Proceedings
Year
| Filter results60 paper(s) found. |
|---|
1. A Combination of Soil Incubation and Chemical Extraction Tests Best Predicts Corn Yield Response to Fertilizer NitrogenSoil tests in general have served a critical role in the field of soil fertility for over half a century, and have helped to increase crop productivity and promote more efficient use of fertilizers on farms. However, N soil tests have limitations and chemical extraction tests have not predicted well the potentially mineralizable N supplied to corn over a growing season. Thus, these tests often do not accurately predict a corn’s yield response to fertilizer N. We explored 30 soil tests f... M. Mcdaniel, D. Walters, L. Bundy, C. Laboski, P. Scharf, R. Drijber, W. Horwath, J. Sawyer, J. Sawyer, M. Castellano |
2. A Systems Approach to High Yields, Efficiency and Profits in Corn, Wheat and Doublecropped Soybean RotationUsing a systems approach friendly to the environment, a three-crop/two-year no-till system has shown significiant yield increases in a three-year research project conducted at the Poplar Hill Research and Education Facility in Quantico, Maryland. In each case, corn, wheat, and doublecropped soybean yields exceeded average yields produced on Maryland's Delmarva Peninsula. Instrumental in producing these superior yields were enhanced fertility, supplemental water, and appropriate variety selection... |
3. Agronomic and Nutrient Management Strategies for Soft Red Winter WheatMichigan produces some of the greatest non-irrigated wheat (Triticum aestivum L.) yields in the United States. Enhancing or lengthening the greenness of the flag-leaf has been suggested as a method to improve photosynthetic capabilities and nutrient uptake. The objective of this study was to evaluate growth, grain quality, grain yield, and economic profitability for multiple agronomic and nutrient inputs across different production intensity levels. An omission field trial with four repl... S. Purucker, K. Steinke |
4. Assessment of Plant Nitrogen Uptake with Late Fertilizer Applications in CornPrevious research in Kansas and other regions has shown that split applications of N fertilizer with early side-dress can increase yield compared to applications at planting in some site years. Split applications are typically done using the traditional side dress at the V6-V8 growth stage. However, late N applications (late-vegetative or early reproductive stage) is generating interest as one alternative to improve nitrogen use efficiency and possibly increase yields... D. Diaz, A. Stammer, F. Hansel |
5. Biological N Fixation on Soybeans: N Nutrition and Incidence on N BalanceSoybean [Glycine max (L.) Merr.] nitrogen (N) demand is partially met (50-60%) by the biological N fixation (BNF) process. Study of the “N-gap” (plant N demand minus N-BNF) and the partial N balance (fixed N in aboveground biomass minus N removed by seeds) are still unanswered scientific knowledge gaps. Focusing on these two components a review of 60 studies reporting on BNF was conducted in order to study the limits to which BNF can satisfy plant N demand. T... I. Ciampitti |
6. Can an Estimate of Mineralizable Nitrogen Improve Nitrogen Sufficiency Indexes?Combining the anaerobic potentially mineralizable N (PMNan) test with the pre-plant (PPNT) and pre-sidedress (PSNT) nitrate tests may improve N fertilizer guidelines for corn (Zea mays L.). Forty-nine corn N response experiments were conducted across eight states in the US Midwest (Illinois, Indiana, Iowa, Minnesota, Missouri, Nebraska, North Dakota, and Wisconsin) from 2014-2016. These studies were used to evaluate the effect of combining PMNan values from different soil sampling t... J. Clark |
7. Can Co-additives Alter the Phosphorus Fertilizer Reaction Pathways in P-Fixing Soils?In many calcareous and strongly weathered acid soils, only a small proportion of applied fertilizer P is available for plants in the year of application due to rapid transformation of applied P to insoluble forms (“fixed” P) with limited plantavailability. The residual effectiveness of applied P fertilizer decline over time due to further transformation of applied P to more insoluble forms. High nutrient loading intended to overcome P availability limitations in high P-f... G. Hettiarachchi |
