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2008
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Authors
Abunyewa, A
Ahuja, L
Allen, B
Archer, D
Archibequet, S
Ashley, R
Bartolo, M
Bauder, T
Bean, B
Benajmin, J
Benjamin, J
Berrada, A
Borch, T
Bradbury, G
Brandt, S
Brobst, R
Bronson, K
Brummer, J
Bullock, P
Calderon, F
Calderón, F
Carr, P
Claassen, M
Coffin, K
Davis, J
Del Grosso, S
Doesken, K
Elliott, A
Endres, G
Engle, T
Eriksmoen, E
Evans, B
Ferguson, R
Fixen, P
Flore, N
Franzen, D
Gelderman, R
Godsey, C
Goos, J
Gordon, B
Gordon, W
Griffith, D
Haby, V
Halvorson, A
Hansen, N
Harapiak, J
Hatfield, J
Heer, W
Henry, B
Hergert, G
Holman, J
Holzapfel, C
Hughes, H
Irvine, R
Iversen, B
Jabro, J
Jackson, G
James, D
Janssen, K
Jifon, J
Johnson, B
Jones, C
Karamanos, R
Kennedy, W
Khosla, R
Kim, J
Klein, B
Lafond, G
Leikam, K
Leonard, A
Lester, G
Loecker, J
Lukach, J
Lyon, D
Maddox, L
Malapati, A
Marcillac, N
Martin, G
Martin, K
Martin, V
Mason, S
Massey, M
May, W
McKay, K
Mengel, D
Mikha, M
Miller, R
Morrison, M
Moshia, M
Mosier, A
Nelson, J
Nelson, N
Nielsen, D
Nielsen, R
Olson, B
Pearson, R
Peterson, G
Poss, D
Quarles, D
Reich, R
Reule, C
Riveland, N
Roberts, D
Sainju, U
Schepers, J
Schlegel, A
Schwartz, R
Shanahan, J
Shanklin, L
Sheffield, R
Sherrod, L
Stevens, B
Stewart, W
Stonaker, F
Stromberger, M
Thompson, C
Tucker, D
Valliant, J
Van Wychen, S
Vigil, M
Westfall, D
Wienhold, B
Wilhelm, W
Wortmann, C
Topics
Type
Oral
Poster
Year
2008
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Year

Filter results44 paper(s) found.

1. A Comparison of Dryland Grasspea (Lathyrus sativus L.) and Admiral Pea (Pisum sativum L.) Grown Under Different Row Spacings

Grasspea (GP) is a drought-tolerant legume grown for forage and grain in Europe and the Middle East.  It has potential value to be used as a nitrogen-fixing crop in rotation with common grain crops in the High Plains. However, the agronomics of GP for our region have not been investigated to date. We carried out a field experiment to compare the growth of GP and Admiral Pea (AP) in 76 cm rows vs. 19 cm rows. The growth, yield, grain N content, phenology, and water utilization was me... F. Calderon, M. Vigil, D. Nielsen, J. Benjamin, M. Mikha

2. A Historical Yield Performance in Western Kansas

A primary objective in Agronomy is to increase crop yields through improved varieties/hybrids and production practices. Crop variety/hybrid performance tests of irrigated corn, irrigated wheat, dryland wheat, irrigated grain sorghum, dryland grain sorghum, and irrigated soybeans were conducted at the Southwest Research Extension center in Garden City, Kansas annually over the last 50 years. For each crop, the varieties/hybrids yields were averaged for each year from 1956 through 2006. These t... J. Holman, C. Thompson, A. Schlegel

3. A Use of Skip-row Planting As a Strategy for Drought Mitigation in the West Central Great Plains

Skip-row planting of corn and sorghum has recently developed as a strategy for mitigating drought in the dryland regions of the western Central Great Plains. Here we compare 16 site-years of no-till feed grain yields when planted skip-row and when planted conventionally in Eastern Colorado and Western Kansas (over half of the locations were on farm replicated trials. The idea is that a wider row arrangement forces a change in the timing of soil-water availability and use, which may mitigate d... M. Vigil, B. Henry, F. Calderón, D. Poss, D. Nielsen, J. Benajmin, B. Klein

4. Achieving Economic and Greenhouse Gas Goals Through Tillage and N Management

A field study was conducted near Ft. Collins, CO evaluating irrigated continuous corn production under conventional tillage (CT) and no-till (NT) with six N fertilizer application rate treatments. Economic return response functions were developed for each tillage system and combined with net global warming potential estimates for a subset of treatments to determine whether economic and greenhouse gas emission improvements could be achieved. Results show economic returns can be increased by $1... D. Archer, A. Halvorson

