Life Sciences Commons^™

Assessing Impacts Of Winter-Hay Feeding On Soil And Forage Nutrient Dynamics In A Rotationally-Grazed Pasture System In Arkansas, Lawrence Gordon Berry Iv

Graduate Theses and Dissertations

More than 38 % of United States’ rural land area was used for grazing (i.e., pastureland or rangeland) ruminant animals in 2017, constituting the largest private land use group. The expansive nature of these lands means that grazing and pasture management decisions have potential to impact water quality as well as profit margins. As a result, beef producers are under increased pressure from economic and environmental standpoints to limit application of nutrients beyond those required to grow the forage needed for animal consumption. At the same time, a large amount of nutrients is recycled back to pasture systems directly from …

Brachiaria Hybrids: Their Origin And Potential Forage Use, Esteban A. Pizarro, Michael D. Hare, John W. Miles

IGC Proceedings (1997-2023)

No abstract provided.

Evaluation Of Soybean Maturity Group And Planting Date In A Soybean-Rice Rotation On Overall Crop Productivity, Carrie Ortel

Graduate Theses and Dissertations

Little is known about the effects of soybean (Glycine max L.) management techniques on soil-nitrogen (N) credit development and its impact on the subsequent rice (Oryza sativa L.) crop’s success. This study was conducted to determine how soybean maturity group (MG) and planting date effect overall soybean productivity and its influence on the following rice crop. Various soybean planting dates (optimum and late) and MGs (3.5, 4.7, 5.4, and 5.6) were grown and followed in rotation with a rice crop. Six rates of pre-flood fertilizer-N (0, 44, 89, 134, 179, 224 kg N ha-1) were applied to the rice crop. …

Winter Grazing Management, Stephen K. Barnhart, James R. Russell, Douglas L. Karlen, Michael J. Tidman

Douglas L Karlen

Why winter grazing? Beef cow herd and sheep flock records show that winter feeding costs are livestock producers' single largest production expense. Managing through winter weather while keeping feeding costs low is an essential part of maintaining a profitable operation. Iowa's climate generally allows forage growth only during a 7-to-8 month period. Extending the grazing of this forage--even an extra 3 or 4 weeks in late autumn and winter--is an economical way to maintain or increase livestock profitability. Some producers extend the grazing season by using stockpiled forage, whereas others use crop residue, and many combine the use of stockpiled …

Wait Until Soil Temps Drop Before Applying Anhydrous Ammonia, John E. Sawyer, Barbara Stewart, William Ehm

John E. Sawyer

With the early harvest, Iowa’s conservation leaders are encouraging farmers to wait until soil temperatures lower before applying anhydrous ammonia (NH3) this fall. Anhydrous ammonia applied before daily soil temperatures remain below 50 degrees Fahrenheit and continue trending lower can result in the nitrogen loss that can impact crop development and have negative environmental impacts, such as enhanced leaching into groundwater and streams once converted to nitrate.

Wet Conditions And Change In Soil Profile Nitrate, John E. Sawyer

John E. Sawyer

I wrote an ICM News article February 21, 2013, that provided a summary of fall soil profile nitrate sampling results following the 2012 corn harvest. As I cautioned in that and other articles, the amount of nitrate-N that might remain for a 2013 corn crop depends on springtime rainfall. Unfortunately, much of Iowa has received considerable precipitation since soils thawed, especially the eastern two-thirds of Iowa. The two maps of the Midwest region show the total precipitation and deviation from normal since March 7, 2013. Tile lines are flowing again, and nitrate in the profile will move with percolating water. …

Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams

Graduate Theses and Dissertations

Continued achievement of soybean [Glycine max (L.) Merr.] yields greater than 6719 kg ha-1 (100 bu ac-1) will depend on decreasing the yield gap, which is contingent on gathering more information regarding the soil physical, chemical, and microbiological environment and the main plant factors contributing to high-yield soybean. Therefore, understanding the main factor differences between high- and average-yield areas may provide insight for making management decisions to increase yields. The objectives of this study were i) to evaluate the effects of region and soil depth on soil property differences between high- and average-soybean-yielding areas, ii) to determine which soil properties …

The Illinois Soil Nitrogen Test: Should It Be Used In Iowa?, John E. Sawyer, Mohammod Ali Tabatabai

John E. Sawyer

The test was developed several years ago at the University of Illinois by researchers in the Department of Natural Resources and Environmental Sciences. It is a laboratory procedure designed to measure N liberated from soil heated for 5 hours with dilute alkali solution (sodium hydroxide). The test does not measure nitrate, but does measure exchangeable ammonium and a fraction of soil organic N.

