• Aerobic and Anaerobic Grape Pomace Composting: The Pros and Cons

      Mpanga, Issac K. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2022-01)
      In Arizona, wine production increased from 65,413 gallons (2007) to 297,145 gallons 2017) (Murphree, 2018), with an estimated 354% increase in grape pomace production within the same period. The grape pomace is a by-product of the wineries, which is obtained after crashing the grape fruits, fermenting and pressing the juice.
    • Arizona Cooperative Alfalfa Forage Yield Trials (1993-2020)

      Ottman, Michael J.; White, Jeffrey W.; Smith, Steven E. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2022-03)
      The Arizona Cooperative Alfalfa Forage Yield Trial Program, administered by the Arizona Agricultural Experiment Station and Arizona Cooperative Extension, conducted alfalfa forage yield trials at the University of Arizona's Agriculture Centers in Maricopa and Tucson. The Maricopa location is at 1188 ft elevation and has a sandy loam soil. The Tucson location is at 2352 ft elevation and has a very fine sandy loam soil. Very non-dormant cultivars are well-adapted to this environment, which is typical of agricultural areas of the low elevation deserts of Arizona where 8 to 10 harvests of alfalfa are common each year and stands typically remain productive for 2 to 4 years. All fields were laser-leveled and alfalfa was irrigated using the border-strip methods.
    • Arizona’s Seasonal Role in National Supply of Vegetable & Melon Specialty Crops

      Duval, Dari (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-09)
      Arizona’s agricultural industries are diverse, producing a wide variety of field crops, orchard crops, fruits and vegetables, livestock, and livestock products. Western Arizona, including the Yuma area, and Central Arizona to a lesser extent, play niche roles in the production of specialty vegetable and melon crops. Because of geography and climate, Western and Central Arizona serve as the leading source and at times even exclusive source of certain commodities at the national level. This analysis provides an overview of Arizona’s seasonal role in supplying certain commodities nationally.
    • Citrus Fertilization Chart for Arizona

      Wright, Glenn C. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2015-06)
      To promote optimal growth and production of your citrus tree, use the chart to determine the correct amount of fertilizer to apply.
    • Consumptive Water Use of Pecans in Southern Arizona

      Brown, Paul W.; Walworth, James L. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-07)
      The production of pecans [Carya Illinoinensis (Wangeh.) K. Koch] in Arizona has increased substantially in recent years (Parsons, 2017; Murphree, 2020). A recent economic impact study indicates more than 30,000 acres of pecans are now established in Arizona, nearly double the acreage reported in 2013 (Duval et al., 2019). The majority of Arizona pecan orchards are located in Southern Arizona
    • Cultivation of Mixed Summer Cover Crops (Buckwheat, Cowpea, and Teff Grass) In High Tunnels

      Mpanga, Isaac K. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2022-01)
      Cover crops are grown to cover the soil surface. They are planted between main crops or as an alternative to cash crops and provide many benefits ranging from soil erosion control, improved soil fertility, soil health (Reeves, 1994; Wang and Nolte, 2010), and increased biodiversity (Drinkwater et al., 1995). The use of cover crops among small-scale farmers can be challenging due to the limited space, resource, equipment needs, and the nature of operations. In high tunnel production systems, the use of tractors is limited, and growing cover crops requires careful crop selection, termination timing, and management for maximum benefits. High tunnels are plastic-covered structures that provide a partial controlled environment passively heated in winter and ventilated in summer. For environmental protection and control, high tunnels are between the open-field (natural environment) and completely controlled environments in a greenhouse. Compared to a standard greenhouse, a high tunnel is a low-cost structure, often with in-ground production, and low operating costs. This study determined biomass production and shoot mineral composition of mixed summer cover crops (buckwheat, cowpeas, and teff grass) to determine the optimum termination time while minimizing management inputs and obtaining maximum soil health benefits from the cover crops. Recommendations outline how small-scale farmers can grow cover crops in high tunnels.
    • Effects of the Application of Balanced Phosphorus and Potassium Fertilizers on Alfalfa Yield and Yield Components

      Mostafa, Ayman; Harrington, Kyle; Burayu, Worku (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2022-09)
      Alfalfa (Medicago sativa L.) stands normally provide the highest yield in their first two or three production years, and then start to decline thereafter, where sometimes re-establishing the stand becomes necessary. As re-establishing a stand is costly, it may be more profitable to improve management practices that will keep stands high yielding for more years. Towards that end, several research projects have been conducted in the low desert of Arizona. An on-farm study at Buckeye, Arizona indicated that application of phosphorus (P) fertilizer at 104 lb P2O5 per acre significantly increased (8.7%) hay yield (Ottman et al 2015). Other research has revealed that various phosphorus fertilizer sources had equal effect on alfalfa forage at equivalent rates of application (Burayu et al 2016) & (Brouder et al. 2005).
    • Embracing Variable Rate Technology in Arizona Crops:Geographic Visualization of Field Zone Management