8. Can Nitrapyrin and Cover Crop Improve Fall Dairy Slurry N Availability to Corn?Fall applications of manure have the potential for high nitrogen (N) losses. Cereal/grass cover crops have been shown to take up fall applied N. Similarly, using nitrapyrin (Instinct®) has been shown to prevent loss of fall applied N. No studies have been conducted to evaluate combining these tools to prevent N loss. This experiment was performed in 2016 and 2017 on a well-drained and somewhat poorly drained silt loam soils. This study was conducted to determine if using Instinct®... A. Teeter, T. Andraski, C. Laboski |
9. Carbon and Nitrogen Dynamics: Cover Crop Decomposition during the Following Cash Crop Growing SeasonNitrogen (N) loss from agriculture fields in the Corn Belt contributes to impaired waterways and the development of the “Dead Zone” in the Gulf of Mexico. It has been well established that cover crops can scavenge N, which results in a reduction of N loss via tile drainage. However, the literature suggests that increased C inputs from decomposing cover crop residue may result in N immobilization during the following cash crop growing season andnegative yield impacts. Therefore, th... C. Lacey |
10. Comparing the Performance of Preplant and Presidedress Soil Nitrate Tests for the North-Central RegionSoil nitrate (NO3-N) testing is a recommended best management practice (BMP) for adjusting corn N fertilization rates across the North-Central region. Several approaches to soil NO3-N testing are used and vary in both recommended time and depth of sampling (Hergert, 1987). Nitrate is very mobile in soil and is subject to either loss from leaching and denitrification or gain from net mineralization of crop residue and manure. The processes that govem nitrate accumulation in soils are most active ... |
11. Comparison of Mehlich-3, Olsen, and Bray-P1 Procedures for Phosphorus in Calcareous SoilsFertilizer recommendations for P generally are based on soil testing. Although a variety of soil tests are reliable for evaluating plant available P of neutral or slightly acid soils. there is still uncertainty about appropriate soil tests and soil-test interpretations for calcareous soils. The Bray-P 1 and Olsen methods are the most widely used soil-test P methods in the North Central region. Extensive research has shown that the Bray-P1 test is reliable on neutral or acid soils but that it ten... |
12. Corn Nitrogen Management Following Cover Crops and the Microbial ResponseCover crops (CCs) may provide tools for fertilizer management and opportunities to influence soil biological communities. However, corn (Zea mays L.) growth and microbial response remain unclear when corn nitrogen (N) management strategies are practiced in combination with specific CCs. Field studies were conducted in 2015 and 2016 to evaluate the effects of no CC, Daikon radish [Raphanus sativus (L). var. The Buster], and Forage oat [Avena sativa (L.) var. Magnu... K. Steinke, J. Rutan |
13. Corn Production as Affected by Daily Fertilization with Ammonium, Nitrate, and PhosphorusManipulation of N fertilization to control NH,+/NO,' ratios in the soil can affect corn (Zea mqs L.) growth and yield. Field study of these effects, however, has been difficult to conduct because nitrification of NH,+ andlor NO, leaching often occurs during the growing season. The objectives of this 4-year field experiment, were to investigate the effects of daily fertilization with various N sources and P on corn growth and yield. Pioneer 3343 was fertilized with solutions of urea (U), NH,CI, C... |
14. Corn, Rye, and NitrogenThe U.S. still has an erosion problem. Half of the topsoil is gone over much of the Midwestern U.S., and erosion continues at an unacceptable rate. Protecting soil after soybean is grown is the weakest link in the chain because soybean leaves so little residue that even with no tillage the soil is vulnerable. Cover crops offer great promise to solve this problem. Rye is cheap, hardy, grows well in cool fall weather, and is easy to kill, but evidence continues to mount that rye causes yield lo... P. Scharf |
15. Correlation Between Mehlich-3 and Haney Extractable Phosphorus and Potassium, and Their Relationship to Soybean (Glycine Max) Yield ResponseNumerous soil tests have been developed for estimating the plant-availability of soil phosphorus (P) and potassium (K). Understanding the relationship between these test’s results and crop response to fertilizer application is essential for developing and improving fertilizer recommendations. Field trials have been initiated at six sites located across the state of Kansas to investigate the response of soybean to broadcast P and K fertilizer application. Plots a... E. Rutter, D. Ruiz diaz, F. Hansel |
