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Articles 1 - 14 of 14
Full-Text Articles in Physical Sciences and Mathematics
Assessing Impacts Of Winter-Hay Feeding On Soil And Forage Nutrient Dynamics In A Rotationally-Grazed Pasture System In Arkansas, Lawrence Gordon Berry Iv
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
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
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. …
Wait Until Soil Temps Drop Before Applying Anhydrous Ammonia, John E. Sawyer, Barbara Stewart, William Ehm
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
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
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
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
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.
Drought Impacts On Soil Fertility Management, John E. Sawyer
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.
Anhydrous Ammonia Application And Dry Soils, John E. Sawyer
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
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, …
Winchester Sub-Catchment Management Plan, Vivian T. Read
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).
New Opportunities For Science Students In Agronomy, Wilbur Frye
New Opportunities For Science Students In Agronomy, Wilbur Frye
Soil Science News and Views
High school students interested in science and looking for a field of study that will prepare them for a rewarding career will like the proposed new agronomy programs. The Agronomy Department at the University of Kentucky is preparing to offer undergraduate students three future-oriented options--Plant and Soil Management, Plant Science, and Soil Science. In designing these options, we tried to determine what agronomy students need to be prepared to do in a rapidly changing and highly competitive world of the 1990s.
Soybean Inoculation, J. L. Sims
Soybean Inoculation, J. L. Sims
Soil Science News and Views
Well-nodulated soybean plants are needed for most efficient soybean production. Recent research by University of Kentucky Agronomy Department personnel indicated that on Maury soil without N fertilizer, nodulating plant types of Clark 63 variety yielded 8 bushels per acre more than the non-nodulating Clark 63. With application of 125 lbs N per acre to the non-nodulating type only, both types yielded the same, showing the value of good nodulation.