Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Climate-Based Coefficients for Scheduling Irrigations in Urban Xeriscapes

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:  5th National Decennial Irrigation Conference Proceedings, 5-8 December 2010, Phoenix Convention Center, Phoenix, Arizona USA  IRR10-10038.(doi:10.13031/2013.35893)
Authors:   Daniel Smeal, Michael K O'Neill, Kevin A Lombard, Richard N Arnold
Keywords:   landscape coefficients, xeriscape, irrigation, reference evapotranspiration, plant factors, scheduling coefficients

The decrease in water supply/demand ratios in the western U.S. is stimulating the region's municipalities to implement water conservation incentives. In response, many homeowners and businesses are replacing high water-using landscapes with drip-irrigated xeriscapes. Water-requirement information for the plant species that comprise these xeriscapes is lacking. Consequently, plants may still receive more water than necessary to sustain acceptable growth and appearance and water may not be conserved. The objectives of this project were to evaluate the growth and aesthetic quality of various drought-tolerant plants that have potential for use in urban landscapes of the western U.S. Intermountain zone under variable levels of microirrigation and then to formulate climate-based (Penman-Monteith reference ET), landscape coefficients (KL) or plant factors (PF) that may be used along with measurements of plant canopy area to develop effective irrigation scheduling recommendations for these plants. A xeriscape garden was split into four differentially irrigated sections (0, 20, 40, and 60% of reference ET) and at least one individual of more than 90 plant species were planted into each section. An average canopy area was used to adjust irrigation treatments and then actual plant canopy measurements were used to formulate PF for each species. While PF varied significantly between species, results indicate that an overall KL or PF of about 0.3 may be appropriate for water management planning on xeric landscapes.

(Download PDF)    (Export to EndNotes)