Kentucky CCA Study Guide Questions and Answers with
Complete Solutions 100% Correct 2024.
If a tobacco field is diagnosed with manganese toxicity symptoms, the best thing a farmer can do is:
be sure to correct the soil pH before planting his tobacco next year
Which of the following crops would be most likely to respond to potassium applications? a) tobacco b)
soybean c) corn d) alfalfa
alfalfa
How does CEC influence plant availability of a nutrient present in the soil solution as a cation?
As CEC increases, plant availability improved
A soil has poor P availability. How will this affect the observed response to added nitrogen fertilizers?
Nitrogen response will be limited by the inadequate P supplies
In scientific language, cation exchange capacity (CEC) is expressed in milliequivalents/100 g soil. If a
farmer's soil test says that her soil has 142 ppm of potassium, how many pounds/acre of potassium
does her soil have?
284 pounds/acre
For no-till corn, why is a slightly higher rate of N fertilizer recommended?
because N losses to immobilization and denitrification are higher in no-till systems
Which element can be taken up by plants as either an anion or a cation?
nitrogen
The form in which nitrogen exists at the start of its mineralization process is:
as part of soil organic matter
Which of the following elements is NOT essential for plant growth? a) copper b) iron c) molybdenum
d) silicon e) potassium.
silicon
At which stage should you take samples for plant analysis of corn?
one-half of plants beginning to silk
Aluminum toxicity is most likely to be a problem when:
soil pH is very low
For which agricultural chemical phase would layers of clothing be advised? a) liquid b) solid c) gas d) all
three phases require this protection.
,b) solid
Potassium can be fixed on soil clays in three different positions: edge, internal, and para. Which
position is most likely to be released to soil solution?
para
Which type of clay mineral would have the highest P retention? a) amorphous clays b) oxides c) 1:1
clays d) 2:1 clays.
amorphous clays
You see tobacco plants that are dark green, severely stunted, and have yellow flecks in lower leaves.
What is the likely culprit?
inadequate soil phosphorus
Which of the following nitrogen forms would cause the largest drop in soil pH? a) anhydrous ammonia
b) ammonium nitrate c) ammonium sulfate d) calcium nitrate
anhydrous ammonia
What factors cause ammonium in the soil to be mineralized to nitrate?
A pair of soil bacteria is responsible for this reaction
The scenario under which banded starter fertilizer is most likely to benefit corn is:
no-till, early planted, low soil test
The most common uptake form of potassium is as
K+
What is the main reason for doing plant analysis?
to accurately diagnose nutrient deficiencies.
Which of the following statements are true about sulfur in Kentucky soils?
Our soils receive about 10 to 15 pounds/acre of S in rainfall every year
What potassium form must tobacco growers avoid?
potassium chloride
If you are deciding how much P and K to apply to winter wheat, and you plan to double crop soybean
the following summer, how should you decide how much P and K to apply?
Use the P recommendation for wheat, but use the K recommendation for soybean.
How does soil pH affect P availability?
P is most available to plants at a pH of about 6.5.
, The bad thing about using urea as a nitrogen source for no-till corn is
it is subject to significant losses through the process of volatilization.
What is the key advantage of anhydrous ammonia over other forms of nitrogen?
Since it has the highest analysis, it is often the least costly form of nitrogen
Of the three macronutrients, which is most mobile within crop plants?
nitrogen
How many tons of ammonium nitrate (34-0-0) would be required to deliver 300 pounds of N per acre
to 40 acres of tobacco?
17.6
Besides C, H, and O, which of the following are essential elements required in the largest amounts?
nitrogen, phosphorus, and potassium
If you are getting a soil sample for a soil test, how deep should you take your samples?
6 inches
Soil solution levels of calcium are dependent on
soil pH, how much clay is present in the soil, what type of clay is present in the soil
Roles of potassium in plants include:
an important factor in helping balance negative charges in transported nutrients
A fertilizer with an analysis of 0-46-0 would be
triple superphosphate
If you are concerned about a deficiency of a relatively immobile plant nutrient, in what part of the
plant should you look first?
newly emerging leaves and buds
Nitrogen use efficiency by cereal crops is
reduced if N application rates are excessive, reduced if soils are consistently water-logged, reduced if
other nutrients are in short supply
If your corn was nitrogen deficient, what symptoms should you be able to see?
yellowing of lower leaves
Keeping pH up close to 7.0 so that molybdenum is reasonably available is most important for which
plant?
alfalfa
Complete Solutions 100% Correct 2024.