16. Correlation of the Weak Organic Acids Test of a Soil Health Tool with Crop Yield Response to Phosphorus FertilizationThe field correlation of a soil P test with yield response to P fertilization is the foundation for sound soil-test interpretations and fertilizer recommendation guidelines. Weak organic acid extractants have been used to measure soil P for decades in some northeastern states of the US and other countries, but not in Iowa or the Midwest. A new test based on a mixture of malic, oxalic, and citric acids (H3A) was developed as a component of a Soil Health Tool to measure soil P and K. The H... A. Mallarino, J. Jones |
17. Cover Crop and Nitrogen Fertilizer Rate Effects on Mitigating Soil Nitrate Leaching in Irrigated Sandy Soils in Corn and Soybean ProductionCoarse textured soils are very productive when supplemented with irrigation and nitrogen (N); however, they are susceptible to nitrate (NO3–N) leaching. Nitrate leaching not only reduces fertilizer efficiency but has costly environmental impacts to the groundwater supply. The majority of NO3–N loss occurs in the fall and spring or when nutrient and water uptake from corn (Zea mays L.) and soybean (Glycine max Merr. L.) is limited but precipitation is fr... N. Ricks, F. Fernandez |
18. Cover Crops Impact on Biomass, Yield, Soil Health, and Nutrient Loss in a Tile-Terrace FieldSoil erosion by water can be the most important land degradation process on erodible to highly erodible soils. Therefore, different conservation practices can be implemented to address the issue including no-tillage, cover crops (CC), grass filter strips, riparian buffers, and terraces. A field trial was established at the University of Missouri Grace Greenley Research Center near Novelty to evaluate the impact of CC and no-CC (non-treated control, NTC) on crop yields, soil health, and water ... R. Adler, G. Singh, K. Nelson |
19. Does it Pay to Sidedress Some of the Nitrogen on Corn?Dividing the amount of nitrogen fertilizer applied to corn over two or three applications has become a common practice, based on the understanding that waiting to apply some of the N lowers the potential for loss of N, and that applying N during vegetative growth stages enables N to get into the plant quickly when the plant is rapidly taking up N. Across 20 sites, spring preplant ammonia at 200 lb. N/acre, fall-applied ammonia at 100 lb. N/acre + 50 lb. N as UAN injected at planting + 50... E. Nafziger |
20. Effects of Residue Density, Strip Tillage, and Starter K on No-till Corn Grown in Wheat StubbleField studies were conducted in 1992 to 1994 at 2 locations in southern Illinois to evaluate the influence of wheat straw residue density and stl-ip-tillage vs no-tillage on corn growth and yield. Corn growth and resultant yield is frequently reported by producers to Se depressed in the residues of a previous wheat crop. Allelopatliy is thought to be at least partially involved. The objective of the research was to evaluate straw level (removed, remain non-modif ied, and doubled), strip tillage,... |
21. Effects of Sampling Time and Extraction Method on Soil-Test and Nonexchangeable Potassium in Iowa SoilsMore research is needed to better understand K cycling and high short-term temporal soil-test K (STK) variation. The objective of this research was to study soil-test K and nonexchangeable K pools across Iowa soils managed with corn-soybean rotations as affected by K application rates, soil properties, parent materials, and time of sampling. Three-year field trials that included a control and several broadcast K fertilizer rates were conducted at 35 Iowa sites. Soil samples (6-inch depth) wer... R. Oltmans, A. Mallarino |
22. Estimation of Nitrogen Losses from Char Amended Fertilized Soils: a Laboratory StudyMore than 50% of nitrogen (N) fertilizer added to agricultural soil is lost to the environment through volatilization, denitrification, and leaching. Proper management of soil carbon (C) may reduce N losses since soil C affects soil properties and N cycling. There are a wide range of soil C management practices, including direct addition of high C content materials to the soil. A 30-day laboratory study was conducted to evaluate effects of char on N losses from fertilized loam and sandy loam ... D. Panday, B. Maharjan |
