Charles Shapiro
University of Nebraska Lincoln, Agronomy and Horticulture, Faculty Member
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Research Interests: Engineering, Environmental Engineering, Agricultural Engineering, Environmental Science, Soil Science, and 15 moreFood Science, Forestry, Biomedical Engineering, Irrigation, Productivity, Irrigation Management, Water use efficiency, Soil moisture, Maize, Evapotranspiration, Civil and Environmental Engineering, Water Productivity, Water Content, Agricultural and Bioresource Engineering, and Agronomy and Crop Science
Duration of cover crop (CC) management, CC biomass production, and other factors could impact how CC affects soil health. We studied the 8‐year cumulative impacts of winter rye (Secale cereale L.) CC on soil physical, chemical, and... more
Duration of cover crop (CC) management, CC biomass production, and other factors could impact how CC affects soil health. We studied the 8‐year cumulative impacts of winter rye (Secale cereale L.) CC on soil physical, chemical, and biological properties in rainfed and irrigated no‐till corn (Zea mays L.)‐based systems in the western US Corn Belt. Average annual CC biomass production was 0.56 ± 0.51 Mg ha−1 at the rainfed site and 0.98 ± 0.95 Mg ha−1 at the irrigated site. After 8 years, CC improved particulate organic matter (POM) and mean weight diameter of water‐stable aggregates (MWD) compared with no CC in the 0–5 cm soil depth at both sites. Cover crop increased total POM concentration by 2.8 mg g−1 at the rainfed site and by 13.4 mg g−1 at the irrigated site, while it increased MWD by 0.39 mm at the rainfed site and by 0.79 mm at the irrigated site. Also, CC increased soil C at a rate of 0.125 Mg ha−1 year−1 in the 0–5 cm depth but only at the rainfed site. Cover crop affected neither water infiltration nor available water but improved microbial biomass. Changes in other properties were site‐dependent. Cover crop improved many soil properties after 8 years even though measurement taken after 4 years showed no significant effect of CC, which indicates CC slowly impacts properties in this environment. Low CC biomass production and high biomass input from corn‐based systems may explain the slow soil response. In general, winter rye CC enhances near‐surface soil properties in the long term.
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Cover crop growing periods in the western U.S. Corn Belt could be extended by planting earlier. We evaluated both pre‐harvest broadcast interseeding and post‐harvest drilling of the following cover crops: (a) cereal rye (Secale cereale... more
Cover crop growing periods in the western U.S. Corn Belt could be extended by planting earlier. We evaluated both pre‐harvest broadcast interseeding and post‐harvest drilling of the following cover crops: (a) cereal rye (Secale cereale L.) [RYE]; (b) a mix of rye + legumes + brassicas [MIX1], (c) a mix of rye + oat [Avena sativa L.] + legumes + brassicas (MIX2), (d) legumes [LEGU]) and (e) a no cover crop control. These were tested in continuous corn (Zea mays L.) [corn–corn] and soybean [Glycine max (L.) Merr.]–corn systems [soybean–corn] at three sites in Nebraska for their effect on cover crop productivity, soil nutrients, and subsequent corn performance. At the sites with wet fall weather, pre‐harvest broadcasting increased cover crop biomass by 90%, to 1.29 Mg ha−1 for RYE and 0.87 Mg ha−1 for MIX1 in soybean–corn, and to 0.56 Mg ha−1 and 0.39 Mg ha−1 in corn–corn, respectively. At the drier site, post‐harvest drilling increased biomass of RYE and MIX1 by 95% to 0.80 Mg ha−1 in...
