• Wheat and barley varieties for Arizona, 2017

      Ottman, Michael J (College of Agriculture, University of Arizona (Tucson, AZ), 2017-10)
      Grain yield, test weight, and other characteristics of barley, durum, and wheat varieties are provided in this publication. Revised 2017, Previous version10/2016. Previous version 10/2015.
    • Compost Tea 101: What Every Organic Gardener Should Know

      Joe, Valerisa; Rock, Channah; McLain, Jean; Univ Arizona, Coll Agr & Life Sci (College of Agriculture, University of Arizona (Tucson, AZ), 2017-08)
      Growers of organic produce in the Southwestern United States face many challenges, including variation in water and temperature, and exposure to insects and disease. As a result, smallholder organic farmers are increasingly relying on soil additives such as compost tea that improve product quality, use less water, deter pests, and reduce reliance on chemical additives (Diver, 2002). But what exactly is compost tea? Do the benefits of using compost tea outweigh any concerns? For example, can it contain pathogens, and if so, do applicators have to worry about coming into contact with pathogens? This publication provides facts about making compost tea, and reviews both the benefits and potential disadvantages to help smallholder farmers to make educated decisions regarding the use of compost tea.
    • Watering Trees and Shrubs: Simple Techniques for Efficient Landscape Watering

      Call, Robert E.; Daily, Cado; Univ Arizona, Coll Agr & Life Sci (College of Agriculture, University of Arizona (Tucson, AZ), 2017-08)
      Techniques and tips on watering trees and shrubs efficiently. Topics include weather, plant type, soil type and signs of under and over watering. Originally published 2006
    • Questions to ask when planning to start a wholesale plant nursery

      Schuch, Ursula K. (College of Agriculture, University of Arizona (Tucson, AZ), 2017-07)
      The plant nursery business is complex and requires knowledge about the technical aspects of growing plants and managing a business. This publication is an introduction for those interested in starting their own wholesale nursery business. Different types of production systems - container and field production- are discussed as well as the types of plants typically grown in Southwest nurseries. Starting a business involves many decisions that will culminate in the development of a business plan. Resources for new producers include national, regional, and local trade organizations. A worksheet with questions is included to help future operators consider whether they want to start a new wholesale production nursery. Publication AZ1393 Revised 07/2017. Originally published 2006
    • A Study of Irrigation Requirements of Southwestern Landscape Trees

      Schuch, Ursula; Martin, Edward C. (College of Agriculture, University of Arizona (Tucson, AZ), 2017-07)
      Trees are an important component of our landscapes, providing many benefits from shade to cleaning the air. Large, mature trees provide the greatest benefits in urban landscapes compared to smaller, younger trees and it is therefore important to ensure that trees in our urban forests receive the amount of water they need to develop into healthy, mature specimens.
    • Ancient Rediscovering Food: Grain Amaranth

      Moya Cortazar, Sheila; Ottman, Michael; McDaniels, Amanda; Aragon Cereceres, Andrea; Hongu, Nobuko (College of Agriculture, University of Arizona (Tucson, AZ), 2017-04)
      Grain amaranth was a dietary staple for Central American Indians before Columbus arrived in the New World.1 Today, in Mexico, amaranth is popped like popcorn and mixed with sugar or honey to make a popular sweet treat, called “Alegría” which is the Spanish word for joy (Figure 1). Amaranth is a nutritious grain, similar to chia seeds2 and quinoa, providing high amount of plant protein, fiber, iron, and calcium. This article can help you learn more about amaranth, and show you how to incorporate them into your balanced diet.
    • Row Spacing Effect on Forage Sorghum Yield and Quality at Maricopa, AZ, 2015

