Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 26 of 26
Full-Text Articles in Life Sciences
Improving Decision Support Systems With Machine Learning: Identifying Barriers To Adoption, Skye Brugler, Maaz Gardezi, Ali Dadkhah, Donna M. Rizzo, Asim Zia, Sharon A. Clay
Improving Decision Support Systems With Machine Learning: Identifying Barriers To Adoption, Skye Brugler, Maaz Gardezi, Ali Dadkhah, Donna M. Rizzo, Asim Zia, Sharon A. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Precision agriculture (PA) has been defined as a “management strategy that gathers, processes and analyzes temporal, spatial and individual data and combines it with other information to support management decisions according to estimated variability for improved resource use efficiency, productivity, quality, profitability and sustainability of agricultural production.” This definition suggests that because PA should simultaneously increase food production and reduce the environmental footprint, the barriers to adoption of PA should be explored. These barriers include: 1) the financial constraints associated with adopting DSS, 2) the hesitancy of farmers to change from their trusted advisor to a computer program often behaves …
Soybean Management For Seed Composition: The Perspective Of U.S. Farmers, Andre F. Borja Reis, Luiz Rosso, Dan Davidson, Peter Kovacs, Larry C. Purcell, Frederick E. Below, Shaun Casteel, Hans J. Kandel, Seth Naeve, Sotirios V. Archontoulis, Ignacio A. Ciampitti
Soybean Management For Seed Composition: The Perspective Of U.S. Farmers, Andre F. Borja Reis, Luiz Rosso, Dan Davidson, Peter Kovacs, Larry C. Purcell, Frederick E. Below, Shaun Casteel, Hans J. Kandel, Seth Naeve, Sotirios V. Archontoulis, Ignacio A. Ciampitti
Agronomy, Horticulture and Plant Science Faculty Publications
The soybean [Glycine max (L.) Merr.] compositional quality is mainly provided by the seed concentration of protein and oil. These traits are critical for sustaining global use, and although there is demand for high protein soybean, no mechanism to differentiate production is in place. At the opposite end of the supply chain, farmers are remunerated on a mass basis without having any incentive regarding seed composition. This study evaluated farmers' perspectives and knowledge on soybean quality and their propensity to adopt quality improvement technologies. Farmers from the main U.S. producing regions (n = 271) were investigated with a …
The Custom Service Industry's Role In Precision Agriculture Adoption: A Literature Review, Scott W. Fausti, Bruce Erickson, David Clay, Sharon Clay
The Custom Service Industry's Role In Precision Agriculture Adoption: A Literature Review, Scott W. Fausti, Bruce Erickson, David Clay, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
This literature review focuses on the role of the precision agriculture (PA) custom services industry in facilitating farmer adoption of PA technology. Based on the review, a series of stylized facts are developed that characterize the custom services industry's role in the PA adoption process in the United States. The literature suggests that increasing the availability of custom services in local agricultural production markets will positively influence the rate of PA adoption. Recent PA custom services industry field surveys, however, indicate that skilled labor, proficient in PA technology, is critical to develop and provide custom services needed to increase the …
Is The Custom Service Industry's Role In Precision Agriculture Linked To Workforce Development?, Scott W. Fausti, Bruce Erickson, David Clay, Sharon Clay
Is The Custom Service Industry's Role In Precision Agriculture Linked To Workforce Development?, Scott W. Fausti, Bruce Erickson, David Clay, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Retail dealership survey data suggests that the lack of a qualified precision agriculture (PA) workforce limits the ability of the PA service industry to provide technological knowledge and services to producers who have adopted PA technology. The key empirical findings suggest that retail dealerships have the greatest difficulty finding workers who have, a) the capability to operate and collect data using specialized PA technology, b) the capability to interpret and develop management strategies using PA generated data, and c) a basic generalized competency in PA technology and its applications. The perceived shortage of skilled workers suggests that there is a …