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too wet to maintain air spaces within the composting pile, and to reduce water content and/or to change the C:N ratio. Dry and fibrous materials, such as sawdust, leaves, finely chopped straw, or peat moss, are good bulking agents for... more
too wet to maintain air spaces within the composting pile, and to reduce water content and/or to change the C:N ratio. Dry and fibrous materials, such as sawdust, leaves, finely chopped straw, or peat moss, are good bulking agents for composting wet manure or organic residues. Temperature is the most common indicator of how composting is progressing. Elevated temperature is necessary to destroy pathogens and weed seeds in manure or other organic materials. Environmental Protection Agency (EPA) regulations for composting municipal waste require that the temperature be maintained at 131oF or above for at least three days to destroy pathogens. A temperature of 145oF within the compost pile is needed to destroy weed seeds. Depending on the ambient temperature, a complete composting process may take two to six months. The water content of mature compost should be less than 50 percent and preferably in the range of 30 to 35 percent. The C:N ratio should be less than 20.
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Extension Circular 02-721 discusses Nebraska\u27s CNMP odor management plan workbook
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Extension Circular 02-722: This circular is to assist Nebraska livestock producers in developing and using their Comprehensive Nutrient Management Plan. It talks about instructions for inventory of resources, developing strategic plans... more
Extension Circular 02-722: This circular is to assist Nebraska livestock producers in developing and using their Comprehensive Nutrient Management Plan. It talks about instructions for inventory of resources, developing strategic plans and annual plans, and instructions/forms for multiple records
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Manure testing: what to request? Manure testing is necessary to make optimum use of manure while protecting water resources. The Manure Sample Submission Form requests information required for reliable interpretation of the results
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This NebGuide addresses issues of micronutrient fertilizer use with a focus on zinc and iron. Of the 17 elements known to be essential for plant growth, eight are used in very small amounts and, with the exception of iron, have an uptake... more
This NebGuide addresses issues of micronutrient fertilizer use with a focus on zinc and iron. Of the 17 elements known to be essential for plant growth, eight are used in very small amounts and, with the exception of iron, have an uptake of less than 1 pound per acre per year (Table 1). These elements are classified as micronutrients and include zinc (Zn), iron (Fe), manganese (Mn), copper (Cu), boron (B), molybdenum (Mo), chlorine (Cl), and nickel (Ni). Interest in micronutrients has increased because of accelerated rates of nutrient removal due to greater yields and the availability of alternative micronutrient products.
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In the past, fungicide applications on hybrid corn were generally regarded as uneconomical. Recently, the higher price of corn combined with increased corn-following-corn planting practices and associated increased disease risk, have made... more
In the past, fungicide applications on hybrid corn were generally regarded as uneconomical. Recently, the higher price of corn combined with increased corn-following-corn planting practices and associated increased disease risk, have made fungicide applications on corn more common. However, there is currently a lack of data regarding the occurrence of fungicides in streams, especially in areas where it is applied primarily to corn. As the use of fungicides in corn-producing areas continues to increase, baseline data on the presence of fungicides in streams will be important for documenting changes in the occurrence of these compounds, and potential aquatic and human-health effects of the fungicides in the environment. The U.S. Geological Survey completed a study between May and September 2008 to determine the occurrence of fungicides in surface-water samples from six streams in corn-producing watersheds in Nebraska. The samples collected during this study were analyzed for the fungi...
Research Interests: Environmental Science, Kinetics, Best practice, North Carolina, Project Planning, and 15 moreDrinking Water, Agricultural Production, Historical Data, Human health, Integrated Approach, Decision making process, Management Practice, Best management practice, Economic Benefit, Rainfall Simulation, Operation and Maintenance, Data Gathering, Cryptosporidium parvum, onsite wastewater treatment systems, and Bare Soil
Winter wheat-ecofallow-corn rotations are common in the central and high plains. Drought has severely decreased corn yields. Preliminary research with skip row configurations suggested that they may conserve moisture for later use during... more
Winter wheat-ecofallow-corn rotations are common in the central and high plains. Drought has severely decreased corn yields. Preliminary research with skip row configurations suggested that they may conserve moisture for later use during dry years and stabilize corn yields. ...