      Ottman, Michael J; Diaz, Duarte E; Sheedy, Michael D; Ward, Richard W; Univ Arizona, Coll Agr & Life Sci (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      Forage sorghum yields have been should to increase with narrow row spacing of 20 inches or less. The purpose of this research is to determine the effect of narrow row spacing on forage sorghum yield and quality in Arizona. Two row spacing (20 and 40 inch) and two forage sorghum hybrids (Great Scott and Silo 700D BMR) were evaluated in a study conducted at the University of Arizona Maricopa Agricultural Center in 2015. Row spacing had no effect on forage yield, moisture, plant height, or maturity even though light interception was greater for the closer row spacing. The only feed quality parameter affected by row spacing was lactic acid which increased with row spacing. Hybrid by row spacing interactions was detected for a few feed quality parameters. Decreasing forage sorghum row spacing from 40 to 20 inches does not appear to have an advantage based on the results of this study.
    • Cómo Determinar la Cantidad de Agua de Riego Aplicada a una Parcela

      Martin, Edward C.; Munoz, Carolina (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      La estimación acertada de la cantidad de agua aplicada a una parcela es crítica para cualquier esquema de manejo del riego. Muy a menudo, los agricultores aplican agua para hacer que la parcela y los surcos “se vean bien” (oscurecer las camas de los surcos) o continuan regando hasta que el agua llega al final de cada surco. Sin embargo, con frecuencia no tienen una idea precisa de cuanta agua han aplicado. Cuando los agricultores no toman en cuenta la eficiencia de sus sistemas de riego, pueden estar aplicando demasiada o muy poca agua. Muy poca agua ocasiona un estrés hídrico innecesario y puede resultar en reducciones de rendimiento. Demasiada agua puede causar estancamiento del agua, pérdida de nutrientes por excesiva infiltración y puede resultar en una pérdida de la cosecha. Reviewed 01/2017; Originally Published 04/2011.
    • Irrigation Interval Effect on Yield and Quality of Forage Sorghum at Maricopa, AZ, 2015

      Ottman, Michael J; Diaz, Duarte E; Sheedy, Michael D; Ward, Richard W (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      Sorghum has the advantage compared to corn in that it uses less water and fertilizer, but feeding quality of sorghum is usually less than corn. The purpose of this research is to compare the yield and quality of sorghum grown with differing frequency of irrigation water application. Forage sorghum was grown at the University of Arizona Maricopa Agricultural Center with irrigation intervals of 1, 2, and 3-weeks corresponding to 76, 44, and 37 inches of applied water. Forage yield at 72% moisture was 20.6, 18.8, and 16.5 tons/acre for the 1-, 2-, and 3-week irrigation intervals, respectively. Forage quality in terms of milk per ton of forage was not affected by irrigation interval, but some differences were measured in certain components of feed quality. Forage yield profit was maximized at the 2-week irrigation interval due since the increased water cost of the 1-week interval was not compensated by the yield increase at this irrigation frequency.
    • Forage Sorghum Hybrid Yield and Quality at Maricopa, AZ, 2015

      Ottman, Michael J; Diaz, Duarte E; Sheedy, Michael D; Ward, Richard W (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      Forage sorghum is commonly grown in Arizona for silage for dairy cattle and is valued for its lower nitrogen fertilizer and water requirements compared to corn. Five forage sorghum hybrids were evaluated in a study conducted at the Maricopa Agricultural Center in 2015. The hybrids tested did not differ in yield or overall feeding quality (TDN, total digestible nutrients) although some differences in heading, plant height, moisture content, and some specific quality parameters were detected.
    • Nitrogen Fertilizer Rate Effect on Forage Sorghum Yield, Quality, and Tissue Nitrogen Concentrations at Maricopa, AZ, 2015

