14 Questions for Exam 3 - Soil Fertility Management | SOCR 350, Exams of Soil Mechanics and Foundations

Download 14 Questions for Exam 3 - Soil Fertility Management | SOCR 350 and more Exams Soil Mechanics and Foundations in PDF only on Docsity! Name: _________________________ SC 350 - Soil Fertility Management Exam #3 December 4, 2006 1. (8) Below is a list of some of the micronutrients required by plants. Place an X in the blank that explains the impact of soil pH on their availability to plants. (Circle the micronutrients that are commonly deficient in Colorado soils). Increase in availability as soil Decrease in availability as soil pH becomes more alkaline pH becomes more alkaline Zn _____________________ _____________________ Mn _____________________ _____________________ Mo _____________________ _____________________ Cu _____________________ _____________________ B _____________________ _____________________ Fe _____________________ _____________________ 2. (6) Why does soil organic matter affect micronutrient availability? 3. (9) The universally accepted micronutrient extractant is DTPA. It actually contains three components (chemicals). Describe the function of each of these components during the extracting process: DTPA: CaCl2: TEA: 4. (7) If a soil is deficient in Zn, we give a recommendation of 10 lb Zn/A. The recommendation for agronomic crops is the foliar application of a FeSO4 solution. However, the recommendation for turfgrass is a broadcast application of granular FeSO4. Why do these two application recommendations differ? 5. (6) List the 4 forms of soil potassium. Which form is directly available for plant uptake? 6. (8) a) What happens to potassium as Mica weathers into Vermiculite? b) How is the CEC of these minerals affected by this process? Explain. 7. (5) To determine the amount of K in K2O we multiply the amount of K2O by 0.83. Why? Where does this 0.83 come from? 8. (8) We us the DTPA extractant to analyze for Zn, Fe, Cu, etc. and hot water extractant to analyze for Mo and B. Explain why.