The USDA-CSREES Managed Ecosystems and Nebraska Corn Board is funding a project to reduce P loading of surface waters associated with crop-ethanol-livestock ecosystems. It has five main objectives: 1) removal of P from the corn-ethanol... more
The USDA-CSREES Managed Ecosystems and Nebraska Corn Board is funding a project to reduce P loading of surface waters associated with crop-ethanol-livestock ecosystems. It has five main objectives: 1) removal of P from the corn-ethanol stream to reduce dietary P for beef cattle; 2) develop a decision tool for feedlot manure handling options; 3) determine the effects of land application practices on manure P loss to surface waters; and 4) educate corn producers of P management issues. About 77 and 90% of the phytate P in beer bottom from dry-milling and in light steep water from wet milling was effectively degraded to phosphoric acid; experiments are underway for the removal of the degraded phytate P from the ethanol stream. Composting of feedlot manure was not found to be cost-effective relative to stockpiling for most feedlot situations unless the compost is a value-added product or if initial manure water content is >60%. The manure handing decision tool is under development. O...
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Summary Nitrogen (N) is the most important nutrient for plant growth and production. Nitrogen uptake efficiency is dependent on a number of factors. Water management influences the transformation of N sources applied to the soil and... more
Summary Nitrogen (N) is the most important nutrient for plant growth and production. Nitrogen uptake efficiency is dependent on a number of factors. Water management influences the transformation of N sources applied to the soil and transport of the nitrate form of N in the soil. Nitrate-N is the final product of N transformations and is quite mobile in soils with the water front. Leaching of nitrate below the rootzone is an economic loss and contributes to non-point source pollution of groundwater. In this chapter we summarize the ...
Research Interests: Environmental Science, Irrigation Management, Water Management, Ground Water, Plant growth, and 13 moreCrop Production, Nitrogen, Nitrogen Uptake, Drinking Water Quality, Crop Improvement, Biological Process, Economic Loss, Best management practice, Production System, Precision Farming, Agriculture Production, Cover Crop, and N uptake
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The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers (ASABE), and... more
The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers (ASABE), and its printing and distribution does not constitute an endorsement of views which may be expressed. Technical presentations are not subject to the formal peer review process by ASABE editorial committees; therefore, they are not to be presented as refereed publications. Citation of this work should state that it is
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Abstract Mechanical cover crop (CC) termination can reduce tillage in organic rotations, but research is needed to develop recommendations for producers in the upper Midwest, U.S.A. Field studies were conducted near Concord, NE, U.S.A.,... more
Abstract Mechanical cover crop (CC) termination can reduce tillage in organic rotations, but research is needed to develop recommendations for producers in the upper Midwest, U.S.A. Field studies were conducted near Concord, NE, U.S.A., in 2008–2009 and 2009–2010. This study compared no-till [roller/crimper (CRIMP) and broadcast propane flame (FLAME)] and spring disk (DISK) termination of legume, grass, and broadleaf CCs and their effects on a subsequent maize or soybean crop. Before sowing the grain, overwintering CC species were terminated; frost-killed (FROST) CCs were also disked in the spring. Weeds were controlled via cultivation in the tilled systems (DISK and FROST); CC residue was left as a surface mulch in the no-till systems (CRIMP and FLAME). Termination method/tillage regime had greater influence than CC species on grain yield and quality, with tilled treatments performing better than CRIMP and FLAME, likely due to early season weed pressure and low stand establishment in the no-till treatments. Maize yield for the DISK system was on average 6.8 Mg ha−1 in both trials, while FLAME and CRIMP produced 57–78% less. Soybean yields for DISK were 3.3 and 2.0 Mg ha−1; CRIMP and FLAME produced 21–33% less in 2009 and 56% less in 2010. The CCs best suited to no-till systems were winter rye (superior biomass) and hairy vetch (successful mechanical termination). FLAME performed as well as CRIMP. The results suggested that no-till CC termination should be employed within a comprehensive weed management system to minimise yield losses due to weeds and CC regrowth.