If a tobacco field is diagnosed with manganese toxicity symptoms, the best thing a farmer can do is:
be sure to correct the soil pH before planting his tobacco next year
Which of the following crops would be most likely to respond to potassium applications? a) tobacco b)
soybean c) corn d) alfalfa
alfalfa
How does CEC influence plant availability of a nutrient present in the soil solution as a cation?
As CEC increases, plant availability improved
A soil has poor P availability. How will this affect the observed response to added nitrogen fertilizers?
Nitrogen response will be limited by the inadequate P supplies
In scientific language, cation exchange capacity (CEC) is expressed in milliequivalents/100 g soil. If a
farmer's soil test says that her soil has 142 ppm of potassium, how many pounds/acre of potassium
does her soil have?
284 pounds/acre
For no-till corn, why is a slightly higher rate of N fertilizer recommended?
because N losses to immobilization and denitrification are higher in no-till systems
Which element can be taken up by plants as either an anion or a cation?
nitrogen
The form in which nitrogen exists at the start of its mineralization process is:
as part of soil organic matter
Which of the following elements is NOT essential for plant growth? a) copper b) iron c) molybdenum
d) silicon e) potassium.
silicon
At which stage should you take samples for plant analysis of corn?
one-half of plants beginning to silk
Aluminum toxicity is most likely to be a problem when:
soil pH is very low
For which agricultural chemical phase would layers of clothing be advised? a) liquid b) solid c) gas d) all
three phases require this protection.
,b) solid
Potassium can be fixed on soil clays in three different positions: edge, internal, and para. Which
position is most likely to be released to soil solution?
para
Which type of clay mineral would have the highest P retention? a) amorphous clays b) oxides c) 1:1
clays d) 2:1 clays.
amorphous clays
You see tobacco plants that are dark green, severely stunted, and have yellow flecks in lower leaves.
What is the likely culprit?
inadequate soil phosphorus
Which of the following nitrogen forms would cause the largest drop in soil pH? a) anhydrous ammonia
b) ammonium nitrate c) ammonium sulfate d) calcium nitrate
anhydrous ammonia
What factors cause ammonium in the soil to be mineralized to nitrate?
A pair of soil bacteria is responsible for this reaction
The scenario under which banded starter fertilizer is most likely to benefit corn is:
no-till, early planted, low soil test
The most common uptake form of potassium is as
K+
What is the main reason for doing plant analysis?
to accurately diagnose nutrient deficiencies.
Which of the following statements are true about sulfur in Kentucky soils?
Our soils receive about 10 to 15 pounds/acre of S in rainfall every year
What potassium form must tobacco growers avoid?
potassium chloride
If you are deciding how much P and K to apply to winter wheat, and you plan to double crop soybean
the following summer, how should you decide how much P and K to apply?
Use the P recommendation for wheat, but use the K recommendation for soybean.
How does soil pH affect P availability?
P is most available to plants at a pH of about 6.5.
, The bad thing about using urea as a nitrogen source for no-till corn is
it is subject to significant losses through the process of volatilization.
What is the key advantage of anhydrous ammonia over other forms of nitrogen?
Since it has the highest analysis, it is often the least costly form of nitrogen
Of the three macronutrients, which is most mobile within crop plants?
nitrogen
How many tons of ammonium nitrate (34-0-0) would be required to deliver 300 pounds of N per acre
to 40 acres of tobacco?
17.6
Besides C, H, and O, which of the following are essential elements required in the largest amounts?
nitrogen, phosphorus, and potassium
If you are getting a soil sample for a soil test, how deep should you take your samples?
6 inches
Soil solution levels of calcium are dependent on
soil pH, how much clay is present in the soil, what type of clay is present in the soil
Roles of potassium in plants include:
an important factor in helping balance negative charges in transported nutrients
A fertilizer with an analysis of 0-46-0 would be
triple superphosphate
If you are concerned about a deficiency of a relatively immobile plant nutrient, in what part of the
plant should you look first?
newly emerging leaves and buds
Nitrogen use efficiency by cereal crops is
reduced if N application rates are excessive, reduced if soils are consistently water-logged, reduced if
other nutrients are in short supply
If your corn was nitrogen deficient, what symptoms should you be able to see?
yellowing of lower leaves
Keeping pH up close to 7.0 so that molybdenum is reasonably available is most important for which
plant?
alfalfa
