Edward C Martin
- Associate Vice President and Director, Cooperative Extension
- Specialist, Agricultural-Biosystems Engineering
- Professor, Agricultural-Biosystems Engineering
- Member of the Graduate Faculty
Dr. Ed Martin is the County Director for Maricopa County Cooperative Extension, College of Agriculture and Life Sciences, University of Arizona. He is the chief administrator for the office of almost 80 employees who bring science-based research to help solve real life problems to improve the lives, communities and the economy in Maricopa County and beyond. Dr. Martin is also an Extension Irrigation Specialist and Professor in the Agricultural & Biosystems Engineering Department of the UA and serves as the Editor In-Chief of UA Cooperative Extension publications. Originally from Michigan, he received his Ph.D. from Michigan State University in Agricultural Technology and Systems Management. He has been with the University of Arizona since 1992 where he began his tenure as an Extension Specialist in Irrigation, located at the Maricopa Agricultural Center, a 2000 acre research farm located 30 mile southwest of Phoenix. His research centered on the efficient and effective management of agricultural irrigation water. Concentrating on on-farm management, Dr. Martin researched crop water use and helped develop the AZSCHED (Arizona Irrigation Scheduling) program that helped growers better apply and manage their irrigation water applications. He also has worked on water quality issues, looking at the effects of manure and compost application to the movement and drainage of nitrogen and other plant nutrients. He has done extensive work on the Navajo Nation, working on the promotion of gravity fed drip irrigation systems. His demonstration and research projects have been installed at the Hubbell Trading Post, in Canyon DeChelly National Monument, and at community and family farms throughout the Navajo Nation. Working closely with Extension personnel from Dinè College in Tsaile, a 1994 Land Grant Institution, he continues his work today, looking at alternative irrigation systems that can be utilized in communities such as the Wheatfields Chapter. In 2007, he was asked to serve as the Associate Director for Extension, Program Leader for the Agriculture and Natural Resource programs at the University of Arizona. During his tenure there, he helped to transform Extension’s web and social media presence, working to develop a new web management system that allows users to enter their own information, decentralizing the control of web content and exposing a new generation of faculty and staff to the possibilities of social media while capitalizing on younger staff who already possessed the required skills. He also worked to develop brochures and other media that complimented each other, forming a singular message about the impacts of Extension within the state. In 2012, he was asked to serve as interim director for Maricopa County Cooperative Extension. Maricopa County is the 4th largest county in the US, with over 4 million people. Programs range from the more traditional agriculture and 4-H programs, to the more urbanized community garden and SNAP-Ed programs. In 2013, Dr. Martin was named County Director. At Maricopa County, he has initiated projects on developing the main building’s landscape into a living classroom and renovating office technology. He helped oversee a $750,000 renovation of the main office and works to keep the office, staff, faculty, and programs relevant to the needs of the people of Maricopa County and beyond.
- Ph.D. Agricultural Systems Technology
- Michigan State University, East Lansing, Michigan
- M.S. Agriculture and Extension Education
- Michigan State University, East Lansing, Michigan
- B.S. Agricultural Engineering
- Michigan State University, East Lansing, Michigan
- University of Arizona, Tucson, Arizona (2021 - Ongoing)
- University of Arizona, Phoenix, Arizona (2013 - Ongoing)
- University of Arizona, Tucson, Arizona (2007 - 2013)
- University of Arizona, Tucson, Arizona (2005 - Ongoing)
- University of Arizona, Tucson, Arizona (1998 - 2005)
- University of Arizona, Tucson, Arizona (1992 - 1998)
Irrigation Scheduling, On-Farm Water Management, Crop Water Use, Irrigation Systems Management
No activities entered.
- Martin, E. C. (2017). Arizona Master Gardener Manual. University of Arizona: University of Arizona Cooperative Extension.
- Subramani, J., Martin, E. C., Subramani, J., Schuch, U. K., Martin, E. C., & Mahato, T. R. (2016). Response of desert-adapted landscape trees to deficit irrigation. Acta Horticulturae, 193-200. doi:10.17660/actahortic.2016.1112.27
- Basso, B., Simone, L. d., Cammarano, D., Martin, E. C., Margiotta, S., Grace, P. R., Yeh, M. L., & Chou, T. Y. (2012). Evaluating responses to land degradation mitigation measures in southern Italy. International Journal of Environmental Research, 6(2), 367-380.More infoAbstract: The main factors affecting environmental sensitivity to degradation are soil, vegetation, climate and management, through either their intrinsic characteristics or by their interaction on the landscape. Different levels of degradation risks may be observed in response to particular combinations of the aforementioned factors. For instance, the combination of inappropriate management practices and intrinsically weak soil conditions will result in a severe degradation of the environment, while the combination of the same type of management with better soil conditions may lead to negligible degradation. The aim of this study was to identify factors and their impact on land degradation processes in three areas of the Basilicata region (southern Italy) using a procedure that couples environmental indices, GIS and crop-soil simulation models. Areas prone to desertification were first identified using the Environmental Sensitive Areas (ESA) procedure. An analysis for identifying the weight that each of the contributing factor (climate, soil, vegetation, management) had on the ESA was carried out using GIS techniques. The SALUS model was successfully executed to identify the management practices that could lead to better soil conditions to enhance land use sustainability. The best management practices were found to be those that minimized soil disturbance and increased soil organic carbon. Two alternative scenarios with improved soil quality and subsequently improving soil water holding capacity were used as mitigation measures. The ESA were recalculated and the effects of the mitigation measures suggested by the model were assessed. The new ESA showed a significant reduction on land degradation.
