| OCR Text |
Show THE OGDEN VALLEY NEWS Volume IV, Issue V Page 21 June 15, 2001 Xeriscapes Using More, Not Less, Water Study Confirms People, Not Plants, Waste Water By TPI, Turf Producer International Xeriscape, a word coined and later trademarked by the Denver Water Department, to designate water-conserving landscapes is not living up to its promise according to on-going research at Arizona State University (ASU). While xeriscaping has been touted as a way for homeowners to receive a bounty for replacing their lawns by converting to native plants and use 50 percent less water, just the opposite is taking place. At least in Phoenix and Tempe, xeric landscapes are receiving even more water than traditional landscapes. ASU horticulture professor Dr. Chris Martin reports, “xeriscapes in Phoenix and Tempe, on average, received at least 10% more water than traditional landscapes consisting of turf and other so-called ‘high wateruse’ plants. Xeriscape water use has been consistently higher than traditional landscapes and this is even more startling when we considered that the traditional or ‘mesic’ landscapes have on average 2.6 times more foliar canopy per yard than the xeriscapes.” Confirming what the turfgrass industry has been saying for years, Dr. Martin found that the water-wasting “culprit” was not the plants, but the people. Funded by a long-term grant from the U.S. Environmental Protection Agency (USEPA), the ASU study began measuring and monitoring landscape water use in 1998 by first retro-fitting landscape irrigation systems with specialized water meters. For the study, a total of 18 homes were selected in Tempe and Phoenix because of their similar age, value and appearance and because of their distinct landscape differences, half being xeriscape and half being mesiscape. A stunning example from the study involves two similar, well-done xeriscape homes without any turf, on the same street in Phoenix, with similar sized front yards (2,086 vs. 2,096 ft2). One homeowner applied an annual total of 30,000 gallons of water, while the other used a remarkable 247,000 gallons! Dr. Martin said, “Though these households had wildly disparate landscape irrigation practices, there was no resultant measurable or visible difference in plant appearance or fitness.” In a follow-up survey of homeowners with xeric or mesic landscapes, Dr. Martin and his research team found that most residents recognize the importance of water conservation, but generally do not want a strictly “desert” appearance in their yard. They prefer an “oasis” setting. The survey also documented that the homeowners were not aware of how much water they were applying to their landscapes, or how often they should apply water. After reviewing the ASU findings, Doug Fender, executive director of the not-for-profit Turf Resource Center, said, “everyone who makes their living in the green industry, as well as water agencies needs to do a better job of educating people about plant water requirements and watering. This study clearly documents that desert or native plants are not water-saving plants by themselves. It’s the well-intentioned, but illinformed homeowner who wastes water, whether it’s a desert plant or a grass plant.” He concluded, “Turfgrass can be maintained with a lot less water then most people give it and many scientists have noted that more lawns are killed with too much water than too little. We should encourage people to accept dormant lawns in the height of summer. Just on-quarter inch of water every four to six weeks will keep grass plants alive and ready to green-up when temperatures cool and rainfall returns or peak water demands have passed. We can conserve water and have beautiful and balanced landscapes.” Insect Attacks Trees An insect called the Ips bark beetle is making its presence known in the bench areas along the Wasatch Front. The beetle attacks spruce and pine trees eventually killing them. “In a normal year the beetle will take flight in mid-April to attack a new host tree,” explained Colleen Keyes, forest health coordinator for the Utah Division of Forestry, Fire and State Lands. “While a healthy tree can usually fight off the invader, a tree under stress is very susceptible to invasion. “Luckily there are some things a homeowner can do to prevent damage to landscaping provided the tree is not heavily infested,” she added. “Spraying with a registered insecticide that contains the chemical Carbaryl will usually protect the tree from attack or reduce damage.” Carbaryl is found in several commercial insecticides, which can be found in home and garden stores, and is effective for about one year. However the insecticides are most effective when sprayed with a highpressure sprayer with a car wash type nozzle, and it is important that the entire tree be well drenched. Proper watering of trees will also help maintain health and enable the tree itself to ward off the invader. |