5. Agriculture’s Contribution to Nitrogen Deposition in Rocky Mountain National Park

Nitrogen deposition in Rocky Mountain National Park has been increasing steadily and is impacting both terrestrial and aquatic ecosystems.  Ammonia volatilization from fertilizer is estimated to contribute 20% of the N deposited in the park.  The objectives of our research are 1) to determine N isotope ratios for ammonia sources, and to use this tool to evaluate the accuracy of the source predictions, and 2) to evaluate Best Management Practices for ammonia volatilization ... J. Davis, T. Borch, N. Marcillac

6. Biofuels and Nutrient Management

Few developments have had as dramatic or rapid an impact on crop production as did grain-based ethanol on corn in 2006 and 2007. In response to strong market signals, corn acreage in the U.S. in 2007 jumped from a three-year average of 80 million acres to nearly 93 million, an increase of more than 15%. Secondary effects on prices of other commodities soon followed. Nutrient demand increased as well as the cost of many inputs needed for crop production. The purpose of this paper is to evaluat... P. Fixen

7. Calibration of the Nitrate Soil Test for Malting Barley in Western North Dakota

Malting barley production is moving westward into semi-arid regions, such as western North Dakota.   The objective of this study was to determine if the “nitrogen factor” traditionally used for malting barley in eastern ND, 1.5 lb (soil nitrate + fertilizer)-N per bushel, was valid for western ND.  Six experiments were conducted.  At each site, twenty unique combinations of residual nitrate-N and fertilizer N were combined with two varieties, a 6... J. Goos, B. Johnson, E. Eriksmoen, J. Nelson, G. Martin, P. Carr, N. Riveland, G. Bradbury

8. Copper and Zinc Fertilization in Winter Wheat

Copper and zinc applications have recently been sited as a possible management practice to improve wheat production on the Great Plains.  Copper deficiency has been observed on wheat planted into peat soils, whereas wheat sensitivity to zinc deficiency is rated as low.  To determine whether winter wheat in Kansas may benefit from copper and zinc, a multi-site study was set-up to determine if a 1 lb/a application applied prior to jointing is beneficial to yield.  ... B. Olson, K. Leikam, M. Claassen

9. Dryland Corn Yield and Water Use Affected by Seeding Rate and Row Configuration

An established cattle market in the Northern Great Plains (NGP) creates a demand for feed grains including corn grain and silage.  However, dryland corn production is hampered by the risk of crop failure due to drought conditions.  Altering the row configuration and seeding rate have reduced the risk of yield loss in other areas, but these typically receive greater rainfall than the average 12-14 in annual precipitation of the NGP.  A study was initiated in 2007 ... B. Allen

10. Estimating Canola (Brassica Napus L.) Yield Potential and Nitrogen Requirements Using Optical Sensors

Optical sensors have potential to improve our ability to match N fertilizer rates with crop requirements.  Experiments with canola (Brassica napus L.) were completed to determine if normalized difference vegetation index (NDVI) could be used to estimate canola yield potential (YP) and N requirements, as well as to assess if sensor-based N management for canola is feasible relative to conventional practices.  Canola plots were repeatedly measured with handheld GreenSee... C. Holzapfel, G. Lafond, S. Brandt, R. Irvine, D. James, M. Morrison, W. May, P. Bullock

11. Fertilizer Placement with Seed – a Decision Aid

Banding fertilizers with the seed at planting continues to be a popular option with producers in the Great Plains and North Central regions of the U.S.  However, seed-placed fertilizer may limit germination/emergence of the seed/seedling.  Nutrient source and rate are two factors affecting injury that are relatively simple to manage. Unfortunately, many crop producers and advisors have few rate guidelines for the many crop by fertilizer combinations that are common to... R. Gelderman

12. Foliar Potassium Fertilization of Muskmelons: Effects on Fruit Quality and Yield

Sugar content, aroma and texture are key quality traits that influence consumer preference of many fruits and vegetables such as muskmelon [Cucumis melo L. (Reticulatus Group)].  These quality traits are directly related to potassium (K)-mediated processes.  However, soil-derived K alone is seldom adequate to satisfy these fruit quality processes.  Controlled environment studies have shown that supplemental foliar K applications can overcome this apparent de... J. Jifon, G. Lester