- Subramani, J., & Martin, E. (2012). Effects of Every Furrow Irrigation vs. Every Other Furrow Irrigation in Cotton. Appl. Eng. Ag. ASABE, 28(1), 39-42.
- Subramani, J., & Martin, E. C. (2012). Effects of every furrow vs. every other furrow surface irrigation in cotton. Applied Engineering in Agriculture, 28(1), 39-42.More infoAbstract: In 2001, the Arizona Department of Water Resources implemented an agricultural Best Management Practice (BMP) program. The program was designed to encourage the use of BMPs in irrigation with the goal of increasing the efficient use of water resources on the farm. Several BMPs were identified through meetings with stakeholders, researchers, and scientists. One of the BMPs identified was alternate furrow irrigation. This three-year study was designed to determine the impact of alternate furrow irrigation on surface irrigation water applications and cotton yield. There were two treatments, every furrow (EF) and every other furrow (EOF). Lint yields were 1794 and 1694 kg/ha in 2006; 1795 and 1902 kg/ha in 2007; and 1365 and 1237 kg/ha in 2008 for the EF and EOF treatments, respectively. Seasonal irrigation water applications were 187.7 and 162.3 cm in 2006; 151.4 and 137.2 cm in 2007; and 184.1 and 132.6 cm in 2008 for EF and EOF treatments, respectively. The results indicate that an average of 30.5 cm of water can be saved by the implementation of an alternate furrow irrigation scheme without significantly reducing lint yield. © 2012 American Society of Agricultural and Biological Engineers.
- Basso, B., Sartori, L., Bertocco, M., Cammarano, D., Martin, E. C., & Grace, P. R. (2011). Economic and environmental evaluation of site-specific tillage in a maize crop in NE Italy. European Journal of Agronomy, 35(2), 83-92.More infoAbstract: The integration of site-specific management principles and conservation tillage practices is a rather unexploited field of research despite their economical and environmental benefits. The objectives of this research were: (1) to investigate the farm economic net return of three conservation tillage practices (NIT - Non-Inversion Tillage, MT - Minimum Tillage and NT - No-Tillage) performed at variable intensity within predefined management zones; the HS - area with a consistently higher yield and LS - area with a consistently low yield, of a maize (Zea mays, L.) field in NE-Italy (2) to identify the most economically sound tillage practice for each management zone using long-term simulation results; (3) to assess the environmental impact of the three tillage systems with regards to soil organic carbon changes, CO2 losses and nitrate leaching using the SALUS model.Field trials were carried out on an 8-ha flat field, situated near Rovigo, NE Italy, on maize (Z. mays, L.). The farm gross margin was higher for NT in the year of study as well as the long-term simulated scenarios that resulted in higher yields over time. The NT tillage practices resulted in higher economic return in the both the HS and LS areas. Total soil carbon was higher in NT due to the crop residues retained on the surface. Nitrate leaching was higher in for the MT and for the LS area. © 2011 Elsevier B.V.
- Basso, B., Sartori, L., Bertocco, M., Cammarano, D., Martin, E., & Grace, P. (2011). Economic and environmental evaluation of site-specific tillage in a maize crop in NE Italy. Europ. J. Agronomy, 35, 83-92.
