Page 8 - the NOISE November 2012
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NEWSFEATURE
TAXONOMY of a Ponderosa Pine and Groundsel (Ragwort); SWCA’s modeling of wind-blown distribution of reclaimed wastewater throughout critical habitat.
PONDEROSA PINES, THE PEAKS GROUNDSEL & THE SMOKING GUN
BY CHARLES SEIVERD
If a tree starves in the forest, will anyone hear it? Or, perhaps to ask the question more precisely: if a Ponderosa Pine starves on top of the San Francisco Peaks from the unnatural elemental compounds in re- claimed wastewater, can anyone save it? With sprayguns poised to spritz reclaimed wastewater as artificial snow on the San Francisco Peaks less than a month from now, more questions than answers persist as to the safety and environmental benefits of the practice approved by the Arizona Depart- ment of Environmental Quality, the City of Flagstaff, and the United States Forest Service.
Since the last article in this series, a study by Colorado State University document- ing reclaimed wastewater’s effects on Pon- derosa Pine trees has been unearthed, the Arizona Daily Sun has reported on the “purple pipe mutating bacteria” found within spray- heads of the substance, and the Hopi Tribe continues to pursue consultation with the Department of the Interior and Secretary Ken Salazar on new information about the Federally-Threatened Groundsel, which grows only on the San Francisco Peaks.
Just as is observed at Continental Coun- try Club in Flagstaff — which has been irri- gating with reclaimed wastewater for what is perhaps longer than any other golf course in the nation, at 36 years — researchers in Colo- rado began noticing needle burn and decay from parks and golf courses in the Denver area in 2005. In a study commissioned by Colorado State University at Fort Collins, a team of horticulturists inspected Ponderosa Pines at three golf courses and one city park irrigated exclusively with reclaimed waste- water between 5 and 20 years, and com- pared them with three golf courses and one city park using only ditch water.
In their methods, the team randomly se- lected trees from each of the locations, all similar in soil composition, landscape man- agement regimes, and plant species; using the sites irrigated with ditch water as con- trols. Each of the test sites were fertilized with 75 kilograms of Nitrogen per hectare and received 26 inches of reclaimed waste- water annually. Each of the control sites were fertilized with 150 kg/ha N and received 22 inches of ditch water annually. The differ- ence in Nitrogen treatment corresponds to industry standards when using reclaimed wastewater, which already has a higher Ni- trogen content.
In addition to a visual evaluation, “the sampled Ponderosa Pine branchlets were brought to the lab and needles separated to different age groups,” according to the study.
“One- and 3-year old needles were selected for ion analysis. To measure ion concentra- tions, needles were rinsed with deionized water to remove possible contaminations from the surface and dried at 158° F for 24 hours. Dried needles were ground in a Wiley mill to pass through a screen ... Approximate- ly 1 gram of screened and dried sample were weighed and ashed for 7 hours at 932° F. Ash was dissolved in 10 milliliters of Hydrochloric
Acid and diluted with deionized water. So- lution aliquots were analyzed for Sodium, Potassium, Calcium, Magnesium, and Boron, and other metals by inductively-coupled plasma atomic emission spectrophotometry.”
The study concluded that “Ponderosa Pines grown on sites irrigated exclusively with reclaimed wastewater exhibited 10 times higher needle burn symptoms than those grown on sites with surface water. Tissue analysis indicated that Ponderosa Pine needles collected from sites receiving reclaimed wastewater exhibited 11 times greater Sodium concentrations, two times greater Chloride, and 50% greater Boron concentrations than samples collected from the control sites.”
Yaling Qiang, PhD, who headed the study, confirmed in a telephone interview on the 24th of October that the ill effects her team noted on the Ponderosa Pines irrigated with reclaimed wastewater was directly correlat- ed to salt accumulation from the substance’s inherently higher salinity. “The necrosis [needle burn] of the Ponderosa Pines was apparent with even those trees that received direct contact with spray application,” Dr. Qiang said.
While the Ponderosa Pine is native and widely found in Colorado, as it is here in Arizona, the most abundant growth takes place on deep, moist, and well-drained soils. Presumably, reclaimed water changes the soil composition, decreasing the drainage capacity of a native soil, as well as inhibiting the ability of the Pine to uptake the nutrients it requires. For sustenance, the Pine, just as many alpine species, requires a delicate blend of organic compounds, like Nitrogen, Potassium, Calcium, and Phosphorus, to name a few, and all in relatively exacting de- grees, for optimal growth and longevity.
If any of this balance is offset by the per- centile increases Dr. Ursula Schuch found in her reclaimed waste/potable water compari- son*, then a tree is hardly in a position to get up and walk away.
Adaptation is the key to survival for many alpine species, as SWCA, an environmental consulting firm based out of Phoenix with 20 offices nationwide, emphasizes in its re- port, concurrently sitting on Secretary Sala- zar’s desk in Washington, awaiting comment. Many of the rare species found on the San Francisco Peaks have adapted, over millen- nia, to only a few places on Earth.
The San Francisco Ragwort or Groundsel (Packera franciscana) is one of those spe- cies of the Daisy family only found on Hum- phreys and Agassiz — an area of 740 acres of Coconino National Forest. Listed as “Threat- ened” while awaiting federal determination as “Endangered,” the Groundsel is the flow- ering yellow blanket of autumn, a unique visual pleasure shared by any wanderer to the mountain.
Like many species found on the Peaks, the Groundsel is adapted specifically to an alpine ecosystem, characterized by intense solar radiation, high winds, snow and ice accumulation, and short growing seasons — resulting in an environment with low rates of plant decomposition and mineralization, making it uniquely “nutrient limited.”
Vegetation on the mountain, in other words, has learned to survive with very little organic material and requires considerably less Nitrogen, Phosphorus, Sodium, and oth- er organic elements than its cousins in lower
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