examples of the Sonoran desert landscape “feel” have been becoming
more attractive to new residents. This has presented installation and
maintenance problems to old time landscapers who “grew up” with the old Las
Vegas mentality of “keep it green” and “green side up”.

TPC one of the desert southwest courses

            Horticulture in Las Vegas is big
business. And like the craps tables, it can be in one big throw. Approximately
5 percent of a hotel’s construction and material costs are in landscaping. This
doesn’t take a genius to figure out that a billion dollar megaresort owns a
good-sized nursery when it’s completed.  A
few years ago the gardening done in the hotels were done by a small union crew
out of the Engineering department. The whole operation would be overseen by the
Director of Operations. Because of the high degree of technology now involved
in gardening at these megaresorts, one or several full-time, experienced
horticulturists are required to oversee work crews. Because of recent water
mandates, water used in interiorscapes is recirculated with state-of-the-art
technology. Close approximation of guests with the landscape fosters interest
in IPM  (integrated pest management) technology.
One hotel’s horticulture budget and staff can be equivalent to an 18 or 36 hole
golf course’s. With occupancy rates averaging over 80 percent, gaming money
from guests keep these budgets fueled. Interiorscapes and the use of foliage
plants and exotics is becoming more popular in a competitive attempt to attract
guests and their business. With these types of businesses, gardening in Las
Vegas, like gaming, is truly year round.

Research at Univ of Nv on salt damage to plants

            The number of golf courses in the
Las Vegas area has doubled in the last ten years. Ten years ago, surveys of the
industry reported that over ten percent of the visitors to Las Vegas came primarily
to play golf. It was difficult to schedule a game since many of the courses had
low greens fees and averaged nearly 300 rounds per day. The golf course
industry exploded here in 1984, about the same time the population began its unpredicted
climb. Golf course developer’s greatest problem was water and who was going to
get it first. Over fifty percent of a golf course’s budget is now accounted for
by water. The rights to effluent water is now fought over. Nuisance water,  pumped from an underground parking lot at a
major resort just across the street from a golf course, used to be dumped into
the county’s sewer lines. Now it’s considered a resource and research is
underway to use it for turfgrass irrigations.