13. Impact of Grid Point Sampling Intensity on Phosphorus and Potassium Uncertainty

Soil testing is the foundation for the determination of nutrients for crop recommendations.  The reliability of which is based the collection of a representative field sample, appropriate test method, accurate laboratory analysis, and the nutrient recommendations.  The success of the soil testing process is fundamentally dependent on the collection of a representative soil sample.  For whole fields this entails a composite of multiple soil cores denoting the coll... R. Miller

14. Impact of Growth Hormones on Nutrient Excretion

The U.S. Food and Drug Administration (FDA) first approved the use of hormone implants containing estradiol benzoate/progesterone in 1956 for increasing growth, feed efficiency, and carcass leanness of cattle.  Livestock production sites, including feedlots and dairies have recently undergone close scrutiny for their contribution of endocrine disruptor residues to the environment via their manure.  While these effects need to be addressed, there is also a definite impact o... S. Archibequet, T. Borch, J. Davis

15. Impacts of Cropping Intensity on Soil C and Net Greenhouse Gas Fluxes for Dryland Cropping in Northeastern Colorado

In 1985, land that was traditionally used for conventional tillage wheat/fallow cropping was converted to no till alternative cropping systems to investigate soil carbon changes.  After 12 years of average to above average precipitation, continuous no till cropping with out summer fallow had stored more than twice the amount of carbon in soil compared to no till wheat/corn/fallow cropping. However, after 18 years, the wheat/corn/fallow system had stored almost 3 times as much carbon... S. Del grosso, L. Sherrod, A. Mosier, G. Peterson, L. Ahuja, N. Hansen

16. Inclusion of Weather and Soil Data in Nitrogen Yield Response Curves and Economic Models

Near record-high fertilizer prices have created the need for models that predict economically optimum nitrogen (N) fertilizer rates for small grains in Montana. Current yield and protein models, necessary for the development of economic models, have been based on available N (soil plus fertilizer N) and grouped into two to three yield ranges to improve model fit. The goal of this study was to add climate parameters and organic matter (O.M.) content into grain yield, protein, and economic mode... C. Jones, D. Griffith

17. Land Application of Anaerobically Digested Biosolids in Usepa Region 8

Most municipal wastewater in USEPA Region 8 (covering the states of CO, MT, ND, SD, UT, and WY) flows through facilities where the sludge is treated using anaerobic digestion in order to meet pathogen reduction and vector attractiveness requirements.  Tracking the application of anaerobically digested biosolids is an important step in determining the fate of carbon, nutrients, and potential contaminants from this widely used biosolids treatment process.  The biosolids appl... R. Brobst, M. Massey, W. Kennedy, L. Shanklin

18. Long-term Phosphorus Studies in Western Canada

An experiment that was established in 1982 to assess placement of P fertilizer on the yield of continuous barley was terminated in 2004, after annual application of P (30 kg ha-1) was discontinued in all but one treatment in 2001.  Total removal of P during the first 20 years of the experiment (615 kg P2O5 ha-1) was virtually equal to total P application (600 kg P2O5 ha-1); however, when removal by the control that was fertilized with N only was subtracted from the total r... R. Karamanos

19. Meeting Demand with a New Interdisciplinary Program in Organic Agriculture

Organic food and fiber production without the use of synthetic pesticides or chemical fertilizers is the fastest-growing sector of the agricultural industry, fueled by consumer demand. The Interdisciplinary Studies Program in Organic Agriculture at Colorado State University provides a unique opportunity to study the science of organic production. Our program builds on a base of fundamental agricultural sciences with additional courses on organic agricultural methods, management and marketing.... A. Elliott, F. Stonaker, J. Davis, H. Hughes

20. Microbial Communities and C Cycling Under Deficit-irrigated Maize

Growing urban population, declining groundwater levels, and drought are factors leading to reduced water quantities for irrigated land in the semiarid western U.S.  Developing sustainable limited irrigation systems necessitates an understanding of how reduced water availability affects soil microbial processes and ecological interactions critical to crop productivity and soil conservation. The objective of this study was to determine the effects of deficit-irrigated maize cropping s... M. Stromberger, K. Coffin, N. Hansen

