Jujube: a New Fruit Crop for Utah Production and Edible Low Water Landscapes 2012-14

1. Jujube (Ziziphus jujuba Mill.; also known as a Chinese date) is a drought tolerant fruit tree unknown in Utah but is widely grown in Asia for fruit quality and health benefits, both fresh and dried. Jujube tolerance of cold and dry conditions in China ostensibly suggests that it should tolerate Utah’s cold, dry and high pH conditions. Jujube’s drought tolerance is partly due to small, glossy leaves and deep root system that are also attractive for low water landscaping, particularly edible landscaping, and possibly small fruit production in Utah. However, there has been no systematic evaluation of jujube in Utah to provide a basis for recommendations to producers and home owners. In particular there is no information on minimum water needs of jujube important for production under limited water supplies and in low water edible landscaping that is becoming increasingly important. USU was awarded two sequential Specialty Crop Block Grant, 2012-2014, to study jujube water use and performance in Utah. Jujube growth and water relations were studied in 2012, showing high rates of photosynthesis and transpiration, and indeterminate growth that continued partway into fall However, during the 2013 growing season trees showed iron deficiency symptoms of leaf yellowing and no response to nitrogen fertilization high water pH. Compounding iron deficiency, extreme cold in early December 2013 killed aboveground scion wood in 90% of the plants. Undamaged roots produced many undesirable suckers. Based on these results, these two jujube cultivars tested (Lang and Candy Cane) are not well adapted to northern Utah’s high pH and risk of early, extreme cold. New Mexico State University is studying jujube in greater detail, where more information about more about jujube production in the U.S. Intermountain West is available: General overview of jujube: http://aces.nmsu.edu/pubs/_h/H-330.pdf · Detailed overview of jujube: http://hos.ufl.edu/sites/default/files/faculty/gdliu/Jujubes.pdf Jujube cultivar trial: https://newscenter.nmsu.edu/articles/view/10225/nmsu-studying-30-chinese-varieties-of-jujube-fruit-new-to-u-s Finally, this particular project at the overall level does have one research paper on jujube nutritional value that is a collaborative work with Chinese colleagues at Northwest Agriculture and Forestry University near Xi’an China: http://works.bepress.com/roger_kjelgren/146

Simple Landscape Irrigation Demand Estimation: Slide Rules

Irrigated urban landscapes must increasingly maintain economic and ecosystem value with less water in response to drought amplified and shifted by climate change. Efficient landscape water management requires estimating water amount demanded by plants that can be replaced by irrigation to meet minimum performance expectations. The extant approach to estimating landscape water demand is conceptually muddled and often regionally inappropriate. Simplified Landscape Irrigation Demand Estimation (SLIDE) Rules distills scientifically credible assumptions about urban landscape biological and physical complexity into guidelines for estimating water demand that are conceptually accessible and operationally useful. SLIDE Rules are: 1) oasis urban reference evapotranspiration (ETo) effectively represents water use of urban turf seasonally and for day-to-day irrigation scheduling, but is less accurate for estimating water use of non-turf surfaces, especially in dry climates; 2) a discrete number of Plant Factors (PF) adjust ETo to estimate water demand of general landscape plant type categories—turf, non-turf, and desert—that are adjusted for temperature and drought responses; 3) a hydrozone controlled by one irrigation valve is the smallest landscape unit manageable for water, thus overall zone irrigation is governed by the highest water demand plant within that hydrozone; 4) for hydrozone

Response of Stomatal Density and Bound Gas Exchange in Leaves of Maize to Soil Water Deficit

Stomatal behavior in response to drought has been the focus of intensive research, but less attention has been paid to stomatal density. In this study, 5-week-old maize seedlings were exposed to different soil water contents. Stomatal density and size as well as leaf gas exchange were investigated after 2-, 4- and 6-weeks of treatment, which corresponded to the jointing, trumpeting, and filling stages of maize development. Results showed that new stomata were generated continually during leaf growth. Reduced soil water content significantly stimulated stomatal generation, resulting in a significant increase in stomatal density but a decrease in stomatal size and aperture. Independent of soil water conditions, stomatal density and length in the trumpeting and filling stages were greater than in the jointing stage. Irrespective of growth stage, severe water deficit significantly reduced stomatal conductance (Gs), decreasing the leaf transpiration rate (Tr) and net photosynthetic rate (Pn). Stomatal density was significantly negatively correlated with both Pn and Tr but more strongly with Tr, so the leaf instantaneous water use efficiency (WUEi) correlated positively with stomatal density. In conclusion, drought led to a significant increase in stomatal density and a reduction in stomatal size and aperture, resulting in decreased Pn and Tr. Because the negative correlation of stomatal density to Tr was stronger than that to Pn, leaf WUEi tended to increase

