Proceedings
Authors
| Filter results12 paper(s) found. |
|---|
1. Prediction of Corn and Soybean Grain Yield Response to P in Minnesota Using the Haney H3A and Mehlich-III TestsMinnesota soils are highly variable in P availability due to the wide range of chemical properties. Currently, two soil tests are used to measure soil P in Minnesota, the Bray-P1 for pH<7.4 and the Olsen P for pH>7.4. The purpose of this study was to correlate crop response in corn and soybean rotations to the Bray-P1, Olsen, Mehlich-III, and Haney H3A extractions and to determine critical concentrations for each extraction method. Soil P tests were also correlated with one another to determine... D. Kaiser, L. Leverich, J. Vetsch, J. Strock |
2. Optimizing P Based In-Furrow Starter Fertilizer in Fields with Variable Soil Test P LevelsSoils in Minnesota are highly variable in chemical properties, particularly pH which can range from acidic to basic within a single field. In-furrow starter fertilizer is popular if fields with variable- and high (>7.5) pH fields to enhance early plant growth. The purpose of this study was to determine if in-furrow starter fertilizer rate should be varied in fields with varying pH and if starter fertilizer can increase yield in the presence of broadcast P applied at a non- limiting rate. Eight field... |
3. Residual Effects of P Fertiliration Lessons for the EightiesSeveral states in the North Central Region have established long-term phosphorus studies. These experiments were designed to evaluate the residual effects of P fertilizer and also generate P soil test calibration data in a situation where a range of soil test levels exist on one soil. These data are extremely useful for evaluating year-to-year fluctuations in crop response to soil test P and establishing response probabilities at a given soil test level. Valuable lessons can also be learned from... |
4. Role of Land Tenure-Other Factors in Soil P InterpretationsSoil test interpretation should recognize the residual value of applied PI the inherent limitations of soil P tests, and utilize an approach that can be easily personalized at the local level. These criteria were used to develop an interpretation approach utilizing a computer spreadsheet to estimate the optimum soil test level for an individual grower. The spreadsheet requires the following inputs: a calibration curve, acceptable marginal return, interest rate, land tenure, soil test buffer potential,... |
5. The State of the Art StartersInterest in reduced tillage has caused a resurgence in the use of starter fertilizer. Starter fertilizer research has been conducted on many crops across the country. The purpose of this paper is to highlight recent research on a variety of crops including corn. cotton, sorghum, soybean, canola, sugar beet, and potato. Increased yields from starter fertilizers are common in low P soils and several factors may lead to increased yields even when soil P and K levels are high. Geographic trends in yield... |
6. 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 region... |
7. Use of Yield Goals for Providing N Rate Suggestions- General ConceptsRecent studies in the North Central region have shown a poor relationshp between optimum yield of individual sites and optimum fertilizer N rate (Sawyer et al., 2006). The outcome has been the development of fertilizer recommendation approaches that do not consider site yield goal (Vanotti and Bundy, 1994a; Sawyer and Nafiiger, 2005). This causes one to ponder how so many recommendation programs utilizing yield goal were developed in the fist place and have continued in use for more than 40 years.... |
8. Continuous Corn Production As Affected By Starter Fertilizers Containing Nitrogen, Phosphorus, and SulfurCrop rotations in the Midwest have changed from the traditional corn-soybean rotation to more corn-intensive rotations. Due to the expanding demand for corn to supply the ethanol industry and the increasing insect and disease challenges facing soybean producers, some farmers are switching to a corn-corn-soybean rotation or for some, continuous corn. These rotations produce large amounts of biomass (corn stover) that often remain on the soil surface with present day tillage systems. This is good... |
9. Re-Evaluating Rate, Time, and Placement of Urea and Other Nitrogen Sources in MinnesotaUrea is increasingly an important nitrogen (N) source in Minnesota. Approximately 43% of our farmers use urea as their major N source. In the southwestern, south-central and west-central areas approximately 45% of the N is applied in the fall, 50% is applied in the spring, and 5% is applied at sidedress. While most of those that use urea as the major N source apply it in the spring, approximately 4% do the major application with urea in the fall and there are others that apply some of their N... F. Fernandez, K. Fabrizzi, J. Vetsch, D. Kaiser |
10. 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 samples... J. Vetsch, D. Kaiser |
11. Can ProveN Reduce Corn Nitrogen Requirement in Minnesota?ProveN is a microbial product applied in-furrow with the goal of reducing the total amount of nitrogen fertilizer needed for corn (Zea mays L.). Six field trials were established over three growing seasons in Minnesota to evaluate corn response to nitrogen with and without ProveN applied at planting on the seed. Nitrogen was applied as urea prior to planting at five locations and split applied with 1/3 of the total rates of nitrogen applied at -planting, at V4, and V8 growth stages. ProveN... D. Kaiser, J. Vetsch, M. Currie |
12. How Do Cover Crops, Nitrogen Rate and Cropping System Affect Nitrate Loss in Tile Drainage Water?A field research study was conducted on clay loam soil in Waseca Minnesota. The objectives were to quantify the effects and interactions of cover crops, nitrogen (N) fertilizer rates and cropping system on corn production and nitrate-N concentration and loss in tile drainage water. Cover crop treatments [cereal rye and a blend of annuals (oat, forage pea and radish)] were drilled soon after corn silage harvest each fall. Nitrogen treatments were split-applied at planting and V3 growth stage. Corn... J. Vetsch, A. Cates |