      Ottman, Michael J; Diaz, Duarte E; Sheedy, Michael D; Ward, Richard W (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      A nitrogen fertilizer study was conducted in order to determine the effect of N rates on forage sorghum yield and quality and to develop tissue testing guidelines for fertilizer application to forage sorghum. The study was conducted at the University of Arizona Maricopa Agricultural center on sandy clay loam soil irrigated using the flood method. Forage sorghum was fertilized with six N rates varying from 0 to 250 lb N/acre in 50 lb N/acre increments. The whole plant, lower stem, and most recently expanded leaf were sampled five times during the growing season and analyzed for N content in order to establish tissue N guidelines for fertilizer application. The plant part that was most sensitive to N fertilizer application and plant N status was lower stem. Leaf and plant N levels were not affected by fertilizer application. The stem nitrate and stem N tests were able to identify N deficient plants very early in the season, long before plant growth was affected by the N deficiency, unlike leaf and plant N. Forage yield at final harvest fitted to a quadratic function was maximized at the 250 lb N/acre N rate. However, the yield increase with any amount of fertilizer did not pay for the cost of the fertilizer and the most economical N rate for yield was no N fertilizer applied at all. In terms of milk per acre, the maximum was achieved at 150 lb N/acre, and the economic optimum in terms of milk was slightly less than this amount of fertilizer.
    • 2016 Cotton Variety Testing Results – Report

      Norton, Randy; Ayman, Mostafa (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      Variety selection is one of the most important decisions a grower will make contributing to the success of a cotton crop. It is critical, that a grower have as much information as possible in order to make an informed decision regarding variety selection. In an effort to help supply reliable variety performance information, the University of Arizona conducts a statewide Upland cotton variety testing program. This program consists of a few different types of trials. The first is a small plot evaluation of commercially available varieties along with experimental varieties, and is conducted in 3 locations across Arizona including; Yuma, Maricopa, and Safford. This testing program is called the University of Arizona Upland Cotton Advanced Strains Testing Program.
    • Cómo Medir el Flujo de Agua en los Canales de Riego a Cielo Abierto y en las Tuberías de Compuertas

      Martin, Edward C.; Munoz, Carolina (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      La medición del agua en los sistemas de riego por gravedad es crítica para obtener el manejo óptimo y eficiente del agua. Sin conocer la cantidad de agua que se está aplicando a la parcela es difícil decidir adecuadamente cuando parar o cuándo hacer el siguiente riego. Para que un regador haga un manejo adecuado del agua debe saber el caudal o gasto, el tiempo total del riego y el tamaño de la superficie regada. A partir de estos datos se puede determinar la cantidad de agua que se aplicó a la parcela, lo cual entonces ayudará a determinar si el riego fue adecuado o no y cuándo se debería hacer el siguiente riego. Las decisiones en cuanto al manejo del riego deben hacerse en base a la cantidad de agua aplicada y a su relación con la demanda de consumo de las plantas y la capacidad del suelo para retener el agua. Revised 01/2017; Originally Published 12/2010.
    • Effect of Amount of Irrigation Water Applied on Forage Sorghum Yield and Quality at Maricopa, AZ, 2015

      Ottman, Michael J; Diaz, Duarte E; Sheedy, Michael D; Ward, Richard W (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      Irrigation water is a major input into production of a forage crop. The purpose of this research is to compare the yield and quality of forage sorghum grown with differing amounts of irrigation water. A linear move sprinkler system was used to apply 11 water application amounts from 23.79 to 35.52 inches over the season. Forage yield peaked at a water application amount of around 32.60 inches according to a quadratic function of yield vs water applied. Increasing irrigation amount decreased forage quality by increasing fiber components. Profit was maximized at 30.20 to 32.60 inches of applied water, which is slightly less than that for maximum yield.
    • Métodos para Medir la Humedad del Suelo para la Programación del Riego ¿Cuándo?

      Martin, Edward C.; Munoz, Carolina (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      El manejo apropiado del riego requiere la evaluación de parte del agricultor de sus necesidades de riego en base a medidas de varios parámetros físicos del suelo. Algunos productores utilizan equipo sofisticado mientras que otros se basan en métodos empíricos o en el sentido común. Cualquiera que sea el método usado, cada uno tiene sus propios méritos y limitaciones. El agricultor generalmente se hace dos preguntas al desarrollar una estrategia para el manejo del riego: “¿Cuándo regar?” y “¿Cuánta agua aplicar?”. Este boletín responde a la pregunta CUÁNDO. Reviewed 2/2017; Originally Published 09/2010.
    • Cómo Convertir de Galones a Pulgadas, y Determinar el Tiempo de Operación Para los Sistemas de Riego por Goteo en Cultivos en Surcos