- Martin, E. C., Sriboonlue, S., Basso, B., & Subramani, J. (2011). Dairy manure impact on soil phosphorous, Nitrogen, and salt accumulation in an oat-maize rotation in Southwestern United States. Applied Engineering in Agriculture, 27(1), 87-95.More infoAbstract: The effect of manure applications on crop yield and the soil environment is becoming an ever more important issue in Arizona, where dairy herds are increasing and crop acreage is being lost to tile roofs. A field study was initiated in Central Arizona to evaluate the impact of dairy manure applications on soil phosphorus, nitrogen and salt levels after four seasons of an oat/maize rotation. Additionally, the applicability of Natural Resource Conservation Service's (NRCS) Phosphorus Index (P-Index) tool was assessed. An inorganic fertilizer treatment was used as a control. Nitrogen (N)-based rate applications of dairy manure took place semi-annually to an oat (fall) and maize (spring) rotation for four consecutive cropping seasons from 2002 through 2004. After two years and four cropping seasons, treatment effects on soil nitrate (NO 3-N) levels were evident only in the top 0.3 m and concentrations never exceeded 10 mg kg-1. The salt content of the soil also increased, with electroconductivity (EC) values nearly doubling at many depths. Manured treatments, both composted and fresh, generally produced lower crop yields than control treatment, although differences were significant in only one season for each crop. Phosphate (PO4-P) levels in the soil (0 to 2.1 m depth) increased dramatically in the compost and manure treatments from 233 to 583 and 182 to 580 kg PO4-P ha-1, respectively. Phosphate levels in the control treatment increased only 86 kg ha-1 during the same time period from 28 to 114 kg ha-1. From an agronomic standpoint, the amount of PO4-P in the manure and compost treatments was beyond the optimum requirement for crop growth and created a potential environmental hazard for the loss of phosphorus (P) due to erosion and runoff. However, when applying the NRCS P-Index tool to this field to determine the potential risk of the movement of P offsite, it was found that no restriction would be imposed on the application of any fertilizer (organic or inorganic) because the P-threshold level would not have been met. These results may indicate a need to adjust the P-Index presently used in Arizona.
- Martin, E. C., & Livingston, D. M. (2010). Drip irrigation on the Navajo Nation. ASABE - 5th National Decennial Irrigation Conference 2010, Held in Conjunction with Irrigation Show 2010, 2, 926-939.More infoAbstract: Water supply and conveyance on the Navajo Nation is limited and many people are required to haul water for daily use from collection points. There are also large areas where electricity is not available. Simple drip irrigation systems offer an efficient water use solution for the cultivation of limited amounts of crops in rural areas without the need for a mainline water or electrical power supply. This paper discusses several systems that have been installed throughout the Navajo Nation over the past 5 years. The original project, a two-year study, was initiated in 2005 at the Hubbell Trading Post, a National Park Historic Site, located in Ganado, Arizona. Drums filled with water supplied from a newly installed irrigation pipeline were used to feed low-pressure drip tape by gravity flow, in order to cultivate native corn. This system was followed by similar drip systems in Canyon del Muerto, Canyon de Chelly, Dine' College and in Luepp Arizona. In all cases, local residents took the initiative to install and maintain the drip systems.
- Martin, E. C., Schuch, U., Subramani, J., & Tilak, M. (2010). Crop coefficients for Arizona landscape trees. ASABE - 5th National Decennial Irrigation Conference 2010, Held in Conjunction with Irrigation Show 2010, 2, 984-992.More infoAbstract: Water use of many landscape plants is not only a factor of how much water a plant needs, but rather how much it receives. Previous research has found that desert-adapted trees such as live oak, once thought to be a low water user, will readily consume several times the quantity of water considered necessary for such a plant. Knowing the actual amount of water a particular tree species needs to survive or to grow to mature size will be helpful in applying irrigation water more judiciously. This information will help landscape managers and managers of water to increase the water use efficiency. In times of water shortage, the actual minimum, rather than the estimated minimum water requirements can be applied to maintain functionality of established landscape trees. Applying less irrigation water than required to achieve maximum growth can also be helpful in reducing plant maintenance such as pruning. The objectives of this project were to determine how nine species of commonly grown trees in southwestern semi-arid landscapes perform regarding growth and quality when irrigated to allow 30%, 50% or 70% depletion of available water in the soil. Results from this study will help to determine safe levels of soil water depletion to ensure growth and functionality. Data was collected on soil moisture and when combined with local weather data, resulted in the development of crop coefficients for three species of trees considered high, medium, or low water use.
- Subramani, J., & Martin, E. C. (2010). Assessing irrigation BMP for water conservation - alternate row irrigation. American Society of Agricultural and Biological Engineers Annual International Meeting 2010, 4, 3325-3332.More infoAbstract: In 2001, the Arizona Department of Water Resources implemented an agricultural Best Management Practice (BMP) program. The program was designed to encourage the use of BMPs in irrigation with goal of increasing the efficient use of water resources on the farm. Several BMPs were identified through stakeholder meetings and meeting with researchers and scientists. One of the BMPs identified was alternate row irrigation for surface irrigation systems. This study was designed to determine the impact of alternate row irrigation on irrigation water applications and yield. There were two treatments, every row (ER) and every other row (EOR). Lint yield was 1652 kg/ha (1474 lb/ac) and 1611 kg/ha (1438 lb/ac) in 2006; 1795 kg/ha (1603 lb/ac) and 1902 kg/ha (1698 lb/ac) in 2007 and 1365 kg/ha (1219 lb/ac) and 1237 kg/ha (1104 lb/ac) in 2008 for the ER and EOR treatments, respectively. The irrigation water amounts were 187.7 cm and 162.3 cm (73.9 and 63.9 in.) in 2006; 151.4 and 137.2 cm (59.6 and 54.0 in.) in 2007 and 184.1 and 132.6 cm (72.5 and 52.2 in.) in 2008 for the ER and EOR treatments respectively. The results indicate that on an average the use of EOR saves about 30.5 cm (12 in.) of water.