Interpreting P And K Soil Test Results, John E. Sawyer, Antonio P. Mallarino

John E. Sawyer

Soil testing is a key component for determining the need for phosphorus (P) and potassium (K) fertilization. Also, if fertilization is required, test results guide the rate of application recommended to optimize production. Through extensive field research, specific soil tests are calibrated against the expectation of response to applied P and K; that is, they provide both a relative index of the availability of P and K to the crop being grown and an indication of the magnitude of yield increase one might expect when nutrients are applied, thus providing the interpretation of text results.

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).

Drought Impacts On Soil Fertility Management, John E. Sawyer

John E. Sawyer

If crop production was severely reduced because of dry conditions this year, there are a few items you can consider when planning for next year's crop. One, with severely damaged crops and low yields you might credit some of the phosphorus (P) and potassium (K) applied for this year's crop to next year, as much less removal will occur in grain harvest of the lower than expected yield.

Corn Stalk Nitrate Interpretation, John E. Sawyer

John E. Sawyer

You’ve gotten results from corn stalk nitrate samples collected this fall. (Corn stalk nitrate analysis form.) Now, what do the results mean? The stalk nitrate test is based on the concentration of nitrate-N in the lower corn stalk (8 inch segment from 6 to 14 inches above the ground) when the plant reaches maturity (See Cornstalk testing to evaluate nitrogen management, PM 1584). In general, a larger amount of plant-available N in the soil during the time period before plant maturity results in a greater concentration of nitrate in the lower stalk. However, the stalk nitrate-N concentration …

Corn Stalk Nitrate Interpretation, John E. Sawyer

John E. Sawyer

You’ve gotten results from corn stalk nitrate samples collected this fall. (Corn stalk nitrate analysis form.) Now, what do the results mean? The stalk nitrate test is based on the concentration of nitrate-N in the lower corn stalk (8 inch segment from 6 to 14 inches above the ground) when the plant reaches maturity (See Cornstalk testing to evaluate nitrogen management, PM 1584). In general, a larger amount of plant-available N in the soil during the time period before plant maturity results in a greater concentration of nitrate in the lower stalk. However, the stalk nitrate-N concentration can be greatly …

Anhydrous Ammonia Application And Dry Soils, John E. Sawyer

John E. Sawyer

It is almost time that anhydrous ammonia (NH3) applications could begin (remember 50 F and cooling 4-inch soil temperature). However, many soils in Iowa are quite dry this fall. So, can anhydrous ammonia be applied to dry soil? Will it be held in dry soil?

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, …

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

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.

Crop Updates 2008 - Cereals, Christine Zaicou, Shahajahan Miyan, Brenda Shackley, Steve Penny, Sarah Ellis, Darshan Sharma, Blakely Paynter, Jeff Russell, Andrea Hills, Glen Riethmuller, Bill Bowden, Paul Blackwell, Harmohinder Dhammu, Vince Lambert, Chris Roberts, David Cox, Sally Cox, Jeremy Lemon, Paul Damon, Zed Rengel, Geoff Thomas, Ciara Beard, Anne Smith, Kith Jayasena, Sean Kelly, Rob Loughman, Bill Macleod, Raj Malik, Ravjit Khangura, Vivien Vanstone, Colin Hanbury, Mehreteab Aberra, Gordon Masnish, Brenda Coutts, Geoff Strickland, Monica Kehoe, Dustin Severtson, Roger Jones, Dominie Wright, Megan Jordan, Xinhua He, Eli Manyol, Song-Ai Nio, Imran Malik, Tina Botwright-Acuña, Len Wade, Nigel Metz, Linda Price, Dean Diepeveen, Leisa Armstrong, Peter Clarke, Doug Abrecht, Rudi Appels, Matthew Bellgard