21. Nitrogen Fertilization Effects on Nitrous Oxide Emissions from Irrigated Cropping Systems

We evaluated the effects of N fertilization and irrigated crop management practices on nitrous oxide (N2O) emissions.   Emissions were monitored from several irrigated cropping systems receiving N fertilizer rates (0, 67, 134, and 246 kg N/ha) during the 2006 growing season and N rates of 0 and 246 kg N/ha on corn plots, 0 and 156 kg N/ha on barley plots, and 0 and 56 kg N/ha on the dry bean plots during the 2007 growing seasons.  Cropping systems included: convention... A. Halvorson, S. Del grosso, C. Reule

22. Nitrogen Management for No-tillage Corn and Grain Sorghum Production

No-tillage production systems are being used by an increasing number of producers in the central Great Plains because of several advantages that include reduction of soil erosion, increased soil water use-efficiency, and improved soil quality. However, the large amount of residue left on the soil surface can make nitrogen management difficult. Surface applications of urea containing fertilizers are subject to volatilization losses. Leaching can also be a problem on course textured soils when ... B. Gordon

23. Nitrogen Mineralization Rate of Animal Manure Across Productivity Level Management Zones

Accurate quantification of Nitrogen (N) mineralization in manure from different productivity level management zones (MZs) could result in efficient and safe utilization of manure as N fertilizer. Soil characteristics and crop responses change between different MZs and the loss of N and other nutrients into the environment can occur when the supply of soil nutrients by animal manure and other sources exceeds the demand by crops. The objective of this study was to compare nitrogen mineralizatio... M. Moshia, R. Khosla, D. Westfall, J. Davis, R. Reich

24. Nitrogen Recalibration for Wheat in North Dakota

The general formula for determining N fertilizer rate in North Dakota for about thirty-five years has been N-rate = (2.5 X Yield Potential (or Yield Goal) less credits from previous crops and soil test nitrate-N from a 2-foot soil core composite. Historically high fertilizer N costs and the ability to fertilize within fields rather than whole field N management has resulted in a reexamination of N calibration data, and an effort to expand the modern N calibration database with new f... D. Franzen, G. Endres, K. Mckay, J. Lukach, R. Ashley

25. Nitrogen Requirements of Sorghums for Biofuel Feedstock Production in the Southern High Plains

Sorghums are a logical crop choice for biofuel feedstock in semiarid West Texas.  The declining Ogallala aquifer means that “renewable” biofuel production must be on limited irrigation.  Nutrient requirements, primarily N, become the next constraint.  We looked at total biomass yields, grain yields, estimated ethanol production, and brix content of forage sorghums, grain sorghums, and sweet sorghums from 2004 to 2007 in Bushland, Texas.  Bio... B. Bean, K. Bronson, R. Schwartz, A. Malapati

26. Nutrient Uptake and Manganese Response in Conventional and Glyphosate-resistant Soybean

Glyphosate-resistant (GR) soybean cultivars are widely accepted in the United States. Glyphosate-resistant technology provides many benefits to production agriculture, yet GR soybeans may require some additional management factors in order to obtain maximum yields. The objectives of this research are to determine (i) nutrient uptake in GR and conventional (CV) soybean isogenetic lines and (ii) response of GR and CV soybean to manganese fertilization. A field study was conducted at 5 locations... J. Loecker, N. Nelson, W. Gordon, L. Maddox, K. Janssen

27. Phosphorus Placement in Reduced Tillage Systems in Kansas

A number of questions are being raised concerning phosphorus (P) management as more producers switch to minimum or no-till (NT) systems.  These tillage systems conserve moisture below the surface residue creating cooler, and potentially wetter soil conditions at planting, and stratified nutrient concentrations in the soil.  The cooler temperatures can result in slower earlier season growth on crops such as corn and wheat, and P stratification can potentially reduce P uptak... K. Martin, D. Mengel

28. Quick Test for Cation Exchange Capacity in Soils

The objective of this study was to develop a quick method for estimating the cation exchange capacity (CEC) of soils, suitable for use in an introductory soil science laboratory, and possibly for routine soil testing.  In this method, the soil is reacted with a calcium solution, such as calcium acetate, and the excess removed by filtration.  The soil is then suspended in a sodium oxalate solution, and the electrical conductivity (EC) of the suspension determined. &nbs... J. Goos, B. Johnson