23. Evaluation of Potassium Fertilization Strategies for Corn and Soybean: the Buildup PhasePotassium is a crop nutrient which can severely limit yield potential when deficient. Potassium fertilizer historically was low cost. Price increases have resulted in more questions as to the benefit from potassium applied for corn and soybean. The objective of this study was establish a set of trials which vary in soil test K level to be used to determine corn and soybean grain yield response to K based on initial soil test and to compare soil K analysis on moist versus air dried soil sample... J. Vetsch, D. Kaiser |
24. Fertilizer Management of Soybean in Northwestern and Northcentral North DakotaSoybean (Glycine max L.) is a new cash crop for northcentral and northwestern North Dakota (ND) producers. Soils and climate in these new soybean areas differ from current fertilizer guidelines. North central and northwestern ND is more undulating, arid, cooler, and has differing soil pH. A three year study to evaluate soybean best management practices was initiated in the spring of 2016 and will be concluded in 2018. Each year had two sites and twelve treatments. One site was acidic (pH... C. Augustin, D. Franzen |
25. Forage Quality Management- A Key to Successful Cattle Nutrition ProgramsIn 1992, the USDA reported 59.6 million acres were harvested for hay with an average yield per acre of 2.5 ton per acre. These values gave a projected total yield of 149.1 million tons of harvested hay. Using an average market price of $72.10 per ton, total value of hay produced exceeded 10.5 billion dollars. Also in 1992, alfalfa production represented over 50 percent of the forage harvested with 79.6 million tons produced. In addition to stored forage. pasture is also a significant source of f... |
26. Grid Soil Sample Interpolation Using Geographicaly Weighted Regression and Random ForestSoil sampling is useful in agriculture for setting fertilizer application rates. High density soil samples can also be used for variable rate seeding and other precision agriculture applications. Half-acre grid soil samples were collected from 6 soybean fields, and phosphorous (P), potassium (K), and organic matter (OM) were measured. Each soil parameter was interpolated for each field, with terrain attributes as covariates, using two different methods: geographically weighted regression (GWR... E. Matcham, S. Subburayalu, J. Fulton, E. Hawkins, P. Paul, L. Lindsey |
27. How Late Can Nitrogen Be Applied to Corn?Delaying some of the N supplied to the corn crop is considered a way to increase N uptake and yield and to limit N losses, but the length of the delay may increase the risk of yield loss. We conducted a 3-year experiment at Urbana, Illinois in which half of the N (112 kg N/ha) was injected as UAN at planting and the other half or all (224 kg N/ha) of the N was dribbled UAN next to the row, at each of eight stages ranging from V3 to R3. In corn following soybean, when half of the N was applied... B. Yoder |
28. Improving PSNT Based Sidedress N Recommendations for Corn with Site Specific FactorsThe pre-sidedress soil nitrate test (PSNT) has been found to be a valuable tool for improving nitrogen recommendations for corn grown in humid regions of the country. The PSNT has been especially useful for nunaging N on fmls where organic sources of N, like animal manures are important. This test was proposed by Magdoff et al. in 1984 and has been studied extensively since then (Magdoff et al., 1990; Roth et al., 1992; Fox et al., 1989; Blackmer et al., 1989; Klausner et a]., 1993, and Meisinge... |
29. Influence of Potassium, Sulfur, and Zinc Fertilizer on Corn and Soybean Grown on High Tetsing SoilThe influence of potassium, sulfur and zinc fertilizer on corn and soybean yields grown on high testing soils was studied at two locations in Eastern South Dakota over a period of six years. Treatments were 50 Ibla K,O, 25 Ibla sulfur and 5 Ib/a zinc. The treatments were applied to the same plots at each location every year. Soil test levels were in the high range for all elements in question and additional nutrients would not have been recommended by the South Dakota State University Soil Testi... |