Conservation Agriculture For Food Security And Climate Resilience In Nepal, Deepak R. Joshi, Rajan Ghimire, Tulsi Kharel, Umakant Mishrra, Sharon A. Clay
Conservation Agriculture For Food Security And Climate Resilience In Nepal, Deepak R. Joshi, Rajan Ghimire, Tulsi Kharel, Umakant Mishrra, Sharon A. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Achieving the sustainable development goals of the United Nations requires innovations in agriculture and development of climate-smart and economically feasible approaches for smallholder farmers in developing countries. Historical climate data of Nepal, which include 116 yr since 1901, has shown an increasing trend for average temperature by 0.016 ˚C yr–1 whereas precipitation has shown a decreasing trend by 0.137 mm yr–1. Such weather trends could enhance glacier melt associated flooding, and delayed monsoon rainfalls negatively impacting the agricultural production. The Nepalese government is promoting conservation agriculture (CA) through development of low-cost technologies that can be used effectively in difficult terrains. …
Moran Eigenvector Filtering Of Multi-Year Yield Data With Application To Zone Development, Dan S. Long, Daniel A. Griffith, Craig K. Kvien, David E. Clay
Moran Eigenvector Filtering Of Multi-Year Yield Data With Application To Zone Development, Dan S. Long, Daniel A. Griffith, Craig K. Kvien, David E. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
A time‐series of yield monitor data may be used to identify field areas of consistently low or high yield to serve as productivity zones for site‐specific crop management. However, transient factors that affect yield in 1 yr, but not every year, detract from this approach. The objective of this study was to illustrate Moran eigenvector spatial filtering (MESF) with results from analysis of multi‐year crop yield data from two farm fields in the United States. The MESF method accounts for temporal autocorrelation within a common factor map representing the correlation across years and partitions stochastic geographic variation into spatially structured …
Abrasive Weeding As A Vehicle For Precision Fertilizer Management In Organic Vegetable Production, Tran Kim Ngan Luong, Frank Forcella, Sharon A. Clay, Michael S. Douglass, Sam E. Wortman
Abrasive Weeding As A Vehicle For Precision Fertilizer Management In Organic Vegetable Production, Tran Kim Ngan Luong, Frank Forcella, Sharon A. Clay, Michael S. Douglass, Sam E. Wortman
Agronomy, Horticulture and Plant Science Faculty Publications
Abrasive weeding is a nonchemical weed control tactic that uses small, gritty materials propelled with compressed air to destroy weed seedlings. Organic fertilizers have been used successfully as abrasive grits to control weeds, but the goal for this study was to explore the effects of fertilizer grit, application rates, and background soil fertility on weeds, plant available nitrogen (N) uptake, and crop yield. Field trials were conducted in organic ‘Carmen’ sweet red pepper (Capsicum annuum) and organic ‘Gypsy’ broccoli (Brassica oleracea var. italica) and treatments included organic fertilizer grit (8N–0.9P–3.3K vs. 3N–3.1P–3.3K), grit application rates (low …
Fungicide, Insecticide, And Foliar Fertilizer Effect On Soybean Yield, Seed Composition, And Canopy Retention, Kelsey Bergman, Ignacio Clampitti, Peter Sexton, Péter Kovács
Fungicide, Insecticide, And Foliar Fertilizer Effect On Soybean Yield, Seed Composition, And Canopy Retention, Kelsey Bergman, Ignacio Clampitti, Peter Sexton, Péter Kovács
Agronomy, Horticulture and Plant Science Faculty Publications
Soybean [Glycine max (L.) Merr.] yield has increased over time through the introduction of new varieties and improved agronomic practices. However, seed protein concentration has decreased. We conducted field studies in 2018 and 2019 to investigate the effects of fungicide, insecticide, and foliar fertilizer application on grain yield and seed quality in two soybean maturity groups (MG). In‐season treatments targeted nutrient availability and soybean canopy duration during the seed‐filling period by fungicide, insecticide, or foliar fertilizer application at the onset of this period. Biomass samples were collected at R5, R6, and R7 and partitioned into plant parts. Year, location, …
Agronomic Response Of Camelina To Nitrogen And Seeding Rate On The Northern Great Plains, Thandiwe Nleya, Dwarika Bhattarai, Phillip Alberti
