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Full-Text Articles in Plant Sciences

45th Annual North Central Extension-Industry Soil Fertility Conference, John E. Sawyer Jul 2016

45th Annual North Central Extension-Industry Soil Fertility Conference, John E. Sawyer

John E. Sawyer

If you would like to learn more about current soil fertility issues and research being conducted at universities across the North Central region, then consider attending the 45th Annual North Central Extension-Industry Soil Fertility Conference on November 4-5, 2015, from 1 p.m. to noon, at the Holiday Inn Airport in Des Moines, Iowa. The conference will include invited presentations from university and industry leaders, research reports from university soil fertility researchers, and posters outlining research by graduate students at universities across the North Central region (Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Nebraska, North Dakota, Ohio, Ontario, Pennsylvania, South Dakota, …


Application Checkpoints For Fall Ammonia, H. Mark Hanna, John E. Sawyer Jul 2016

Application Checkpoints For Fall Ammonia, H. Mark Hanna, John E. Sawyer

John E. Sawyer

Depending on postharvest field conditions, some producers will soon be considering anhydrous ammonia application. Using fall labor to apply fertilizer can be attractive but needs to be balanced with the potential for nutrient loss. To avoid conversion of anhydrous ammonia from ammonium to more leachable forms of nitrogen, application should be delayed until average soil temperature is below 50°F and trending lower. Measure the 4-inch soil temperature at near 10 a.m. or 7 p.m. or check Iowa State University's county soil temperatures and forecast.


Apply Nitrogen Or Plant Corn?, John E. Sawyer Jul 2016

Apply Nitrogen Or Plant Corn?, John E. Sawyer

John E. Sawyer

The end of the optimal time for corn planting is quickly approaching. Getting corn planted should be a priority over making nitrogen (N) fertilizer applications. However, along with that decision there should be a plan to get N applications completed after planting and crop emergence. Switching products and application from preplant to sidedress requires availability of needed fertilizers and equipment. So have a plan in place.


Sulfur Management For Iowa Crop Production, John E. Sawyer, Brian J. Lang, Daniel W. Barker Jul 2016

Sulfur Management For Iowa Crop Production, John E. Sawyer, Brian J. Lang, Daniel W. Barker

John E. Sawyer

Summary of statewide evaluation in Iowa of alfalfa and corn yield response to applied sulfur fertilizers. On-farm, small-plot and field-length strip trial yield response data presented from 2005-2013.


Sensing Nitrogen Stress In Corn, John E. Sawyer Jul 2016

Sensing Nitrogen Stress In Corn, John E. Sawyer

John E. Sawyer

Water quality concerns and high N fertilizer prices have made more precise nitrogen management strategies important to improve efficiency and profitability. Get the details here.


Interpretation Of Soil Test Results, Antonio P. Mallarino, John E. Sawyer Jul 2016

Interpretation Of Soil Test Results, Antonio P. Mallarino, John E. Sawyer

John E. Sawyer

A detailed explanation on how to interpret soil test results to assist with soil nutrient recommendations.


Nitrogen Use In Iowa Corn Production, John E. Sawyer Jul 2016

Nitrogen Use In Iowa Corn Production, John E. Sawyer

John E. Sawyer

Nitrogen is essential for growth and reproduction of crops and is involved in many important plant biochemical processes. Nitrogen management is critical for optimal yields for corn production systems. This publication discusses long-term research done in Iowa and shows corn yields average about 60 bu/acre for continuous corn and 115 bu/acre for corn following soybean when corn is not fertilized. However, corn fertilized with N will easily yield 200 bu/acre or more. This means soil management and nitrogen fertilization practices, such as using economical optimum N rates, should be used to help optimize crop yields, use N efficiently, and enhance …


A General Guide For Crop Nutrient And Limestone Recommendations In Iowa, Antonio P. Mallarino, John E. Sawyer, Stephen K. Barnhart Jul 2016

A General Guide For Crop Nutrient And Limestone Recommendations In Iowa, Antonio P. Mallarino, John E. Sawyer, Stephen K. Barnhart

John E. Sawyer

Find phosphorus and potassium recommendations, micronutrient recommendations, and limestone recommendations for soils.

Also find soil test procedures and categories.


Fertilizing Pasture, Stephen K. Barnhart, Antonio P. Mallarino, John E. Sawyer Jul 2016

Fertilizing Pasture, Stephen K. Barnhart, Antonio P. Mallarino, John E. Sawyer

John E. Sawyer

Research has demonstrated large increases in days of grazing, annual gain, or milk production per acre by fertilizing low yielding pastures. This publication addresses grass pasture fertilization rates, timing, and soil quality, including: types of nitrogen; nitrogen rates, response, and profits; and phosphorous and potassium (P-K) rates for legume-grass pastures.