Crop Updates

This session covers twenty four papers from different authors:

WHEAT AGRONOMY

1. Wheat variety performance in the Northern Agricultural Region in 2007, Christine Zaicou, Department of Agriculture and Food

2. Wheat variety performance on the Central Agricultural Region in 2007, Shahajahan Miyan, Department of Agriculture and Food

3. Response of wheat varieties to sowing time in the Great Southern and Lakes Region in 2007, Brenda Shackley and Steve Penny, Department of Agriculture and Food

4. Wheat variety performance in the South Coastal Region in 2007, Sarah Ellis, Department of Agriculture and Food

5. Flowering dates of wheat varieties in Western …

Wheat Variety Guide 2008 Western Australia, Christine Zaicou, Ben Curtis, Harmohinder Dhammu, Sarah Ellis, Dorthe Jorgensen, Shahajahan Miyan, Steve Penny, Brenda Shackley, Darshan Sharma

Bulletins 4000 -

This guide summarises performance characteristics of commercially available wheats and some pre-commercial lines. These lines have undergone testing in the National Variety Testing Project (NVT), Department of Agriculture and Food, Western Australia (DAFWA) wide-scale crop variety testing (CVT) and/or variety specific agronomy projects. This information includes variety summaries (Table 1), agronomic, disease and herbicide tolerance characteristics (Tables 2 to 4), medium- to long-term yield performance by wheat grade and Agzone (Tables 5 and 6). A review of regional performance in 2007 is followed by a comprehensive summary of 2007 variety time of sowing experiments (Tables 7 to 14) and flowering …

Crop Updates 2004 - Cereals, Wal Anderson, Vivian Vanstone, Robert Loughman, Vanessa Stewart, Darshan Sharma, Christine Zaicou-Kunesch, Brenda Shackley, Mohammad Amjad, Steve Penny Jr, Glen Riethmuller, Jeromy Lemon, Mario D'Antuono, Veronika Reck, Ben Curtis, Judith Devenish, Melaine Kupsch, Anne Smith, Blakely Paynter, Roslyn Jetter, Leanne Schulz, Jocelyn Ball, Tom Sweeny, Stephen Loss, Ashleigh Brooks, Justin Fuery, Geoff Anderson, Zed Rengel, Paul Damon, Eddy Pol, Narelle Hill, Ray Tugwell, Ron Mctaggart, Nathan Moyes, John Majewski, Manisha Shanker, James Piotrowski, Ciara Beard, Kithsiri Jayasena, Kazue Tanaka, Grey Poulish, Debbie Thackray, Rohan Prince, Roger Jones, Peter Nelson, Nigel Metz, Leisa Armstrong, Yee Leong (Alex) Yung, Moin Salam, David Tennant

Crop Updates

This session covers twenty eight papers from different authors:

PLENARY

1. Declining profitability in continuous cropping systems. Is more wheat the answer on Duplex soil? Dr Wal Anderson, Department of Agriculture

2. Disease implications of extending the wheat phase in low-medium rainfall areas, Dr Vivian Vanstone and Dr Robert Loughman, Department of Agriculture

3. Prolonged wheat phase on duplex soils – where do weeds set the boundary? Vanessa Stewart, Department of Agriculture

WHEAT AGRONOMY

4. Management of small grain screenings in wheat, Dr Wal Anderson and Dr Darshan Sharma, Department of Agriculture

5. Agronomic responses of new wheat varieties, Christine …

Winchester Sub-Catchment Management Plan, Vivian T. Read

Soil conservation survey collection

The 590 Ha Winchester sub-catchment has no apparent external drainage. Groundwater levels are rising causing site specific problems. Wind erosion has severely affected some areas.The objective of this report is to provide a sub-catchment management plan that is based on sustainable agricultural systems and a hydrological equilibrium. The recommendations aim to meet this objective in the long term. Recommendations to achieve short term results are considered separately. These measures have relatively high installation and maintenance costs. They should be considered as interim management methods until the recommendations for long-term control become effective (perhaps 3 - 5 years after implementation).