Agronomic Response Of Camelina To Nitrogen And Seeding Rate On The Northern Great Plains, Thandiwe Nleya, Dwarika Bhattarai, Phillip Alberti
Agronomy, Horticulture and Plant Science Faculty Publications
Camelina (Camelina sativa L. Crantz,) a new oilseed crop in the Brassicaceae family has favorable agronomic traits and multiple food and industrial uses. Appropriate production practices for optimal camelina yield in temperate climates of North America are lacking. This study investigated the response of camelina seed yield and quality, and agronomic traits to applied N (5 levels, 0, 28, 56, 84, 140 kg ha−1) and four seeding rates (4.5, 9, 13, 17.5 kg ha−1). Separate experiments were conducted at four environments (site-years) for N and three environments for seeding rate in South Dakota. In three of the four environments, the …
Organic Fertilizer Abrasive Grits Increase Soil Available Nitrogen, Plant Height, And Biomass, Michael Carlson, Frank Forcella, Sam Wortman, David Clay, Sharon A. Clay
Organic Fertilizer Abrasive Grits Increase Soil Available Nitrogen, Plant Height, And Biomass, Michael Carlson, Frank Forcella, Sam Wortman, David Clay, Sharon A. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
In organic cropping systems, air‐propelled abrasive grits can be used to control in‐row weeds. If the applied abrasive grit is an approved organic fertilizer, these applications may serve a dual purpose of weed control and crop fertility. Laboratory soil incubations examined the N mineralization rates of several grit types with differing C/N ratios (Agra Grit [crushed walnut shells, 170:1], corncob grit [91:1], Sustane [composted turkey litter, 5.0:1], Phytaboost Plant Food [crushed and pelletized soybean meal, 5.0:1]). A greenhouse study determined plant wheat (Triticum aestivum L.), kale (Brassica napus pabluaria DC), and velvetleaf (Abutilon theophrasti Medik.) growth response …
Management Considerations For Palmer Amaranth In A Northern Great Plains Soybean Production System, Brian Vab De Stroet, Sharon Clay
Management Considerations For Palmer Amaranth In A Northern Great Plains Soybean Production System, Brian Vab De Stroet, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Palmer amaranth (Amaranthus palmeri S. Watson) was first observed in a South Dakota field in 2015. This study assessed Palmer amaranth growth based on planting date (PD), impact on soybean [Glycine max (L.) Merr.] yield, and response of seedlings of South Dakota biotype seedlings to herbicides with different mechanisms of action (MOA). Soybean yield loss was influenced by Palmer amaranth density in 2016 (p = 0.001), with yield losses of 33% at densities greater than 15 plants m−2 (R2 = 0.65), although yield losses at low densities were greater than predicted by the fitted …
Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo
Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo
Agronomy, Horticulture and Plant Science Faculty Publications
A common restoration treatment for saline–sodic soils involves improving soil drainage, applying soil amendments (e.g., CaSO4, CaCl2, or elemental S), and leaching with water that has a relatively low electrical conductivity. However, due to high subsoil bulk densities and low drainable porosities, these treatments many not be effective in glaciated dryland systems. A 3-yr field study conducted in three model systems determined the impact of chemical amendments (none, CaCl2, CaSO4, and elemental S) on plant growth, microbial composition, temporal changes in electrical conductivity (ECe ), and the relative sodium content (%Na). …
Nitrogen Requirements Of Ethiopian Mustard For Biofuel Feedstock In South Dakota, Phillip Alberti, Shannon Osborne, Febina Mathew, Shakaut Ali, Heidi Sieverding, Sandeep Kumar, Thandiwe Nieya
Nitrogen Requirements Of Ethiopian Mustard For Biofuel Feedstock In South Dakota, Phillip Alberti, Shannon Osborne, Febina Mathew, Shakaut Ali, Heidi Sieverding, Sandeep Kumar, Thandiwe Nieya
Agronomy, Horticulture and Plant Science Faculty Publications
Ethiopian mustard (Brassica carinata A. Braun) is a non-food oilseed crop that has received attention for its potential as a low-input biofuel feedstock suitable for production in the semiarid regions of the Northern Great Plains (NGP). Because B. carinata is a new crop to the NGP, the best management practices have yet to be developed. The objective of the study was to evaluate the effects of N fertilizer rate on seed yield, seed oil concentration, and oil yield of B. carinata and to determine the economic optimum N fertilizer rates. Field studies were conducted at two locations in South …
