Lesson 1Soil organic matter: functions, mineralization rates, an' management implicationsExplore soil organic matter as a reservoir of nutrients, water, an' biological activity. Discuss mineralization rates, environmental drivers, an' management practices dat build or protect organic matter in Midwest systems.
Organic matter contributions to CEC and waterNitrogen and sulfur mineralization processesTemperature and moisture effects on releaseResidue management and cover crop impactsTillage intensity and long-term SOM trendsLesson 2Common fertilizer sources, nutrient forms, an' conversion to elemental N, P2O5, K2O (e.g., urea, ammonium nitrate, MAP, DAP, potash, sulfate, chelates)Reviews common fertilizer materials used in Midwest corn, including nitrogen, phosphorus, potassium, sulfur, an' chelated micronutrients. Emphasizes nutrient forms, analysis, an' converting product rates to elemental nutrients.
Typical N, P, K, and S fertilizer productsAmmonium, nitrate, and urea behavior in soilConverting analysis to lb nutrient per acreMAP, DAP, and potash handling and placementChelated micronutrients and compatibility issuesLesson 3Corn macronutrient uptake patterns an' timing (N, P, K) by growth stageDescribes how corn uptake of nitrogen, phosphorus, an' potassium changes by growth stage. Connects uptake curves to sidedress timing, starter fertilizer value, an' strategies to reduce loss while meeting peak crop demand.
Early-season nutrient needs and starter useRapid uptake during V6 to tasseling stagesLate-season nutrient demand and remobilizationAligning N timing with crop demand curvesSynchronizing P and K supply with root growthLesson 4Secondary nutrients an' micronutrients relevant to corn (S, Mg, Zn, B, Mn): roles an' critical sufficiency rangesDetails di roles of sulfur, magnesium, zinc, boron, an' manganese in corn physiology. Reviews deficiency symptoms, soil an' tissue critical levels, an' when supplemental applications are justified in Midwest production systems.
Physiological roles of S, Mg, Zn, B, and MnSoil and tissue critical levels for each nutrientVisual deficiency symptoms by growth stageSoil and foliar sources for secondary nutrientsWhen micronutrient fertilization pays in cornLesson 5Interpreting soil test reports: units (Bray/P, Mehlich-3, Olsen), extractant differences, an' common lab recommendationsCovers how to read Midwest soil test reports, focusing on units, extraction methods, an' calibration. Learners compare Bray, Mehlich-3, an' Olsen P tests an' translate lab results into clear, field-ready fertilizer decisions.
Common soil test units and conversionsBray, Mehlich-3, and Olsen P comparisonsInterpreting P and K calibration categoriesUnderstanding lab fertilizer recommendationsSampling depth, timing, and lab quality controlLesson 6Recommended soil test ranges fi Midwest corn fi pH, organic matter, Bray/Mehlich-3 P, exchangeable K, an' micronutrientsSummarizes recommended soil test ranges fi Midwest corn, including pH, organic matter, phosphorus, potassium, an' key micronutrients. Links categories to expected yield response an' fine-tunes fertilizer strategies.
Optimal pH and organic matter benchmarksBray and Mehlich-3 P target categoriesExchangeable K ranges by soil CEC classMicronutrient guideline levels for cornAdjusting targets for yield and rotationLesson 7Typical Midwest yield targets an' corresponding nutrient removal rates (bushels/acre to lb nutrient/acre conversions)Links typical Midwest corn yield goals to nutrient removal in grain an' stover. Teaches bushel-to-pound conversions, removal coefficients, an' how to use dem to design replacement an' build-up fertilizer programs.
Nutrient content of corn grain and stoverBushel-to-pound nutrient removal factorsEstimating field-level nutrient exportsBalancing removal with fertilizer inputsPlanning build-up versus maintenance ratesLesson 8Soil texture, structure, an' water-holding capacity: implications fi nutrient retention an' leaching riskExplores how soil texture an' structure influence water storage, aeration, an' root growth in Midwest fields. Links dese properties to nutrient retention, leaching risk, an' management practices dat protect yield an' water quality.
Classifying Midwest soil textures in the fieldStructure types and their impact on root growthAvailable water capacity and measurement methodsTexture effects on cation exchange and leachingTillage and compaction impacts on structureLesson 9Soil pH effects on nutrient availability an' liming guidelinesExplains how soil pH controls nutrient availability, aluminum toxicity, an' microbial activity. Provides liming guidelines fi Midwest soils, including lime quality, rates, an' placement to achieve target pH fi corn rotations.
pH effects on macro and micronutrient solubilityAluminum and manganese toxicity thresholdsTarget pH ranges for corn and rotationsCalculating lime rates from buffer pH testsLime sources, fineness, and application timing