Water Wise: Native Plants for Intermountain Landscapes

This comprehensive volume provides specific information about shrubs, trees, grasses, forbs, and cacti that are native to most states in the Intermountain West, and that can be used in landscaping to conserve water, reflect and preserve the region\u27s landscape character, and help protect its ecological integrity. The book is an invaluable guide for the professional landscaper, horticulturist, and others in the Intermountain nursery industry, as well as for the student, general reader, gardener, and homeowner. Water Wise is both convenient and comprehensive. The heart of the book presents hundreds of species, devoting a full page to each, with a description of appearance, habitat, landscape use, and other comments. Color photographs illustrate each plant described. A reader-friendly introduction provides important background on the ecology of the Intermountain West, along with full descriptions of native plant habitats and associations.https://digitalcommons.usu.edu/usupress_pubs/1142/thumbnail.jp

Tools for evaluating and monitoring effectiveness of urban landscape water conservation interventions and programs

Our research objective was to investigate ways to evaluate landscape water use to help cities more effectively direct water conservation programs to locations with capacity to conserve. Research was conducted in connection with a landscape irrigation evaluation delivered through a city-sponsored Water Check Program. Research efforts led to development of several assessment and monitoring tools including: Landscape Irrigation Ratio (LIR), Participant Outcome Evaluation Tool, and Program Evaluation Tool. We utilized these tools to identify locations with capacity to conserve water applied to landscapes, compare water use before and after the water check, and evaluate Water Check Program effectiveness. We found the LIR approach successfully distinguished residential locations efficiently or acceptably using water applied to landscapes from ones with use considered inefficient or excessive. In analyzing change in participants’ water use and eliminating explanations other than the water check, we found factors influencing landscape water use tend to be highly contextualized and the intervention itself needed to be analyzed. The majority of participants who adopted the water check recommendations successfully reduced their landscape water use, but results indicate water check programs can be designed for greater effectiveness by accommodating participants’ differing knowledge and skill levels. We argue that the tools we developed provide the water conservation field with a needed set of common assessment methods. We conclude that landscape water checks have the potential to provide people with the information and problem-solving skills necessary to maintain residential landscapes using appropriate amounts of water if they are well designed, delivered, and monitored

Plant Species vulnerability to climate change in peninsular Thailand.

The objective of this research study was to evaluate the consequences of climate change on shifts in distributions of plant species and the vulnerability of the species in Peninsular Thailand. A sub-scene of the predicted climate in the year 2100, under the B2a scenario of the Hadley Centre Coupled Model, version 3 (HadCM3), was extracted and calibrated with topographic variables. A machine learning algorithm based on the maximum entropy theory (Maxent) was employed to generate ecological niche models of 66 forest plant species from 22 families. The results of the study showed that altitude was a significant factor for calibrating all 19 bioclimatic variables. According to the global climate data, the temperature in Peninsular Thailand will increase from 26.6 C in 2008 to 28.7 C in 2100, while the annual precipitation will decrease from 2253 mm to 2075 mm during the same period. Currently, nine species have suitable distribution ranges in more than 15% of the region, 20 species have suitable ecological niches in less than 10% while the ecological niches of many Dipterocarpus species cover less than 1% of the region. The number of trees gaining or losing climatically suitable areas is quite similar. However, 10 species have a turnover rate greater than 30% of the current distribution range and the status of several species will in 2100 be listed as threatened. Species hotspots are mainly located in large, intact protected forest complexes. However, several landscape indices indicated that the integrity of species hotspots in 2100 will deteriorate significantly due to the predicted climate change

Value Landscape Engineering: identifying costs, water use, labor, and impacts to support landscape choice.

We present a spreadsheet model that identifies the costs, water, labor, fertilizer, pesticides, fuel, energy, carbon emissions, and particulates required of and generated by a user-specified residential or commercial landscape over its economic life. This life includes site preparation, materials purchase, installation, annual maintenance and replacing landscape features that wear out or die. Users provide a variety of site-descriptive information and the model queries an extensive database of landscape data to calculate costs, required inputs, and impacts. We verified model results against observations of water, labor, fertilizer, and fuel use over eight years at three landscapes in the Salt Lake City, Utah metropolitan region. We use the model to show tradeoffs in costs and required inputs for a predominately cool-season turfgrass landscape typical for Salt Lake City and other high desert, intermountain western United States cities and potential modifications to that typical landscape. Results highlight strategies water conservation programs can use to encourage property owners to install and adopt water-conserving landscape features and practices. Residential and commercial landscapers, landscape architects, contractors, and property owners can also model current and proposed landscapes and use results to identify a low-cost, low-input landscape that achieves their client’s or their own goals and values