30. Manure, Phosphorus, and 125 Site-Years of Edge-of-Field Runoff MeasurementsPhosphorus export from agricultural fields continues to create water quality concerns in Wisconsin. The UW Discovery Farms program, along with Discovery Farms Minnesota have collected 125 site-years of edge-of-field monitoring datawhich can be used to better understand the relative effects of inherent soil properties (slope, drainage class, texture), management practices (manure application, tillage, crop rotation, cover cropping), and soil test P values on seasonal (frozen and non-... M. Ruark, A. Thompson, Z. Zopp, T. Radatz, A. Radatz, E. Cooley |
31. Nitrogen Availability and Corn Production in Minnesota Following Cover CropsCover crops are often included in BMPs for reducing soil erosion, building soil organic matter, and reducing nitrate leaching. Because of additional management requirement and uncertainties about their impact on nitrogen availability and cash crop yields, cover crops have not been widely adopted in conventional fields. This study aims to reduce these uncertainties for corn growers in Minnesota by measuring the impact of select cover crops on corn yield, nitrogen ... S. Badger |
32. Nitrogen Management in Minnesota as Influenced by Soil Drainage and TillageTile-draining, conventional tillage and pre-plant applications of nitrogen (N) fertilizer are prevalent practices among Minnesota corn growers. However, climate change and increasingly warmer and wetter spring conditions have called for a re- evaluation of the appropriateness of these practices for continued sustainable corn production. The objectives of this study are to determine the influence of drainage, tillage and N application timing on (1) corn grain yield and N uptake, (2) corn N dem... G. Paiao, F. Fernandez |
33. Nitrogen Non-Cycling from Cover Crops Grown Before Corn and Spring Wheat-Unexpected Early Project ResultsNitrogen credits in North Dakota State University fertilization recommendations include those anticipated from the previous year annual legume crops (field pea, lentil, soybean, chickpea) and from terminated alfalfa. In addition, it was established in the region that sugarbeet tops returned to the soil may have an N credit potential of up to 80 pounds of N per acre (Crohain and Rixhon, 1967; Moraghan and Smith, 1994a; Moraghan and Smith, 1995a; Moraghan and Smith, 1995b; Franzen et ... D. Franzen, A. Wick, H. Bu, L. Ressler, J. Bell, M. Berti, C. Gasch |
34. Nitrogen Source and Timing Effects on CornThe 4R’s of nutrient management call for the right source, applied at right time, at the right rate at the right placement. Producers in South Dakota ask when the correct time to apply nitrogen fertilizers. Mean annual precipitation in the major South Dakota corn growing areas ranges from 16 to 26 inches. This is a relatively dry climate compared to other major corn growing regions and the effect of nitrogen timing might not be as important. Therefore, a research question that challenge... A. Bly, S. Berg, D. Karki |
35. Nitrogen Timing and Sidedress Placement Strategies in MichiganNitrogen (N) timing and placement methods are key components to improve corn (Zea mays L.) N management. Studies were initiated in Richville and Lansing, MI in 2017 utilizing four N timing strategies including 100% N broadcast after planting (PRE); 50% N pre-plant incorporated with 50% N sidedressed (SD) at V6 (50/50); no pre-plant N with 100% N SD V6 (0/100); and 40 lbs N A-1 applied 2-in below and to the side of the seed (2x2) with remaining N SD V6. The PRE strategy was also appl... T. Purucker, K. Steinke |
36. Not All Litter is Created Equal: Differences in Nitrogen Mineralization Among Broiler Litter TypesOver three fourths of U.S. broiler chicken production is located in the Southeast and generates a substantial amount of broiler litter (BL). Broiler litter is a mixture of bedding material and manure that can be a valuable nutrient source for row crop production when properly used. New technologies provide farmers with the opportunity to use a combination of BL and inorganic fertilizers with minimal environmental impact. The first part of the project evaluated integrated N management systems ... L. Fitzgerald, E. Ritchey, J. Mcgrath, J. Shockley, H. Poffenbarger |
37. Nutrient Management and Starter Fertilizer for No-till CornNo-till corn acreage has steadily increased in Illinois. No-till presents unique problems of nutrient stratification, increased surface residue, and cool, wet soils which may influence nutrient availability. Two experiments were initiated in 1993 at 4 locations to evaluate the response of no-till corn to: 1) primary N applications of anhydrous ammonia preplant, UAN broadcast preplant, and ammonia sidedressed at V6; 2) starter fertilizers with factorial combinations of N, P, and K banded 2 inches... |