- Subramani, J., Martin, E. C., & Andrade-Sanchez, P. (2010). Assessing irrigation BMP for water conservation - Land leveling. American Society of Agricultural and Biological Engineers Annual International Meeting 2010, 4, 3333-3343.More infoAbstract: In 2001, the Arizona Department of Water Resources implemented an agricultural Best Management Practice (BMP program). The program was designed to encourage the use of BMP in irrigation with goal of increasing efficient use of water resources on the farm. Several BMP were identified through stakeholder meetings and meeting with researchers and scientists. One of the BMPs identified was annual laser touchup to maintain a level field slope. This study was designed to determine the impact of yearly laser leveling on irrigation water applications and yield. There were two treatments, no laser leveling and laser leveled. There were no significant differences due to leveling for yield in any of the three years. Lint yield for no laser leveling and laser leveled treatments was 2010 and 1990 kg/ha (1795 and 1777 lb/ac) in 2006, 1780 and 1829 kg/ha (1589 and 1633 lb/ac) in 2007, and 1564 and 1687 kg/ha (1397 and 1507 lb/ac) in 2008 respectively. The amount of water irrigated was 167.6 cm (66 inches) for no laser leveled vs. 154.9 cm (61 inches) for laser leveled in 2007, and 226.1 and 154.9 cm (89 and 61 inches) in 2008.
- Bertocco, M., Basso, B., Sartori, L., & Martin, E. C. (2008). Evaluating energy efficiency of site-specific tillage in maize in NE Italy. Bioresource Technology, 99(15), 6957-6965.More infoPMID: 18304805;Abstract: This paper examine the efficiency of energy use of three conservation tillage practices (SST - sub-soil tillage; MT - minimum tillage; and NT - no tillage) performed within two management zones, previously identified in a field according to the stability of yield variability. Experiments were carried out in 2003 in NE Italy, on a farm near Rovigo, on a 8-ha field with clay soil, in maize (Zea mays, L.). The purpose of the paper is (i) to investigate the energy variability due to these tillage practices performed spatially within two management zones and (ii) to analyze the long-term energetic efficiency for each tillage practice. The energy balance was highest for SST with respect to MT and NT, due to labor and fuel consumption rates. The energy balance was influenced by the spatial pattern of yield, with appreciable differences between practices in terms of both the conversion index of energy for tillage (9.0, 12.6 and 22.8 GJ ha-1 for SST, MT and NT, respectively) and the energy use efficiency for tillage (8.0, 11.6, 21.8 GJ ha-1 for SST, MT and NT, respectively). Based on the simulated data and the calibration results, SALUS model proved to be a good tool for analyzing long-term effects of tillage practices on yield. The NT treatment showed the best efficiency over years, due to the low inputs in comparison with the output level. © 2008 Elsevier Ltd. All rights reserved.
- Basso, B., Bertocco, M., Sartori, L., & Martin, E. C. (2007). Analyzing the effects of climate variability on spatial pattern of yield in a maize-wheat-soybean rotation. European Journal of Agronomy, 26(2), 82-91.More infoAbstract: The identification of homogeneous management zones within a field is crucial for variable rate application of agronomic inputs. This study proposed a methodology to identify homogeneous management zones within a 8 ha field, based on the stability of measured and simulated yield patterns in a maize-soybean-wheat crop rotation in north-east Italy. Crop growth and yield were simulated over a 14-year period (1989-2002) using CERES-Maize, CROPGRO-Soybean and CERES-Wheat models to account for weather effects on yield spatial patterns. The overlay of long-term assessments of yield spatial and temporal data allowed for the identification of two stable zones with different yield levels, one with greater yield (called HS for high and stable yield) and one with lower yield (called LS for low and stable yield). The size of the HS zone identified using 14 years of simulated yield was smaller than the one obtained when considering only yield monitor data taken during the 5-year crop rotation. The LS zone was larger when using simulated data, confirming that the consistency of temporal stability increased by increasing the years considered. The models were able to closely simulate yield across the field when site-specific inputs were used, showing potential for use in yield map interpretation in the context of precision agriculture. Results showed that a combination of GIS tools and crop growth simulation models can be used to identify temporally stable zones, which is a fundamental prerequisite for adopting variable rate technologies. © 2006 Elsevier B.V. All rights reserved.