A Tree-Ring Based Reconstruction of Logan River Streamflow, Northern Utah

We created six new tree‐ring chronologies in northern Utah, which were used with preexisting chronologies from Utah and western Wyoming to reconstruct mean annual flow for the Logan River, the largest tributary of the regionally important Bear River. Two reconstruction models were developed, a “Local” model that incorporated two Rocky Mountain juniper chronologies located within the basin, and a “Regional” model that also included limber pine and pinyon pine chronologies from a larger area. The Local model explained 48.2% of the variability in the instrumental record and the juniper chronologies better captured streamflow variability than Douglas‐fir collected within the Logan basin. Incorporating chronologies from the northern and southern margins of the transition zone of the western precipitation dipole increased the skill of the Regional model (r 2 = 0.581). We suggest the increased Regional model skill indicates that both nodes of the western precipitation dipole influence northern Utah climate. The importance of Rocky Mountain juniper in both reconstructions of streamflow for this region suggests that future work should target these trees where more traditionally desirable species are not present. The reconstructions provide the first extended record of streamflow in northern Utah. Preinstrumental streamflows (1605–1921) exhibited considerable variability when compared to the instrumental period (1922–2005). Our findings confirm that the inherent uncertainty in contemporary water management and planning in the region is due to hydroclimatic variability that has persisted for at least the last four centuries

Interactive Effects of Water and Fertilizer on Yield, Soil Water and Nitrate Dynamics of Young Apple Tree in Semiarid Region of Northwest China

Exploring the interactive effect of water and fertilizer on yield, soil water and nitrate dynamics of young apple tree is of great importance to improve the management of irrigation and fertilization in the apple-growing region of semiarid northwest China. A two-year pot experiment was conducted in a mobile rainproof shelter of the water-saving irrigation experimental station in Northwest A&F University, and the investigation evaluated the response of soil water and fertilizer migration, crop water productivity (CWP), irrigation water use efficiency (IWUE), partial factor productivity (PFP) of young apple tree to different water and fertilizer regimes (four levels of soil water: 75%–85%, 65%–75%, 55%–65% and 45%–55% of field capacity, designated W1, W2, W3 and W4, respectively; three levels of N-P2O5-K2O fertilizer, 30-30-10, 20-20-10 and 10-10-10 g plant−1, designated F1, F2 and F3, respectively). Results showed that F1W1, F2W1 and F3W1 had the highest average soil water content at 0~90 cm compared with the other treatments. When fertilizer level was fixed, the average soil water content was gradually increased with increasing irrigation amount. For W1, W2, W3 and W4, high levels of water content were mainly distributed at 50~80 cm, 40~70 cm, 30~50 cm and 10~30 cm, respectively. There was no significant difference in soil water content at all fertilizer treatments. However, F1 and F2 significantly increased soil nitrate-N content by 146.3%~246.4% and 75.3%~151.5% compared with F3. The highest yield appeared at F1W1 treatment, but there was little difference between F1W1 and F2W2 treatment. F2W2treatment decreased yield by 7.5%, but increased IWUE by 11.2% compared with F1W1 treatment. Meanwhile, the highest CWP appeared at F2W2 treatment in the two years. Thus, F2W2 treatment (soil moisture was controlled in 65–75% of field capacity, N-P2O5-K2O were controlled at 20-20-10 g·tree−1) reached the best water and fertilizer coupling mode and it was the optimum combinations of water and fertilizer saving

Estimating landscape irrigated areas and potential water conservation at the rural-urban interface using remote sensing and GIS

Research goals were to analyze patterns of urban landscape water use, assess landscape water conservation potential, and identify locations with capacity to conserve. Methodological contributions involved acquiring airborne multispectral digital images over two urban cities which were processed, classified, and imported into a GIS environment where landscaped area were extracted and combined with property and water billing data and local evapotranspiration rates to calculate landscape irrigation applications exceeding estimated water needs. Additional analyses were conducted to compare classified aerial images to ground-measured landscaped areas, landscaped areas to total parcel size, water use on residential and commercial properties, and turf areas under tress when they were leafed out and bare. Results verified the accuracy and value of this approach for municipal water management, showed more commercial properties applied water in excess of estimated needs compared to residential ones, and that small percentages of users accounted for most of the excess irrigatio