38. Nutrient Management Following CRP- Concerns and On-Going ProjectsThe future of the Conservation Reserve Program (CRP) is uncertain as this paper is being prepared, however, most agree that at some point a significant acreage currently in CRP will be brought back into production. The peak of contract expirations for the 36 million acres of CRP will occur in the fall of 1996 with the first contracts originally due to expire in 1995 (Figure 1). Many of the Northcentral states have substantial CRP acreage's making post-CRP management an important topic for this r... |
39. Performance of Grain Oats at Different Nitrogen Regimes when Grown with and without Plant Growth Regulator (PGR)Among small grains grown in the South Dakota (SD), oat is considered the most susceptible to lodging which can result to significant yield loss due to harvest difficulty. Although current South Dakota State University (updated 2005) recommends 1.3 pounds nitrate N per bushel of oats (minus soil test N and legume credit), producers have been using lesser than the SD recommended rate to avoid lodging. This study was initiated in 2016- i) to evaluate the response of oat grain yield at various ni... D. Karki, A. Bly |
40. Planting Equipment for No-tillPlanters or drills have to cut and handle the residue, penetrate the soil to desired seeding depth, and establish proper seed-to-soil contact. Keeping these three items in mind, a producer can evaluate the strengths or weaknesses of any piece of planting equipment and make any adjustments or changes necessary to make no-till planting successful. Fortunately. most currently available planters and drills can be used for no-till with few, if any, modifications. In the early days of no-till, produce... |
41. Polyhalite Alters the Uptake and Partitioning of Mineral Nutrients in MaizeModern maize (Zea mays L.) hybrids coupled with advanced agronomic practices have led to an increased yield potential on many US corn acres. To realize these higher yields demands a better understanding of crop nutrition. The objective of this study was to document the pattern of uptake, partitioning, and remobilization of nutrients released after potassium fertilization, specifically muriate of potash (MOP; 0-0-60) and/or polyhalite fertilizers (0-0-14-6Mg-17Ca- ... S. Foxhoven |
42. Preparing for No-till Planting into CRP LandAs CRP contracts expire, many producers are considering bringing the land back into crop production. In order to conserve soil and water, and to keep the soil building benefits of idling the land for ten years, no-till is the best production system to use. Tillage will destroy the soil structure that has built up from the freeze-thaw and wetting-drying cycles. In addition, it will plant surface weed seeds and stimulate seeds which have been buried for the last ten years. Tillage will also fluff ... |
43. Real-Time Soil Nitrate SensingIon-selective field effect transistors (ISFETs) have inherent features such as small dimensions. low output impedance. high signal-to-noise ratio, low sample volumes and the potential for mass production, which are required for a real time soil sensor. However, ISFETs have the disadvantage of long-term drift, which is diminished by the use of a Flow Injection Analysis (FIA) system. In fact, FIA and ISFETs are complementary since the small sample volumes and rapid response of ISFETs allow the mi... |
44. Returning Conservation Reserve Program Land to Crop Production: Weed Management ConsiderationsThe conservation reserve program (CRP) was formulated in the 1985 Food Security Act and established to help prevent soil erosion on more than one third of the crop acres in the United States (USDA, 1986). Soil erosion represents the greatest threat in agriculture to the environment. Nationally, an estimated 750,000,000 tons of soil have been conserved as a result of CRP representing an estimated annual savings of $2 billion in off-farm clearing of eroded soil. Other benefits of CRP wildlife enha... |