      Andrade-Sanchez, Pedro; Heun, John T. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2022-03)
      The concept of “Zone Management” in US agriculture emerged in the early 2000’s; it derived from the paradigm shift towards site-specific management of production inputs. The technological driver that fueled this change was the introduction of satellite-based global positioning systems (GPS) of sub-meter precision. Since then, Precision Agriculture (PA) has evolved as an academic discipline to study the relationships between digital technology, its user interface, and the characteristics of the farming system where it is intended to be implemented. Moreover, PA is an intensively practical and applied discipline, embraced by a large segment of practitioners and service providers in the US agricultural community and abroad.
    • Enterprise Budgets: Alfalfa Hay Production, Flood Irrigated, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs and returns to grow alfalfa hay using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Cotton, Flood Irrigated, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs and returns to grow cotton using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Durum Wheat, Following Cotton, Flood Irrigated, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs and returns to grow durum wheat after a cotton crop using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Fallow, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs to maintain land in fallow in southern Arizona. It should be used as a guide to estimate actual costs and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Silage Corn, Flood Irrigated, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs and returns to grow silage corn using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Guayule, Flood Irrigated, Southern Arizona

      Teegerstrom, Trent; Seavert, Clark; Gutierrez, Paul; Summers, Hailey; Sproul, Evan; Evancho, Blase; Ollerton, Paco (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This series of enterprise budgets estimate the typical economic costs and returns to establish, grow, and harvest guayule over a six-year period, using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing these budgets are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Enterprise Budgets: Spring Barley, Following Cotton, Flood Irrigated, Southern Arizona

      Evancho, Blase; Ollerton, Paco; Teegerstorm, Trent; Seavert, Clark (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      This enterprise budget estimates the typical economic costs and returns to grow spring barley after a cotton crop using flood irrigation in southern Arizona. It should be used as a guide to estimate actual costs and returns and is not representative of any farm. The assumptions used in constructing this budget are discussed below. Assistance provided by area producers and agribusinesses is much appreciated.
    • Evaluating an in-situ, Low-Cost Soil CO2 Sensor as a Soil Health Assessment Tool in Agricultural Soils

      Sanyal, Debankur; Heun, John; Stackpole, Charles; Andrade-Sanchez, Pedro (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-12)
      Measurements of carbon dioxide (CO2) emissions from agricultural soils are essential to understand the journey of an agricultural operation toward sustainability. Existing commercial technologies to measure CO2 emissions are expensive and require advanced technical knowledge. A new, low-cost, in-situ CO2-measuring device was designed and standardized by the authors to upscale CO2 emission measurements in commercial agricultural operations, spatially and temporally. We present an initial report from our preliminary studies as we measured CO2 emissions in different agroecosystems and compared different management strategies. Diurnal soil respiration or CO2 emission was also measured under different weather conditions. We coined the term, Potential Soil Respiration or PSR, to indicate the CO2 emission from soils with actively growing crops. Our data revealed that cover cropping influenced carbon storage in the soil while fallowing continued to lose soil carbon in a cotton production system, which was correlated with plant vigor. We are also working toward integrating this sensory system with other existing or new sensory systems to be deployed in commercial agricultural operations for effective natural resource management and environmental stewardship.
    • Evaluating Forage Cover Crop Mixes for the Desert Southwest

      Sanyal, Debankur; Stackpole, Charles; Megdal, Sharon B. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-08)
      Cover crops are essential tools to improve soil health and productivity1. Traditionally, cover crops are used as ‘green manures’ where the cover crops are not harvested but incorporated into the ground to boost soil health and fertility. Therefore, it has become a common perception that cover crops are meant to be incorporated into the soil. In the desert Southwest, water scarcity forces the producers to utilize water more strategically, and green manure cover crops may not be an economically sustainable option for farmers in the desert.
    • Growing and Selling Seed in Arizona: An Overview of Policy and Regulations

      Thompson, Anita B. (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-02)
      Insight into the seed industry in Arizona can be confusing for new seed farmers and companies entering the business of seed production. Seeds can be grown in Arizona for fruit and vegetable production, forage for livestock, food or non-food products, and land restoration purposes. The Seed Trade Association of Arizona (STAA) stated “Arizona produces millions of dollars’ worth of seed that is distributed throughout the world.” Unfortunately, there is no readily available data as to the impact the Arizona seed industry has on state and local economies and how much seed is grown in the state specifically for consumer use.
    • Guayule Cultivation and Irrigation Methods for the Southwestern United States

      Elshikha, Diaa Eldin (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-03)
      As water becomes scarce in Arizona there is a desire by growers to grow crops that use less water. With hundreds of acres already planted across the state and the plan to scale to 10,000 acres over the course of three years, guayule has become a more water wise crop than traditional desert row crops like silage corn, alfalfa, and cotton. In this guide, cultivation and irrigation methods will be discussed to increase area under guayule across the state.
    • Irrigated Pastures in Arizona

      Ottman, Michael J.; Wright, Ashley Diane (College of Agriculture, Life & Environmental Sciences, University of Arizona (Tucson, AZ), 2023-01)
      A pasture is a parcel of land sown to low growing plants suitable for grazing by animals (Fig. 1). The plants could be grasses and/or legumes. Pastures may be intended for only a single cropping season or, more typically, are more permanent in nature and based on perennial plant species although annual plant species may be over-seeded into a permanent pasture. The animals that graze pastures may include cattle, horses, sheep, and goats. Irrigated pastures are used as a convenient way to feed livestock without the labor, expense, and equipment required to harvest forage particularly for small farms. Most pastures in Arizona are not productive without irrigation and tend to be intentionally seeded with particular plant species, which will be the focus of this publication.