Throughout much of the Southwestern United States, poor quality water and limited water resources require innovative methods to conserve water. No research to date has indicated whether seeded bermudagrass Cynodon dactylon can be established by using subsurface drip irrigation (SDI). In 2001 (Expt. I) and 2002 (Expt. II), seeded bermudagrass was evaluated for establishment using SDI. Treatments consisted of emitters and tubing spaced at 30, 46, and 61 cm. The control treatment consisted of pop-up sprinklers. Salinity accumulation is a concern when irrigating turfgrass in areas of poor water quality and low annual rainfall. Salinity accumulation was visible at the soil surface during establishment in 2001, but turfgrass showed no visible signs of stress due to salinity. In 2002, substantial rainfall reduced salinity accumulation during establishment as salinity was not present on the soil surface. Salinity accumulation was greater in most months at the 0-15 cm depth in both years compared to the 15-30 cm depth. Full turfgrass coverage (≥90%) for the control plots in 2001 was about 8.5 weeks and the SDI treatments had complete coverage in 10 weeks. Turfgrass coverage for all treatments in 2002 was 9 weeks. Expt. II had a slightly faster establishment rate due to greater rainfall and different soil characteristics than that of Expt. I. Root count and depth of roots for both years showed roots to 61 cm depth in all treatments. A general trend of higher salinity accumulation at the midpoint between tubing was seen in Expts. I and II. However, after significant rainfall salinity levels returned to concentrations comparable to initial soil salinity concentrations in both years. This research documents the ability to successfully establish seeded bermudagrass using SDI.
Michael Maurer* and Justin Weeaks
Jeffery C. Kallestad, Theodore W. Sammis, John G. Mexal, and John White
Optimal pecan (Carya illinoiensis) production in the southwestern United States requires 1.9 to 2.5 m of irrigation per year depending on soil type. For many growers, scheduling flood irrigation is an inexact science. However, with more growers using computers in their businesses, and with soil moisture sensors and computerized data-collection devices becoming more inexpensive and accessible, there is potential to improve irrigation and water use efficiencies. In this project two low-cost soil monitoring instruments were introduced to a group of pecan producers. They were also given instruction on the use of Internet-based irrigation scheduling resources, and assistance in utilizing all of these tools to improve their irrigation scheduling and possibly yield. The objectives were to determine whether the technology would be adopted by the growers and to assess the performance of the sensors at the end of the season. Three out of the five growers in the project indicated they used either the granular matrix (GM) sensors or tensiometer to schedule irrigations, but compared to the climate-based irrigation scheduling model, all growers tended to irrigate later than the model's recommendation. Graphical analysis of time-series soil moisture content measured with the GM sensors showed a decrease in the rate of soil moisture extraction coincident with the model's recommended irrigation dates. These inflection points indicated the depletion of readily available soil moisture in the root zone. The findings support the accuracy of the climate-based model, and suggest that the model may be used to calibrate the sensors. Four of the five growers expressed interest in continued use of the tensiometer, but only one expressed a desire to use the GM sensor in the future. None of the participants expressed interest in using the climate-based irrigation scheduling model.
Daniel Hargey, Benjamin Wherley, Casey Reynolds, Richard White, and Garrett Parker
Municipal water restrictions across the southern and southwestern United States have created additional challenges for maintaining safe playing surfaces on recreational turf facilities. In recent years, many cities within these regions have begun to impose irrigation restrictions during winter months. Although winter overseeding has been regularly practiced in these areas, interest and use of colorants as an alternative to overseeding has grown due to decreasing water availability and budget concerns. Data on relative performance of colorant-treated vs. overseeded dormant turf would be of interest to turf managers, because colorants may be more cost-effective and require less water than winter overseeding. The objectives of this 2-year field study were to evaluate effects of winter treatments on performance (green cover, surface hardness, and soil moisture attributes), turfgrass injury resulting from simulated traffic, and spring transition of ‘Tifway’ bermudagrass (Cynodon dactylon L. × Cynodon transvaalensis Burtt-Davy) under a 1-day per week irrigation schedule. Treatments included 1) untreated bermudagrass, 2) fall colorant-treated bermudagrass, 3) perennial ryegrass (Lolium perenne L.) overseeded bermudagrass, and 4) turf-type annual ryegrass (Lolium multiflorum Lam.) overseeded bermudagrass. In both years, treatment differences were detected for percent green cover, soil volumetric water content (VWC), percent visual turfgrass injury, surface hardness, and percent bermudagrass transition. Percent green cover and visual turfgrass injury levels were similar between annual and perennial ryegrass in year 1, whereas loss of green cover and greater turfgrass injury were noted in annual ryegrass during the spring of year 2. Residual benefits of fall colorant applications extended into February of year 1, but dissipated by late December of year 2, likely due to higher rainfall and warmer temperatures, which prevented full bermudagrass shoot dormancy. Overseeding reduced bermudagrass spring transition by up to 50% compared with untreated and colorant-treated plots. Fall colorant treatments did not accelerate bermudagrass transition compared with untreated plots. Results of the study demonstrate that environmental differences from season to season can impact the relative benefits derived from colorant applications, as well as the performance of annual and perennial ryegrass.