Green manure crops must produce high biomass to supply biological N, increase organic matter and control weeds. The objectives of our study were to assess above-ground biomass productivity and weed suppression of clover (Trifolium spp.)... more
Green manure crops must produce high biomass to supply biological N, increase organic matter and control weeds. The objectives of our study were to assess above-ground biomass productivity and weed suppression of clover (Trifolium spp.) green manures in an organic soybean [Glycine max (L.) Merr.]-winter wheat (Triticum aestivum L.)-corn (Zea mays L.) rotation in eastern Nebraska in three cycles (2011–12, 2012–13, 2013–14). Treatments were green manure species [red clover (T. pratense L.) and white clover (T. repens L.)] undersown into winter wheat in March and green manure mowing regime (one late summer mowing or no mowing). We measured wheat productivity and grain protein at wheat harvest, and clover and weed above-ground biomass as dry matter (DM) at wheat harvest, 35 days after wheat harvest, in October and in April before clover termination. Winter wheat grain yields and grain protein were not affected by undersown clovers. DM was higher for red than for white clover at most sam...
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Crop performance in rainfed cropping systems generally is dependent on rainfall amount and distribution. The objective of this study was to analyze the long-term consequences of rainfall expressed as a standardized precipitation index... more
Crop performance in rainfed cropping systems generally is dependent on rainfall amount and distribution. The objective of this study was to analyze the long-term consequences of rainfall expressed as a standardized precipitation index (SPI) and fertilizer nitrogen (N) on yields and risk probabilities of maize in the udic-ustic moisture regimes in the Great Plains in Nebraska. The SPI is a precipitation index for classifying drought stress conditions. The study was conducted on a Kennebec silt loam (Cumulic Hapludoll) over an 11-year period, 1986-1996, using monoculture maize (Zea mays L.) and maize in rotation with soybean (Glycine max.(L.) Merr.) in combination with N fertilizer levels between 0 and 160 kg ha −1 . Maize yields in monoculture ranged from 4.8 to 5.7 Mg ha −1 , and from 6.4 to 6.8 Mg ha −1 in rotation. The differences in yields between monoculture and rotation were larger at low N rates and decreased as N fertilizer increased above 40 kg ha −1 . Current year's ma...
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Text: Surface application of manure may increase the risk of phosphorus loss in runoff. Manure application, however, often results in increased soil aggregate stability with reduced runoff and erosion and, therefore, reduced P transport... more
Text: Surface application of manure may increase the risk of phosphorus loss in runoff. Manure application, however, often results in increased soil aggregate stability with reduced runoff and erosion and, therefore, reduced P transport potential. Three field studies were conducted with silt loam or silty clay loam soil in Nebraska to determine how water-stable soil aggregation in the 0- to 25-mm soil depth is affected: 1) by application of raw or composted feedlot manure; 2) by repeated annual manure application; and 3) by the residual effect of composted manure applied five to seven years before sampling. Large macro- aggregates (>2 mm) were increased 200% or more by both manure and compost application within 15 days after application; the effect persisted for the seven months of study with a greater effect due to compost application. Aggregate stability was similar for incorporation and no incorporation of the applied compost or manure. Bray-P1 in large macro-aggregates was 20...
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Research Interests: Management, Environmental Science, Agriculture, Phosphorus, Nutrients, and 4 moreToxic, soil pH, Soil Acidity, and Acid
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Research Interests: Engineering and Chemistry
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When managed correctly, nutrients in livestock manure can be a valuable resource. When managed improperly, however, these same nutrients represent a potential environmental pollutant. Accurate crediting of manure nutrients within a total... more
When managed correctly, nutrients in livestock manure can be a valuable resource. When managed improperly, however, these same nutrients represent a potential environmental pollutant. Accurate crediting of manure nutrients within a total crop nutrient program is fundamental to utilizing manure as a resource. This NebGuide illustrates how to estimate the crop available manure nutrients (part c, Figure 1) and calculate an agronomically based manure application rate. To illustrate this process, example calculations are provided and a worksheet is included allowing you to complete the calculations as well. To accurately credit crop available manure nutrients, a producer needs three pieces of information: 1. Manure nutrient of concentration at time of land application — the concentration of individual nutrients in manure measured as pounds of nutrient per unit of manure (ton, 1,000 gallons or acre-inch). 2. Manure application rate — the rate at which manure is applied to the land measure...