The great majority of nitrogen (95 to 98) in soils can be found in the form of ________.

The great majority of nitrogen (95 to 98) in soils can be found in the form of ________.
 
  A) dissolved anions
  B) secondary minerals
  C) dissolved cations
  D) organic compounds
  E) primary minerals

Question 2

Plants obtain nitrogen from the soil by taking up ________.
 
  A) soluble cations
  B) soluble anions
  C) soluble organic compounds
  D) all of the above
  E) none of the above

Question 3

Which of the following correctly describes the relationship among the several methods available to measure electrical conductivity (EC) of soils?
 
  A) The saturation extract procedure is more accurate than the saturated paste method.
  B) The saturated paste method takes more time than the four electrode field sensor.
  C) The four electrode field sensor gives EC values about 2x those of the saturated paste method.
  D) The saturated paste extract method is the best field method.
  E) Electromagnetic induction method requires prongs to penetrate the soil.

Question 4

Applied to agricultural crops, the term lodging refers to ________.
 
  A) plants falling over, often as a result of too much N
  B) plants losing their leaves because of a N imbalance
  C) short, stubby plants starving for N or S
  D) infestation with a high number of insect larvae lodged in the fruits or seeds
  E) pre-mature fruit drop as a result of N deficiency