      Martin, Edward C.; Barreto, Armando (College of Agriculture, University of Arizona (Tucson, AZ), 2017-02)
      La conversión de sistemas de riego por gravedad a sistemas por goteo requiere más que la inversión de capital. Los agricultores y regadores deben adaptar sus estrategias de manejo para dar acomodo al nuevo sistema de riego. En particular, los sistemas por goteo no están diseñados para aplicar las grandes candidades de agua de riego que la mayoría de los sistemas por gravedad sí son capaces de aplicar. Dependiendo del diseño y distribución del sistema por goteo, este sistema puede tomar varias horas para aplicar una pulgada de agua a la parcela, mientras que la mayoría de los sistemas por gravedad pueden aplicar de 4 a 8 pulgadas en 12 horas. Debido a esta diferencia, los agricultores que utilizan sistemas por goteo necesitan monitorear muy de cerca la condición de humedad del suelo de sus campos regados por goteo y regar apropiadamente. Reviewed 01/2017; Originally Published 05/2011.
    • Potential Yield Increase by Grafting for Watermelon Production in Arizona

      Kroggel, Mark; Kubota, Chieri (College of Agriculture, University of Arizona (Tucson, AZ), 2017-01)
      Grafting cucurbits onto rootstocks resistant to diseases and abiotic stresses can be a methodto overcome limited availability of effective pre-plant fumigants or land to rotate and to allowearlier planting. Commonly used rootstocks for cucurbits have resistance to Fusarium (race1&2) as well as cold tolerance, among other favorable traits like increased vigor of the scion. Grafting of cucurbits was developed in Asia primarily to allow production without rotation, because arable land is so limited. In the US, crop rotation schedules for seedless watermelon can be 3 years or longer reducing the amount of watermelon a grower can produce in a season. We have been growing grafted and non-grafted seedless watermelon on the same field/plot for 4 years, with no fumigation or off-season rotation of other crops. During the last 2 years, we planted early (March 1) to determine if grafting could overcome low night temperatures in addition to disease pressures. Treatments included grafted and non-grafted plants, covering with frost protection and non-covered. The results of the last 2 years indicate that grafted plants yielded nearly twice as much as non-grafted plants, suggesting that grafting can be a promising technology for Arizona watermelon producers.
    • Using Repeat Color Photography as a Tool to Monitor Rangelands

      Howery, Larry D.; Sundt, Peter C. (College of Agriculture, University of Arizona (Tucson, AZ), 2016-12)
      This article provides an introduction to repeat color photography and explains how it can be used as an important part of a comprehensive rangeland monitoring program. Reviewed 12/2014. Originally published 05/1998.
    • A Summary of Livestock Grazing Systems Used on Rangelands in the Western United States and Canada

      Howery, Larry D.; Sprinkle, James E.; Bowns, James E. (College of Agriculture, University of Arizona (Tucson, AZ), 2016-12)
      The objectives of this article are to provide an overview of the major grazing systems that have been used on rangelands in the western U. S. and Canada, to summarize the conditions under which they may be applicable, and to highlight examples from the southwestern U. S. when relevant. Revised 12/2014. Originally published 09/2000.
    • Late Season N Application Method Effect on Grain Protein, 2016

      Ottman, Michael J; Sheedy, Michael D; Ward, Richard W (College of Agriculture, University of Arizona (Tucson, AZ), 2016-11)
      Nitrogen fertilizer is normally applied later in the season around flowering time to boost grain protein content. The purpose of this study is to determine if the grain protein boost provided by late N application is affected by method of application. A trial testing late season N application methods was conducted at the Maricopa Ag Center in the 2016 growing season. The crop was grown 211 lb N/acre in split applications until flowering when 35 lb N/acre was applied as UAN32 in the irrigation water (fertigation), as low biuret urea in a foliar application, or as urea granules compared to no N application at all at flowering. In this study, we were not able to detect a difference in grain protein or any other variable measured due to the late N application method. We did measure a 0.4% increase in grain protein regardless of late season N application method compared to the control with no late N applied.