Crop Residue Management Challenges: A Special Issue Overview, David Clay, Ronald Alverson, Jane M.F. Johnson, Douglas L. Karlen, Sharon Clay, Michael Q. Wang, Stephanie A. Bruggeman, Shaina Westhoff
Crop Residue Management Challenges: A Special Issue Overview, David Clay, Ronald Alverson, Jane M.F. Johnson, Douglas L. Karlen, Sharon Clay, Michael Q. Wang, Stephanie A. Bruggeman, Shaina Westhoff
Agronomy, Horticulture and Plant Science Faculty Publications
The amount of crop residues that can be sustainability removed is highly variable and is a function of many factors including the soil, climatic, and plant characteristics. For example, leaving an insufficient amount of crop residue on the soil surface can be detrimental for soil quality, result in loss of soil organic matter (SOM), and increase soil erosion, whereas leaving excessive amounts can impair soil-seed contact, immobilize N, and/or keep soils cool and wet. This special issue evolved as an outcome of, “Crop Residues for Advanced Biofuels: Effects on Soil Carbon” workshop held in Sacramento, CA, in 2017. The goal …
Knowledge, Skills, And Abilities In The Precision Agriculture Workforce: An Industry Survey, Bruce Erickson, Scott W. Fausti, David Clay, Sharon Clay
Knowledge, Skills, And Abilities In The Precision Agriculture Workforce: An Industry Survey, Bruce Erickson, Scott W. Fausti, David Clay, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Precision agriculture encompasses a set of related technologies aimed at better utilizing crop inputs, increasing yield and quality, reducing production risks, and enabling information flow throughout the crop supply and end-use chains. As agricultural businesses invest in precision offerings, their capacity to provide these products and services will depend on their ability to hire and retain employees with appropriate proficiency as defined in their knowledge, skills, and abilities (KSAs). A 2015 survey of agricultural retailers examined the minimum educational requirements retailers were seeking in their hires, along with the importance of a list of KSAs for the various positions that …
Propelled Abrasive Grit For Weed Control In Organic Silage Corn, Mauricio Erazo-Barradas, Fran Forcella, Dan Humburg
Propelled Abrasive Grit For Weed Control In Organic Silage Corn, Mauricio Erazo-Barradas, Fran Forcella, Dan Humburg
Agronomy, Horticulture and Plant Science Faculty Publications
Weed management in organic farming requires many strategies to accomplish acceptable control and maintain crop yields. This 2-yr field study used air propelled abrasive grit for in-row weed control in organically certified silage corn (Zea mays L.). Corncob grit was applied as a single application at corn vegetative growth stages V1 (one true leaf; numbers correspond to number of true leaves at the corn vegetative stage), V3, or V5 (in 2013) and V3, V5, and V7 (in 2014) and in double and triple combinations at these stages. Between-row weed control was accomplished by flaming or cultivation after the last grit …
Evaluating Adaptions Of Soft Red Winter Wheat In Eastern Region Of Usa, Dilmini Alahakoon, Anne Fennell, Jixiang Wu
Evaluating Adaptions Of Soft Red Winter Wheat In Eastern Region Of Usa, Dilmini Alahakoon, Anne Fennell, Jixiang Wu
Agronomy, Horticulture and Plant Science Faculty Publications
Identification of winter wheat genotypes that are highly adapted to a wide range of environmental conditions is one of the most important wheat research objectives. Multienvironment trials (METs) under diverse environments is a commonly used practice to evaluate mean performance and yield stability. However, locations used and genotypes planted may vary from year to year which may cause yield stability analysis to be statistically challenging. In this study, we evaluated yield trial data containing 117 eastern soft red winter wheat genotypes that were grown in 35 locations in eastern production areas and four growing seasons (2012/2013 to 2015/2016). We used …
An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Larry Janssen, Bronc Mcmurtry, Matthew Stockton, Alexander Smart, Sharon A. Clay