- Ogle, T. D., Gustafson, R. J., Pickett, L. K., Martin, E. C., Hughs, S. E., Reinemann, D. J., Erbach, D. C., Hahn, R. H., Brodbeck, K. N., Smith, D. W., & Graves, R. E. (2007). Ten agricultural and biological engineering achievements that changed the world. Resource: Engineering and Technology for Sustainable World, 14(4), 2-7.More infoAbstract: Some of the agricultural and biological engineering achievements that has changed the world are presented. Agricultural engineers have been intimately involved in the development of the agricultural tractor and associated implements. Tractors have changed tremendously over the years with more power heated and air conditioned cabs with stereos, power shift transmissions, front wheel assist, guidance systems, infinite variable transmissions, and computers. The electrification of rural America has enabled the switch from animal and human power to mechanical and electrical power. One of the most versatile of farm machines, the combine, harvests a diverse range of crops, handling dry fragile crops such as flax, tall rugged crops such as corn, and stringy crops often flattened to the ground such as rice. The development of the milking machine in the early 1900s has improved the labor efficiency of collecting milk.
- Tanksley, K. A., Slack, D. C., Martin, E. C., & Basso, B. (2006). Effects of fresh and composted dairy manure applications on alfalfa yield and the environment in Arizona. Agronomy Journal, 98(1), 80-84. doi:10.2134/agronj2005.0039More infoThe Unified Animal Feeding Operation Strategy requires that field application of animal waste, a common fertilization and disposal practice, may not exceed crop nutrient needs. Additional guidelines set forth by the Arizona Department of Environmental Quality state that animal waste applications on agricultural fields in designated Confined Animal Feeding Operations (CAFOs) must be made in a manner such that the total N applied to the field cannot exceed the uptake from the crop grown. Because alfalfa is grown year round and can take up large quantities of N, many operators of CAFOs apply animal waste to their production alfalfa fields as method of waste disposal. In this research, fresh and composted dairy manure was applied to plots in a production alfalfa (Medicago sativa L.) field to determine the impact on alfalfa yield, soil nitrogen (N), phosphorus (P), and electrical conductivity (EC) levels and the potential for nitrate (NO3) and phosphate (PO4) leaching. Unfertilized plots were maintained as controls. Fresh and composted manure was applied to fertilized plots after each harvest at a rate intended to replace N removed from the previous cutting. After 1.5 yr and 13 cuttings, soil analysis down to 150 cm depth showed no significant difference in soil N between treatments. At study end, NO3–N made up 1.1% of total N in the fertilized plots but only 0.6% in control plots. Changes in soil N were not significant. Soil P content increased in fertilized plots but remained stable in control plots. Final soil PO4 measurements were 16, 99, and 116 kg ha 21 in the control, manure-treated, and compost-treated plots, respectively. Leachate from three drainage lysimeters contained no detectable NO3 or PO4 from any of the treatments. LSD showed no difference in EC between the beginning and the end of study, and alfalfa yield did not vary among treatments.
- Martin, E. C., & Jai, X. (2000). Evaluation of Dew Point Temperature as an Indicator of Aridity for Weather Collection Sites in Arizona. 2000 ASAE Annual Intenational Meeting, Technical Papers: Engineering Solutions for a New Century, 2, 1855-1864.More infoAbstract: Integral to every farm management scheme is reliable weather data. These data become even more important in irrigated agriculture where daily fluctuations in temperature, solar radiation and relative humidity can have even a greater impact on scheduling the next irrigation. However, in collecting these weather parameters, one must be cognizant of the location where the weather data are collected. In Arizona, the AZMET network consists of 25 weather stations located throughout the state's agricultural regions collecting hourly data on temperature, solar radiation, relative humidity and wind. These data are used for a variety of purposes, including the computation of reference evapotranspiration (ETo) for use with irrigation scheduling. In order to properly compute ETo, the weather station must be placed in a well-irrigated site with sufficient fetch. To assure that the station is collecting reliable data, it has been suggested that a comparison between dew point temperature and minimum temperature be done. If the minimum temperature does not approach the dew point temperature (± 3°C), the site may be too arid, and the data should then be adjusted. However, in Arizona, with its natural occurring aridity, this criterion may not be valid since even under the most ideal conditions, the minimum temperature is well above the dew point temperature. In this paper, we exam the use of this criterion for Central Arizona.