Genhua Niu and Denise S. Rodriguez
Use of recycled water to irrigate urban landscapes may be inevitable, because the freshwater supply has been diminishing and the population continues to grow in the arid and semiarid southwestern United States. However, little information exists on the performance of landscape plants irrigated with nonpotable water. Two greenhouse studies were conducted during the summer and the fall to characterize the relative salt tolerance of five herbaceous perennials by irrigating the plants with a saline solution at an electrical conductivity (EC) of 0.8 dS·m–1 (tap water), 2.0 dS·m–1, or 4.0 dS·m–1. In the summer study, after 10 weeks of treatment, Achillea millefolium L., Gaillardia aristata Foug., and Salvia coccinea Juss ex J. had an aesthetically acceptable appearance for landscape performance (visual quality scores of 4 points or more), whereas Agastache cana (Hook.) Woot. & Standl. and Echinacea purpurea (L.) Moench had relatively low tolerance to salinity. Dry weight of shoots of A. millefolium, A. cana, and G. arstata was lower at elevated salinity levels. In the fall study, A. millefolium, E. purpurea, G. arstata, and S. coccinea had acceptable growth and visual quality at elevated salinity levels, whereas A. cana had lower quality and reduced growth. Dry weight of shoots was lower in G. arstata and A. millefolium at an EC of 2.0 dS·m–1 or 4.0 dS·m–1. Leaf osmotic potential of all species in the summer experiment was significantly lower at higher salinity compared with the control. In the fall experiment, leaf osmotic potential in A. millefolium, E. purpurea, and G. aristata at 4 dS·m–1 was lower compared with lower salinity treatment and the control. Leaf osmotic potential in the fall was higher than that of the same species at the same salinity level in the summer experiment, indicating that plants in the fall were less stressed than in the summer. Combined the results from both experiments, the authors concluded that A. millefolium, G. arstata, and S. coccinea had a relatively high salt tolerance (as much as 4 dS·m–1 of irrigation water under greenhouse conditions) among the tested species, whereas A. cana and E. purpurea were not tolerant to salt and should not be irrigated with low-quality water.
Garry V. McDonald, Michael A. Schnelle, and Michael A. Arnold
; Riffle and Craft, 2003 ). Studies investigating temperature trends in Texas and the southwestern United States from the years 1941 to 2000 show an overall warming trend post-1970 ( Englehart and Douglas, 2003 ). Warmer winters associated with this trend
Mexico State Univ. Coop. Ext. Serv. Publ. H335. 20 Aug. 2021. < https://aces.nmsu.edu/pubs/_h/H335.pdf > Yao, S. Heyduck, R. 2018 Ornamental jujube cultivar evaluation in the southwestern United States HortTechnology 28 557 561 https
Jay M. Lillywhite, Jennifer E. Simonsen, and Mark E. Uchanski
to foods.” Respondents were provided with information regarding the term “chile pepper” (as it is used in the southwestern United States) to clarify the difference between chile peppers and spicy peppers in general ( Fig. 2 ). Survey participants were
Shengrui Yao, Steve Guldan, and Robert Heyduck
in the southwestern United States HortScience 50 839 846 Yao, S. Guldan, S.J. Flynn, R.P. Ochoa, C. 2015b Challenges of strawberry production in high-pH soil at high elevation in the southwestern United States HortScience 50 254 258 Yao, S. Guldan, S
Gayle M. Volk and Christopher M. Richards
southwestern United States and that of the cultivated potato ( Solanum tuberosum ). He emphasized the value of collecting accurate georeferencing data during trips to that repeated visits so small populations can capture genetic shifts in population structure
Sanjit K. Deb, Parmodh Sharma, Manoj K. Shukla, Theodore W. Sammis, and Jamshid Ashigh
Salinity stress is an ever-present environmental constraint to crop productivity in arid and semiarid regions. The quality of irrigation water remains a primary factor influencing soil salinity. In the arid and semiarid southwestern United States