45. Seed Inoculations and Nitrogen Fertilizer Trials with SoybeansCurrently there is a lot of interest in soybean seed inoculation. There are some new products on the market that are creating renewed interest in seed inoculation even on fields that have a history of soybean production. Some of the new inoculants have claims for higher potency, new and better strains of Rhizobium. higher numbers of Rlzizobiurn per gram of material, sterilized peat media, seed sticker additions and etc. Many companies are beginning to pay more attention to storage and handling o... |
46. Side-dressing Nitrogen Influence on Nitrogen Release Dynamics of Early and Late-Terminated Cereal Cover CropTermination date and nitrogen application of corn (Zea mays L.) can influence the decomposition rate of cover crops in a corn cropping system. Our objective was to evaluate (i) the biomass accumulation and nutrient uptake of wheat (Triticum aestivum L.) fertilized with 34 kg N/ha and (ii) decomposition rate of wheat terminated early (4 weeks prior to planting) and late (at corn planting time) with and without side-dressing N at 168 kg N/ha. Our preliminary d... A. Sadeghpour, G. Singh, A. Weidhuner, R. Lange |
47. Site-Specific Management of N Fertilization in OntarioSignificant within field variability of soil properties, such as soil fertility, and plant growth have been well docome~ited. Standard soil testing practices and fertilizer recommendations which enco~npass an average soil test value for a field and a constant rate of fertilization will obviously result in certain areas of a field being either over or under fertilized. As indicated by Kachanoski and Fairchild (1995), for a single (constant) rate of fertilizer application, reconimendations based o... |
48. Site-Specific Management Research in MIssouri- Swamped in Spatial DataWith a maturing GPS technology, we have over the past couple of years become very enamored with producing maps on crop production fields. It wasn't long ago that the only map available was the soil map from county soil surveys. Continued sensor development and aerial photography and sensing, along with decreasing costs to store and manipulate spatial data, will mean that in the future measuring and mapping data will be the rule. There have been a lot questions raised regarding the minimum amount... |
49. Site-Specific Research in North DakotaSite specific fertilizer application is currently being practiced in the Red River Valley of North Dakota/Minnesota A study has been initiated to determine sampling practices suitable for North Dakota producers using sitespecific farming both within and west of the valley. Two forty acre fields were sampled in 1994 in a 110 ft. grid, separating each sample into 0-6" and 6-24" subsamples. Smaller grid sizes were also obtained at 10 and 2 ft. grid distances in selected areas of each field. Nitrate... |
50. Soil Nitrogen Management is Impacted by Soil Texture and WeatherNitrogen (N) is an important nutrient for corn production that is often supplied as inorganic fertilizer, but its use can also lead to environmental degradation. The 4R (right rate, source, time, and placement) approach has been suggested as a framework for N management to improve crop yield and nutrient use efficiency while minimizing environmental contamination. There is not a universal 4R best management strategy, nor should there be because many variables impact N... J. Spackman |
51. Soil Phosphorus Fractions and Legacy after Long-term Fertilizer Placement in a Corn-Soybean RotationPhosphorus (P) fertilizer placement can affect plant P uptake during the growing season, however, the long-term interaction of placement and plant root P uptake can also affect soil P pools. The objective of this study was to evaluate the influence of long-term P fertilizer placement on soil P pools (labile, moderately labile and non-labile) and legacy soil P accumulation under a corn (Zea mays) -soybean (Glycine max (L.) Merr.) rotation. A field study was conducted for ten years from 20... M. Coelho, D. Ruiz diaz, G. Hettiarachchi, F. Hansel |
52. Soil Properties and Corn Yield as Effected by 70 year of Cattle Manure ApplicationLong-term experiments provide valuable information about the environment x agronomy interaction impacts on soil and crop productivity. The irrigated Knorr-Holden experimental site near Mitchell, Nebraska was established in 1912 and had a non- replicated unfertilized maize plot until 1941. In 1942 the plot was split into two manure treatments (0 and 27 Mg ha-1 yr-1 cattle manure) with 0.04 ha each. In 1953, second replication was added using adjacent land. The same year, manure treat... B. Maharjan |
