Potential Exam Questions IV

Warning: The following questions may be poorly worded and subjective. Exam questions will be worded differently. Exams may also contain questions not listed here.

  1. Identify the 3 general forms in which Phosphorous (P) is found in the soil.
  2. In general, how much P is found in the soils of the coastal plains?
  3. Which available P molecule is more likely to be found in an acidic soil? Basic?
  4. By which type of movement of the soil solution is most P absorbed by plants?
  5. What is considered to be live Organic matter (OM)?
  6. Illustrate the connection of organic forms of P between the soil soln., microbes and stable OM.
  7. What causes (facilitates) the organic transformations of P between the OM, Soil Solution and Microoranisms?
  8. What can happen to the available P in the soil solution if there is too much fertilizer added to the soil?
  9. What precisely is meant by 'available' vs 'unavailable' P (or K)
  10. Name 2 soil processes that would cause inorganic P in soil soln. to become unavailable?
  11. Identify 4-5 factors which determine the retention/availability of P in soils
  12. In what pH range is P at max availability?
  13. Why do cations have an affect on P?


  14. Should answer a question similar to: How many pounds of pure P is in an 80 pd. Bag of 10-10-10 fertilizer?
  15. Name 2 P fertilizers and their P%.
  16. Why would the addition of specific bacteria to the soil increase available P?
  17. Name a couple of fertilizer qualities that affect the fate of fertilizer P
  18. In general, what will happen to P that has been Broadcast in terms of fixation into an unavailable form?
  19. Under what scenario would it be preferable to apply banded P fertilizer? Broadcast?


  20. In which soil texture classes are K more likely to be found?
  21. Identify the 4 general sources of soil K.
    1. Which contains the most total K?
  22. Indicate the approximate amount of K taken up by plants through diffusion vs. mass flow (%).
  23. When the K is removed from the soil soln. by plants, how is it replenished?
  24. Where is the solid exchangeable K located in the soil?
  25. Where is the Non-exchangeable K located?
  26. What is the difference between exchangeable and non-exchangeable K in terms of availability?
  27. What is meant by "unavailable" K?
  28. Describe K 'Fixation'.

  29. Identify at least 4 factors associated with the soil particles (physical/chemical/etc) which affect K retention/availability.
  30. Identify at least 2 factors associated with the climate which affect K retention/availability.
  31. In what 2 ways do Ca and Mg compete with K?
  32. Should answer a question similar to: How much pure K is in an 80 pd. Bag of 10-10-10 fertilizer?
  33. Name 2 K fertilizers and indicate the amount of K in them
  34. Under what 3 soil conditions would it preferable to band K fertilizer?
  35. Where exactly should a fertilizer band be located with respect to the seed?


  36. Name 2 sources from which Ca is Slowly available.
  37. Does available Ca revert to a slowly available or unavailable form?
  38. Describe or illustrate the 4 possible fates of Ca once it enters the soil soln.
  39. Name 4 factors which influence Ca retention /Availability in the soil
  40. What type of fertilizers are formulated specifically to provide Ca? Trick question
  41. How should Ca be applied, Broadcast or banded? WHY?


  42. What soil/climatic conditions lead to low Mg concentrations in the soil?
  43. Name one source of slowly available Mg
  44. Does available Mg revert to a slowly available or unavailable form?
  45. Name 4- 5 factors which influence Mg retention /availability in the soil
  46. Why do cations affect retention /availability of Mg (and K, Ca, Fe, etc)?
  47. Name 1 Mg fertilizer and its %Mg
  48. Identify 6 possible forms of Sulfur
  49. Name 3-4 factors which influence S retention /Availability in the soil
  50. Name 2 S fertilizers and their % S
  51. What effect does sulfur have on soil pH?


  52. Name the 7 micronutrients?
  53. In what form are each absorbed by plants?
  54. Which are NOT metals?
  55. Draw or describe the relationship between the primary minerals, clay minerals, clay particles and organic matter with the soil solution.
  56. What are chelates?
  57. Why are they important for micronutrient uptake? (2 reasons)
  58. Name 4 factors which influence their retention /Availability in the soil
  59. In what pH range is each most available?
  60. Name one fertilizer for each (aside from chelates)
  61. Why are micronutrients often found in high quantities in ag/turf soils?