Proceedings
Authors
| Filter results3 paper(s) found. |
|---|
1. 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 H3A... A. Mallarino, J. Jones |
2. Influence of Source and Particle Size on Agricultural Limestone Efficiency at Increasing Soil pHExcessive soil acidity is known to have potential negative impacts on crop production. The chemical and physical characteristics of a liming material determine its capacity to neutralize soil acidity. The calcium carbonate (CaCO3) equivalent (CCE) and estimates of particle size impact on the efficiency at increase soil pH are considered when assessing a material’s liming value. The reaction of limestone particles within the soil depends largely on the soil pH and the material surface area... J. Jones, A. Mallarino |
3. Managing Phosphorus and Potassium Soil Test Levels and Effects on Corn Response to Nitrogen with Variable Crop PricesAnnual fertilizer investment for corn-soybean rotation systems represent a significant portion of annual input costs. Variable crop and fertilizer prices raise questions of which macronutrients can be prioritized or cut from fertilization programs. Corn yield response to N fertilization is affected by soil N supply, crop N demand, and interacting factors that affect crop N use, such as phosphorus (P) and potassium (K) supply. The later also influencing soybean yield in the rotation. To investigate... J. Jones |