29. Residual Effects of Manure and N Fertilizer on Corn Yield and Soil N and P Under Drip and Furrow Irrigation

A field experiment was conducted at the Arkansas Valley Research Center in 2007 to test the residual effects of two years (2005 and 2006) of manure application (10, 20, and 30 tons/acre) and N fertilizer (60, 120, and 180 lb N/acre) on corn yield, N and P uptake, and soil N03-N and P concentrations under subsurface drip irrigation (SDI) and furrow irrigation (FrI).  There were no significant differences in corn yield between SDI and FrI in 2005, 2006, and 2007, even though, on avera... A. Berrada, A. Halvorson, M. Bartolo, J. Valliant

30. Response of Camelina to Nitrogen, Phosphorus, and Sulfur

Camelina (Camelina sativa) has been introduced as feed stock for bio-products, but information about its nutrient requirements are lacking. Experiments were initiated to determine the seed yield, seed oil, N, P, K, and S content, and fatty acid composition of the oil response of camelina to N, P, and S additions and to determine if the response is related to appropriate soil tests. Data from six locations indicated that camelina needs about 80 lbs N/acre for optimum seed yields and oil c... G. Jackson

31. Seedrow Nitrogen Placement Guidelines

Introduction of no-till and direct seeding practices in the western Canadian prairies has resulted in expansion of the practice of placing N fertilizer with the seed.  Almost fifty percent (49.5%) of the total seeded acres in western Canada were in no-till according to the 2006 census (Statistics Canada 2006).  Greatest percentages were in Saskatchewan and Alberta, where no-till systems accounted for 60 and 48 % of the seeded area, respectively. ... R. Karamanos, J. Harapiak, N. Flore

32. Sorghum Grain Yield and Yield Component Under Different Skip-row Configuration and Plant Density in Nebraska

Equal spacing of sorghum rows typically results in the highest grain yield when soil water is adequate throughout the season, but skip-row planting may be a means to reduce water deficits during reproductive growth stages. A two year field study was conducted to evaluate the effect of skip-row configuration and plant population density on grain yield and yield components in a transect across Nebraska where annual mean precipitation ranges from 300 to 900 mm yr-1. Three row configurations incl... A. Abunyewa, R. Ferguson, C. Wortmann, D. Lyon, S. Mason

33. Strip Tillage for Sugarbeet and Its Implications for N Fertilizer Management

Strip tillage (ST) is attractive as a means to reduce fuel and labor costs associated with sugarbeet (Beta vulgarisL.) production, but seedbed preparation, fertilizer management, and weed control are concerns. A field study was conducted near Sidney, MT with objectives to (i) compare the effect of tillage system [conventional tillage (CT) vs. ST] on yield and quality, and (ii) compare N uptake and availability with the two tillage systems under sprinkler irrigation. For ST, 12-inch strips spa... B. Stevens, B. Iversen, B. Evans, J. Jabro, J. Kim

34. Strip Tillage Versus Broadcast N Application for Sugar Beet and Dry Beans

Strip-till placement of N was compared to broadcast N application for sugar beets and dry beans during 2006 and 2007 near Scottsbluff, NE.  Effects on sugar beet stand, yield, sugar content and sucrose production and sugar loss to molasses were evaluated.  For dry beans, stand and final yield effects were measured.  No significant N method effects or N rate by method interactions were shown for either crop.  N rate significantly increased yield of both ... G. Hergert, R. Nielsen

35. The Effectiveness of Recovered Phosphates As Fertilizer in Slightly Acidic and Alkaline Soil Conditions

Recovered magnesium phosphates such as struvite (MgNH4PO4·6H2O) may be useful as a method of improving phosphorus (P) cycling in municipal wastewater treatment and livestock agriculture.  However, little work has been done on the re-use of recovered products, and what work has been conducted has focused on low pH soils.  This study was conducted to determine if recovered struvite and recovered dittmarite (MgNH4PO4·H2O) are effective fertilizers in alkaline so... M. Massey, J. Davis, R. Sheffield

36. The Effects of Compost, Manure, and Urea on Yield and Forage Quality when Topdressed on a Perennial Forage Mix of Irrigated, Cool Season Grasses

Significant quantities of animal manures are generated by livestock and equine facilities along the Front Range in Colorado.  Topdressing raw manure on perennial forage is not recommended due to high potential losses of N into the atmosphere and surface water.  Composted manure contains significantly less ammonium-N than raw manure.  In a 2 year study conducted to determine the effects of topdressing composted manure, raw manure and urea on the yield and forage q... K. Doesken, J. Davis, J. Brummer, T. Engle