53. Soybean Response to Potassium Fertility and Fertilizer in ManitobaSoybean acres have increased greatly in Manitoba in recent years, now occupying more than 25% of the province’s annual crop land. Potassium removal by soybean is greater than any other crop grown in Manitoba (1.1 – 1.4 lb K2O/bu). This large removal, accompanied by the large and rapid expansion in soybean acres, has contributed to an increase in province-wide potassium removal rates and likely explains the increase in incidence of potassium deficiency symptoms reported in recent y... M. Bourns, D. Flaten, J. Heard, G. Bartley |
54. Starter Fertilizer Interactions with Corn HybridsThe objective of this study was to evaluate the response of corn hybrids grown in a dryland, no-tillage production system on a soil high in available phosphorus to starter fertilizer. Treatments were corn hybrids (5 in 1993 and 6 in 1994) grown with or without starter fertilizer. Starter fertilizer (30 Ib N and 30 Ib P,O,) was applied 2 inches to the side and 2 inches below the seed at planting. Nitrogen was balanced on all plots to give a total of 180 IbIA. Bray-I P level in the experimental ar... |
55. Sulfur Fertility for Kentucky Agriculture: An UpdateSulfur (S) is an essential secondary nutrient for plant growth and is involved with the synthesis of chlorophyll, hormones, and a structural component of proteins. The need for supplemental S fertilizer in Kentucky has been questioned for many years due to lower atmospheric S deposition, fewer fertilizer impurities, soil test laboratory recommendations, and greater crop yields, but field research has not supported this concern. Recent tissue surveys in wheat and alfalfa across ... E. Ritchey, J. Gray |
56. The Conservation Reserve Program- Changes on the HorizonTen years ago, Congress passed the foundation of current conservation programs--the Food Security Act of 1985. Today, one program in particular, has exceeded many peoples' expectations. The Conservation Reserve Program (CRP) yas designed to take 40 - 45 million acres of highly erodible cropland out of production for a 10 - 15 year period. As the first CRP contracts begin to expire, Congress and the Administration are grappling with the program's future in the context of the 1995 farm bill. Will ... |
57. Trapping Function of Grassed FiltersThe potential to contaminate rivers, streams, and other natural water bodies with sediment, nutrients, pesticides and bacteria in runoff from agricultural land is a very important water quality issue. Conservation tillage has proven to be effective in decreasing soil exposure to rainfall, thus decreasing water runoff and erosion potential. Vegetative filters slow down runoff that allows sediment, nutrients, pesticides and bacteria to be deposited. Combining conservation tillage with vegetative f... |
58. Use and Misuse of Aerial ImageryThroughout the 1990’s agricultural researchers were hitting the sky’s collecting untold amounts of spectral data. The majority of that push quieted down in the early 2000’s as scalability was a constant struggle. However, in the past few years the introduction of affordable and easy to use unmanned aerial vehicles (UAV), more cost effective cameras, and significant increase in satellite constellations has reignited the interest in remote sensing that died out a dec... B. Arnall |
59. Using High-Tech Media Tools to Transfer the Principals of System Research to FarmersBeginning in 1981, research and extension personnel at Virginia Tech and the University of Maryland formed Intensive Wheat Management Teams. Over the next six years these Teams developed a higher yielding, more profitable and environmentally superior soft red winter wheat production system. Yields greater than 100 bu/a were achieved every year. This was at a time when average wheat yields were in the 40 bu/a range (Table 1). Intensive wheat research continues today to refine and update the syste... |
60. What Grid Cell Size is Best for P and K Soil Testing in MinnesotaA study to evaluate the best grid cell size and best soil san~ple system for immobile nutrients was conducted in South-Central Minnesota from 1993 to 1995. A corn/soybean cropping system was used. The soils at the research sites were formed in glacial till. Three grid cell sizes, 60 x 60 ft., 180 x 180 ft., and 300 x 300 ft. were evaluated. The sampling patterns included a mid-plot sample, a 60 x 60 ft. grid all-point pattern. and five to nine sample pattern. The smaller the grid cell the better... |