An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Larry Janssen, Bronc Mcmurtry, Matthew Stockton, Alexander Smart, Sharon A. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Four different grazing systems: two rotational systems, a continuous grazing system, and a modified high-intensity, short-duration (mob) system were evaluated from an economic return and risk perspective. Stocking rates and average daily gains (ADG) were obtained from 2011 – 2014 from university ranch experiments in northern Nebraska. Simulation models were used to examine net returns and risk in each system and rank systems according to risk preferences. A twice through rotational grazing system was most profitable. Mob grazing was the least preferred, although when risk aversion increased, it rose in preference. Mob grazing could be profitable if adjustments increased animal …
Insect Communities In Soybeans Of Eastern South Dakota: The Effects Of Vegetation Management And Pesticides On Soybean Aphids, Bean Leaf Beetles, And Their Natural Enemies, Jonathan G. Lundgren, Louis S. Hesler, Sharon A. Clay, Scott F. Fausti
Insect Communities In Soybeans Of Eastern South Dakota: The Effects Of Vegetation Management And Pesticides On Soybean Aphids, Bean Leaf Beetles, And Their Natural Enemies, Jonathan G. Lundgren, Louis S. Hesler, Sharon A. Clay, Scott F. Fausti
Agronomy, Horticulture and Plant Science Faculty Publications
Although most pests of soybeans, Gycine max (L.), in the Northern Great Plains are managed using pesticides, farm management practices that encourage biodiversity offer promising long-term, sustainable solutions for controlling insect and weed pests profitably. The recent invasion of the Northern Great Plains by the soybean aphid (Aphis glycinesMatsumura; Hemiptera: Aphididae) has had potentially important implications for insect communities in soybeans of this region, although recent descriptions of this regional community are scarce. We describe how three pest management systems that vary in the intensity with which they rely on herbicides and insecticides (chemically intensive, reduced chemical, and …
Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman
Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman
Agronomy, Horticulture and Plant Science Faculty Publications
Numerous studies with wide-ranging results have been conducted to resolve if Great Plains soils are a C source or sink. The authors addressed the source/sink question by examining the results from producer soil samples and production surveys that were analyzed and archived by the South Dakota Soil Testing Laboratory. Results showed that between 1985 and 2010, soil organic C content increased at a rate of 326 lb C/A/year, for a total increase of 24%. The increase was attributed to planting better adapted varieties and using better management practices that on average increased corn grain yields 2.29 bu/A/year. Higher soil organic …
Nitrogen And Water Stress Impacts Hard Red Spring Wheat (Triticum Aestivum) Canopy Reflectance, Cheryl L. Reese, Daniel Long, David Clay, Sharon Clay, Dwayne Beck
Nitrogen And Water Stress Impacts Hard Red Spring Wheat (Triticum Aestivum) Canopy Reflectance, Cheryl L. Reese, Daniel Long, David Clay, Sharon Clay, Dwayne Beck
Agronomy, Horticulture and Plant Science Faculty Publications
Remote sensing has been proposed as a method for implementing an inseason spring wheat (Triticum aestivum) nitrogen (N) fertilization program. However, in fields where yields are influenced by both water and N stress, accurate N recommendations require that that the N and water stress signals be separated from each other. The objective of this study was to determine the impact of water and N stress on canopy reflectance and the ability of vegetation (NDVI, GNDVI, and BNDVI), and chlorophyll (CGreen and CRedEdge) indices to separate water and N stress. A split-plot experiment containing four blocks was conducted in 2002, 2003, …
Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus
Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus
Agronomy, Horticulture and Plant Science Faculty Publications
Common waterhemp (Amarathus rudis Sauer) is a frequent weed in glyphosate-resistant (GR) crops in the midwestern USA due, in part, to the delayed emergence of its seedlings. Variable waterhemp emergence was simulated by transplanting seedlings into both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] and bare plot areas at differing crop growth stages during two growing seasons in western Minnesota. Growth and fecundity were measured. As expected, late planted weeds produced little dry matter and few seeds, and competition from corn or soybean reduced waterhemp dry weight and fecundity by 90% compared with isolated plants. Interestingly, common …