- Martin, E. C., & Vinson, J. (2000). Use of Radio Telemetry and Capacitance Probes to Monitor Soil Moisture. 2000 ASAE Annual Intenational Meeting, Technical Papers: Engineering Solutions for a New Century, 2, 1845-1854.More infoAbstract: Utilizing capacitance probes (C-Probes) in conjunction with radio telemetry, soil moisture was monitored in a cotton field and an alfalfa field in Maricopa, Arizona. Once installed, the data collected by the C-Probes were interrogated every 15 minutes and automatically downloaded by a base station located at a site nearby. The base station, which was connected to a desktop computer, could then be activated to download the data into the computer where the data could be viewed. In addition to the C-Probe data, neutron moisture probe access tubes were also installed at the sites and soil moisture readings taken. The data were compared over several months. When comparing discrete soil moisture values, i.e., values at a particular depth, the C-Probes were not in agreement with the neutron probe readings. However, when comparing soil moisture over a meter depth, or comparing water use data, the C-Probe and neutron probe data compared well. The theory behind this discrepancy is that the C-Probe only measured a discrete soil volume whereas the neutron probe samples a much larger volume. At any particular depth, the comparison may be poor because the two instruments are measuring two separate soil regions. However, when comparing a larger soil volume, the two measurements were in agreement.
- Rasse, D. P., Ritchie, J. T., Wilhelm, W. W., Wei, J., & Martin, E. C. (2000). Simulating inbred-maize yields with CERES-IM. Agronomy Journal, 92(4), 672-678.More infoAbstract: CERES-Maize, which was designed for simulation of hybrid maize (Zea mays L.), cannot be applied directly to seed-producing inbred maize because of specific field operations and physiological traits of inbred maize plants. We developed CERES-IM, a modified version of CERES-Maize 3.0 that accommodates these inbred-specific operations and traits, using a set of phenological measurements conducted in Nebraska (NE), and further tested this model with a set of field data from Michigan (MI). Detasseling (i.e., removal of the tassels from the female plants) was conducted prior to silking. Male rows were removed approximately 10 d following 75% silking. The thermal time from emergence to the end of the juvenile phase (P1) and the potential number of kernels per plant (G2) were assessed from field data, and were the only two coefficients allowed to vary according to the inbred line. Rate of leaf appearance of the inbreds was accurately simulated using a measured phyllochron interval of 54 degree-days (°Cd). Simulation of detasseling and male-row removal improved grain yield simulation for inbreds. For a set of 35 inbred-site-year simulations, the model simulated grain yield with satisfactory accuracy (RMSE = 429 kg ha-1). Average grain yields were 4556 and 4721 kg ha-1 for the measured and simulated values, respectively. CERES-IM simulations suggest that the effect of male-row removal on grain yield is extremely sensitive to the precise date at which this operation is conducted. This would explain the inconsistent effect of male-row removal on female grain yields reported in the literature.
- Rasse, D. P., Ritchie, J. T., Peterson, W. R., Loudon, T. L., & Martin, E. C. (1999). Nitrogen management impacts on yield and nitrate leaching in inbred maize systems. Journal of Environmental Quality, 28(4), 1365-1371.More infoAbstract: Little information is available regarding N management of inbred maize (Zea mays L.), which exports less N than hybrid maize. Nitrate contamination of the groundwater has been a concern in St Joseph County in southwest Michigan where >20 000 ha of seed maize are grown on sand and sandy loam soils. Over application of N fertilizer potentially reduces profits of the local growers and poses a threat to the environment. A field experiment was conducted from 1990 to 1994 to estimate N fertilizer requirements of three different inbred varieties for maximizing yields while minimizing ground water pollution. Yield and N content of grain and stover were analyzed at the end of each growing season. Nitrate leaching was monitored throughout the 5 yr of study by collecting and analyzing drainage flows out of five large field lysimeters. Grain yield was the least responsive to N fertilization, compared with stover biomass, and grain and stover N concentrations. Analyses of yield, NO3-N leaching and soil N balance indicated that the appropriate fertilization of the P38 mid-season inbred approximated 108 kg N ha-1. Nitrate leaching out of unfertilized plots reached a threshold of 12 to 15 kg N ha-1 yr-1, during the last 2 yr of treatment. Application of 101 and 202 kg N ha-1 generated an average annual loss of 26 and 60 kg N ha-1, respectively, during the last 2 yr of treatment.
- Martin, E. (1997). Overcoming the language barrier. Resource: Engineering and Technology for Sustainable World, 4(10), 7-8.More infoAbstract: Extension faculty at the University of Arizona was organized recently. The faculty uses the traditional approach to present information at extension meetings to reach the irrigators. A grant from the Arizona Department of Water Resources allowed specialists and county agents to buy translating equipment to initiate bilingual workshops. It is necessary for people whose primary language is Spanish.