Nutrient Considerations With Corn Stover Harvest, John E. Sawyer, Antonio P. Mallarino Jul 2016

Nutrient Considerations With Corn Stover Harvest, John E. Sawyer, Antonio P. Mallarino

John E. Sawyer

Weigh the relationships between corn stover harvest (as compared to grain only harvest) with the research presented in this publication.Make informed decisions about using stover harvest for bioenergy and using corn residue for soil sustainability. Find corn N, P, and K fertilization recommendations needed to maintain desirable soil-test values.


Impact Of Swine Manure Applications On Nitrate And Phosphorus In Subsurface Drainage Water, Rameshwar S. Kanwar, James L. Baker, Carl H. Pederson, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky Jul 2016

Impact Of Swine Manure Applications On Nitrate And Phosphorus In Subsurface Drainage Water, Rameshwar S. Kanwar, James L. Baker, Carl H. Pederson, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky

John E. Sawyer

Nonpoint source nutrient pollution related to land application of manures is recognized as an important environmental and social issue for several reasons. First, manure from swine production facilities can have serious impacts on the quality of ground water resources. Second, several states are in the process of creating laws and/or regulations to reduce nitrogen (N) and phosphorus (P) loadings from manure to soil and water resources. Third, pollution of water resources from nutrients supplied by manure to croplands will help set parameters for developing public policies on the management of manure.


Impact Of Swine Manure Application On Water Quality, Rameshwar S. Kanwar, Carl H. Pederson, Matthew J. Helmers, John E. Sawyer, Antonio P. Mallarino Jul 2016

Impact Of Swine Manure Application On Water Quality, Rameshwar S. Kanwar, Carl H. Pederson, Matthew J. Helmers, John E. Sawyer, Antonio P. Mallarino

John E. Sawyer

Nonpoint source nutrient pollution related to land application of manures is recognized as an important environmental and social issue for several reasons. First,swine manure application to land can impact water quality. Second, several states are in the process of creating laws and/or regulations to reduce nitrogen and phosphorus loadings from manure to soil and water resources. Third, the quality of water resources will help set parameters for developing public policies on management of manure.


Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri Jul 2016

Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri

John E. Sawyer

Iowa research has demonstrated that cover crops can improve soil productivity and water quality by increasing soil organic matter and reducing nitrate nitrogen (N) leaching. Other research has investigated and is investigating the agronomic and economic viability of using cereal rye cover crops in continuous corn or corn-soybean rotations. However, no Iowa research has evaluated under natural rainfall the impact of cover crops on phosphorus (P) and N loss with surface runoff interacting with other management practices. The need for this type of research was indicated in the Iowa Nutrient Reduction Strategy documents. This effort assessed what would be needed …


Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers Jul 2016

Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers

John E. Sawyer

Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.


Isu Extension And Outreach Offers Soil Fertility Short Course, John E. Sawyer, Brent A. Pringnitz Jul 2016

Isu Extension And Outreach Offers Soil Fertility Short Course, John E. Sawyer, Brent A. Pringnitz

John E. Sawyer

Making sound soil fertility management decisions is an important part of successful crop production, on both an economic and environmental level. Iowa State University Extension and Outreach will offer a two-day short course focusing on principles of soils, soil fertility and nutrient management to help crop production professionals make better decisions. Highlights include sampling and testing; pH and liming; essential, secondary and micronutrients; nitrogen dynamics; manure management; and more. The small class size allows for increased discussion and interaction with Extension and Outreach specialists.


Corn Response To Sulfur On Illinois Soils, R. G. Hoeft, J. E. Sawyer, R. M. Vanden Heuvel, M. A. Schmitt, G. S. Brinkman Dec 1984

Corn Response To Sulfur On Illinois Soils, R. G. Hoeft, J. E. Sawyer, R. M. Vanden Heuvel, M. A. Schmitt, G. S. Brinkman

John E. Sawyer


Field studies were conducted over a three-year period at a total of 82 site-years to evaluate the sulfur (S) status of representative Illinois soils. In addition, greenhouse studies were conducted using soils from two of the three years of field experiments. The sites selected were either low in organic matter, sandy in texture and/or in areas 
where apparent S deficiency had been reported. At each location, gypsum was applied at a rate to supply 50 lb S/ac prior to the final tillage operation before planting. Whole plant samples were collected at the sixth-leaf stage of growth and ear leaf samples were …