37. The Implications of Biofuel Production on Soil Productivity

Production of biomass from agricultural crops as a source of energy generated either as a primary or secondary source from agricultural systems has the potential to provide a portion of the nation’s energy needs. Removal of crop residue after harvest is viewed as a major source of cellulosic material; there are challenges that arise with biomass removal in cropping systems in which the crop residue has remained on the soil surface after harvest.  The potential impacts of bioma... J. Hatfield

38. The Use of Active Optical Sensors to Manage N Fertilization of Sorghum in Kansas

Research in the Central Plains region has shown grain sorghum (Sorghum bicolor L. Moench) to be more tolerant of water-stress than corn (Zea mays L.). As a consequence sorghum is commonly grown in the region in rotation with winter wheat (Triticum aestivum L.) and soybeans (Glycine max) in areas and soils where corn does not perform well due to regular drought stress.  Sorghum yields vary widely from year to year, making traditional pre-plant, yield goal based, N reco... D. Tucker, D. Mengel

39. Tifton 85 Bermudagrass Response to Potassium, Chloride and Sulfur at Two Nitrogen Rates

‘Tifton 85’ is a relatively new bermudagrass (Cynodon dactylon (L) Pers.) hybrid with improved nutritive value and yield potential.  Limited plant nutrient response data are available for this grass.  We designed field research to evaluate the response of Tifton 85 to K, Cl, and S at two N rates.  Tifton 85 was sprigged in spring 2001 on limed Darco loamy fine sand (Loamy siliceous semiactive thermic Grossarenic Paleudult) fertilized with 68 lb o... V. Haby, W. Stewart, A. Leonard

40. Tillage, Cropping Sequence, and Nitrogen Fertilization Effects on Dryland Soil Nitrogen and Malt Barley Yield

Information on management practices is needed to reduce N fertilization rate and soil erosion and sustain dryland malt barley yield and quality in the northern Great Plains. The effects of combinations of tillage and cropping sequences [continuous no-tilled malt barley (Hordeum vulgaris L.)(CNTB), no-tilled malt barley-pea (Pisum sativum L.) (NTB-P), no-tilled malt barley-fallow (NTB-F), and conventional-tilled malt barley-fallow (CTB-F)] and N fertilization rates (0, 40, 80, and 12... U. Sainju

41. Update on Using Active Sensors to Manage N Application on Corn

We are testing a prototype high-clearance N applicator configured with active crop canopy sensors, electronic valves, and a variable rate controller to deliver in-season variable rates of nitrogen (N) fertilizer based on crop needs in lieu of uniform at-planting N applications.  The active sensor used is the Crop Circle model ACS-210 manufactured by Holland Scientific (Lincoln, NE), and it measures canopy reflectance in the visible (cente... J. Shanahan, J. Schepers, R. Ferguson, D. Roberts

42. Validation of the Pre-sidedress Nitrate Test for Poultry Manured Corn Fields

Previous research in northeastern Colorado has shown that the critical Pre-sidedress Nitrate Test (PSNT) level to obtain optimum corn (Zea mays L.) grain yields without applying additional sidedress N on non-manured fields is 15 mg kg-1 nitrate-nitrogen (NO3-N).  This study was conducted to determine if the critical PSNT level of NO3-N identified for non-manured corn fields would also apply to those fields receiving an organic N source before planting. The effect of PSNT levels... T. Bauder, D. Quarles, R. Pearson, S. Van wychen

43. Wheat Roots and Residue Effects on Soil Aggregation and Carbon

Crop residues have been identified for a number of off-field uses. Poor understanding of the role of crop residues in key soil processes limits our ability to predict sustainable crop residue removal rates. A study was conducted to compare aggregate size distribution, aggregate stability, and soil organic carbon fractions in the 0 to 3 inch depth of soils receiving surface residue and roots, surface residue only, roots only, or no residue for five years. Aggregate size distribution was simila... B. Wienhold, W. Wilhelm

44. Winter Canola Fertility for the East Central Great Plains

The objective of this research is to develop Nitrogen recommendations for winter canola (Brassica napus L.) grown in the southern Great Plains.  This work focuses on timing: fall, spring, or split; the possible benefits of sulfur application, and the effect of fall fertilizer N on winter survival.  Studies were conducted at three sites in Kansas (one experiment field and two cooperator sites) and one research farm in Oklahoma.  Applied N (urea and/or ammoniu... V. Martin, W. Heer, D. Mengel, C. Godsey