- Waller, P. M., Slack, D. C., Martin, E. C., & Hla, A. K. (1997). HEAT UNIT-BASED CROP COEFFICIENT FOR GRAPEFRUIT TREES. Applied Engineering in Agriculture, 13(4), 485-489. doi:10.13031/2013.21632More infoThe onset and rate of sap moving up the branches of grapefruit (Citrus paradisi Macfadyen) trees were monitored hourly using portable sap flow sensors at Waddell, Arizona. Hourly reference evapotranspiration (ETo) estimates were calculated using data from a nearby weather station. Crop water use was estimated from soil moisture measurements using a neutron probe. These data were used to first delineate the upper and lower temperature threshold values for the determination of heat units. A heat unit-based crop coefficient was then derived from a correlation of the crop coefficient with heat units over a crop year. The heat unit-based crop coefficient was found to be similar to crop coefficients derived by other researchers.
- Martin, E. C., Ritchie, J. T., & Baer, B. D. (1996). Assessing investment risk of irrigation in humid climates. Journal of Production Agriculture, 9(2), 228-233.More infoAbstract: Michigan has an estimated 475 000 acres of irrigated land. The irrigation is used to supplement seasonal rainfall during short periods of drought. Many row crops such as corn (Zea mays L.), soybeans [Glycine max (L.) Merr.], potatoes (Solanum tuberosum L.), and dry beans (Vicia faba L.) are under sprinkler irrigation systems. Much of the tree fruit acreage is also irrigated, using mainly drip/trickle systems. Though irrigation usually results in higher yields and income, it is possible that the expense of owning and operating an irrigation system outweighs income benefits if calculated over several years. The Irrigation Cost Analysis Program (ICAP) has been designed as a tool for assessing the risk associated with investing in an irrigation system for corn production. Using inputs such as purchase price, annual finance rate, production costs for irrigated and nonirrigated crops (e.g., fertilizer, seed, fuel, etc.), yield related costs, and irrigation costs, a user gains insight into the factors affecting the profitability and risk of such an investment. Using the validated CERES-Maize growth simulation and water balance model in conjunction with weather, management, and economic data, ICAP provides estimates on 30 yr net profit for irrigated and nonirrigated corn crops, and the increase in yield necessary to pay the increased costs.
- Martin, E. C., Loudon, T. L., Ritchie, J. T., & Werner, A. (1994). Use of drainage lysimeters to evaluate nitrogen and irrigation management strategies to minimize nitrate leaching in maize production. Transactions of the American Society of Agricultural Engineers, 37(1), 79-83.More infoAbstract: Increasing public awareness of nitrate contamination of groundwater has caused agriculturalists to focus their attention on nitrogen recommendations and management strategies. In Michigan the problem of nitrate contamination of groundwater is pervasive. Using drainage lysimeters placed in a grower's field, a conventional nitrogen fertilizer and irrigation strategy was compared with a conservative research strategy for impact on yield and nitrate leaching in maize (Zea mays L.) production. The conventional nitrogen fertilizer strategy was to apply 178 kg N ha-1 preplant as anhydrous ammonia and then some additional N in the starter fertilizer. Irrigation water applications for the conventional strategy were based on an irrigation scheduling program and the physical limitations of the existing center pivot system. The research strategy was to use split applications of nitrogen fertilizer and to apply irrigation water based on daily crop requirements. The research plot was outside of the influence of the grower's irrigation system and had its own dedicated irrigation system which provided flexibility in the timing and amount of water applied. The two strategies resulted in similar yields for two seasons. However, the conventional plot received an additional 89 kg N/ha-1 (preplant) in the first year due to operator error. During the first 24 months, the total drainage from the conventional strategy was 190 mm more than the research strategy and the nitrate leached was 170 kg N ha-1 more. In the third year of the study, the preplant application of the conventional strategy was deleted and only 9 kg N ha-1 was applied in the starter fertilizer. This was done to study the ability of maize to mine the soil nitrogen and reduce nitrate leaching. The research strategy was continued as in years past. Though only 9 kg N ha-1 of nitrogen were applied to the conventional plot, the grain yield was 4445 kg ha-1 and the nitrate leaching was reduced to 43 kg N ha-1 over an eight-month period. That represented a reduction in nitrate leaching of 60% as compared to the same time period in the previous year. This study has shown the usefulness of drainage lysimeters in evaluating nitrogen and irrigation management strategies in respect to soil water drainage and nitrate leaching. Additionally, the collection of data throughout the year provides greater insight into non-growing season drainage, showing that most nitrate loss occurs between the harvest date and the subsequent planning date.