Sorption-Desorption Of Imidacloprid And Its Metabolites In Soil And Vadose Zone Materials, Sharon V. Papiernik, William C. Koskinen, Lucia Cox, Pamela J. Rice, Sharon A. Clay, Nancy R. Werdin-Pfisterer, Kristen A. Norberg
Sorption-Desorption Of Imidacloprid And Its Metabolites In Soil And Vadose Zone Materials, Sharon V. Papiernik, William C. Koskinen, Lucia Cox, Pamela J. Rice, Sharon A. Clay, Nancy R. Werdin-Pfisterer, Kristen A. Norberg
Agronomy, Horticulture and Plant Science Faculty Publications
Sorption-desorption is one of the most important processes affecting the leaching of pesticides through soil because it controls the amount of pesticide available for transport. Subsurface soil properties can significantly affect pesticide transport and the potential for groundwater contamination. This research characterized the sorption-desorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-Nnitro-2-imidazolidinimine) and three of its metabolites, 1-[(6-chloro-3-pyridinyl)methyl]-2-imidazolidinone (imidacloprid-urea), 1-[(6-chloro-3-pyridinyl)methyl]-4,5-dihydro-1H-imidazol-2-amine (imidaclopridguanidine), and 1-[(6-chloro-3-pyridinyl)methyl]-1H-imidazol-2-amine (imidacloprid-guanidine-olefin), as a function of changing soil properties with depth in two profiles extending from the surface to a depth of 1.8 or 8 m. Sorption of each compound was highly variable and hysteretic in all cases. Normalizing the sorption coefficients (Kf) …
Precision Farming Protocols. Part 2. Comparison Of Sampling Approaches For Precision Phosphorus Management, David E. Clay, Jiyul Chang, C. Gregg Carlson, Doug Malo, Sharon A. Clay, Mike Ellsbury
Precision Farming Protocols. Part 2. Comparison Of Sampling Approaches For Precision Phosphorus Management, David E. Clay, Jiyul Chang, C. Gregg Carlson, Doug Malo, Sharon A. Clay, Mike Ellsbury
Agronomy, Horticulture and Plant Science Faculty Publications
Research is needed to compare the different techniques for developing site‐specific phosphorus (P) recommendations on a field‐wide basis. The objective of this study was to determine the impact different techniques for developing site‐specific P recommendation maps on yield and profitability. Enterprise analysis combined with a crop simulation model and detailed field characterization was used to estimate the value of spatial P information in a system where N was not limiting. The systems evaluated were continuous corn (Zea mays) and corn and soybean (Gfycine max) rotations where sampling and fertilizer applications were applied annually and semi‐annually, respectively. The sampling techniques tested …
Precision Farming Protocols: Part 1. Grid Distance And Soil Nutrient Impact On The Reproducibility Of Spatial Variability Measurements, Jiyul Chang, David E. Clay, C. Greg Carlson, Douglas D. Malo, Sharon A. Clay, John Lee, Mike Ellsbury
Precision Farming Protocols: Part 1. Grid Distance And Soil Nutrient Impact On The Reproducibility Of Spatial Variability Measurements, Jiyul Chang, David E. Clay, C. Greg Carlson, Douglas D. Malo, Sharon A. Clay, John Lee, Mike Ellsbury
Agronomy, Horticulture and Plant Science Faculty Publications
To determine temporal changes in soil nutrient status, reproducible results must be obtained at each time step. The objective of this paper was to determine the impact of grid distance on the reproducibility of spatial variability measurements. Soil samples from the 0 to 15 cm depth were collected from a 30 by 30 m grid in May 1995 in a 65 ha notill corn (Zea mays L.) field. Each bulk sample contained 15 individual cores, collected at sample points located every 11.4 cm along a transect that transversed 3 corn rows (57 cm). At each sampling point latitude, longitude, elevation, …
Weed Seed Bank Emergence Across The Corn Belt, Frank Forcella, Robert G. Wilson, Jack Dekker, Robert J. Kramer, John Cardina, Randy L. Anderson, David Alm, Karen A. Renner, R. Gordon Harvey, Sharon Clay, Douglas D. Buhler
Weed Seed Bank Emergence Across The Corn Belt, Frank Forcella, Robert G. Wilson, Jack Dekker, Robert J. Kramer, John Cardina, Randy L. Anderson, David Alm, Karen A. Renner, R. Gordon Harvey, Sharon Clay, Douglas D. Buhler
Agronomy, Horticulture and Plant Science Faculty Publications
Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of …