- Martin, E. C., Shayya, W. H., Bralts, V. F., Loudon, T. L., & Johnson, J. A. (1990). Irrigation scheduling. A statewide program in Michigan. ASAE Publication, 700-706.More infoAbstract: In 1988, the Legislature of the State of Michigan used energy overcharge funds to create the Michigan Energy Conservation Program for Agriculture and Forestry (MECP).This three year (1988-1990) program was designed to assist Michigan farmers and forestry products producers to identify and adopt management practices which will conserve energy and save them money. The program was implemented through a multi-agency effort. The purpose of this paper is to describe the statewide Irrigation Management and Scheduling Program and the inter-agency cooperation that was required for a successful irrigation management program including the dvelopment and maintenance of new linkages. After two years, the MECP project has proven to be very successful.
- Martin, E. C., Ritchie, J. T., Reese, S. M., Loudon, T. L., & Knezek, B. (1988). Large-area, lightweight rainshelter with programmable control. Transactions of the American Society of Agricultural Engineers, 31(5), 1440-1444.More infoAbstract: A rainshelter facility, which covers 0.13 ha, has been constructed at the Kellogg Biological Station of Michigan State University for the study of plant growth response to soil water deficit. The facility consists of two buildings which run on a single drive system. The buildings are located at opposite ends of a set of tracks and move toward each other during rainfall. The ends of the buildings which face one another are open so that when the buildings meet in the center, they enclose the entire test plot. Once the buildings cover the plot, ventilation is provided by openings at the base of the walls and by a 17.8 cm (7 in.) wide lateral opening that runs the full length of the ridge of each building's roof. A programmable controller governs the movement of the buildings and performs constant checks on the system's status.
- Reese, S., Loudon, T., & Martin, E. (1986). PROGRAMMABLE CONTROLLER TO OPERATE A DUAL BUILDING RAINOUT SHELTER.. Paper - American Society of Agricultural Engineers.More infoAbstract: A rainout shelter is a structure or structures designed to be moved over a test plot area of a field in the event of rainfall to prevent the natural rain from reaching the test plot. A commercial programmable motor controller was installed at the Michigan State University Kellogg Biological Station Rainout Shelter Facility to control the motion of the shelter automatically. The controller accepts input from a tipping bucket rain gauge to determine when to close or open the shelter.
- Martin, E. C., Ritchie, J. T., & Loudon, T. L. (1985). USE OF THE CERES-MAIZE MODEL TO EVALUATE IRRIGATION STRATEGIES FOR HUMID REGIONS.. ASAE Publication, 342-350.More infoAbstract: The purpose of this investigation was to illustrate how a computerized simulation of corn growth and water use can be used in analyzing the effects of varying irrigation strategies on various water balance parameters. A yield analysis was also performed.
- Subramani, J., Martin, E. C., & Andrade-sanchez, P. (2010). Assessing Irrigation BMP for Water Conservation - Land Leveling. In 2010 Pittsburgh, Pennsylvania, June 20 - June 23, 2010.More infoIn 2001, the Arizona Department of Water Resources implemented an agricultural Best Management Practice (BMP program). The program was designed to encourage the use of BMP in irrigation with goal of increasing efficient use of water resources on the farm. Several BMP were identified through stakeholder meetings and meeting with researchers and scientists. One of the BMPs identified was annual laser touchup to maintain a level field slope. This study was designed to determine the impact of yearly laser leveling on irrigation water applications and yield. There were two treatments, no laser leveling and laser leveled. There were no significant differences due to leveling for yield in any of the three years. Lint yield for no laser leveling and laser leveled treatments was 2010 and 1990 kg/ha (1795 and 1777 lb/ac) in 2006, 1780 and 1829 kg/ha (1589 and 1633 lb/ac) in 2007, and 1564 and 1687 kg/ha (1397 and 1507 lb/ac) in 2008 respectively. The amount of water irrigated was 167.6 cm (66 inches) for no laser leveled vs. 154.9 cm (61 inches) for laser leveled in 2007, and 226.1 and 154.9 cm (89 and 61 inches) in 2008.
- Schuch, U. K., Martin, E. C., & Nair, S. (2014, 10/21). Landscape trees under permanent drought.. Tree Irrigation Field Day. Maricopa Ag. Center, Maricopa, AZ. Maricopa, AZ.
- Schuch, U. K., Martin, E. C., Subramani, J., & Mahato, T. (2013, July). Performance of Landscape Trees in the Semi-Arid Southwest under Three Irrigation Regimes. ASHS Annual Conference. Palm Desert, CA: American Society for Horticultural Sciences.
- Martin, E. C. (2012, August). Sustainable irrigation practices. Western SARE Update. Santa Fe, NM: Western SARE.
- Martin, E. C. (2011, April). Drip Irrigation. Chinle and Ft. Defiance on the Navajo Nations: Navajo Nation.
- Martin, E. C. (2011, January). Presentation to Wyoming Growers Association. Wyoming Growers Association. Maricopa, AZ: Wyoming Growers Association.
- Martin, E. C. (2011, July). Drip Irrigation for youth. Fort Huachuca, AZ.