Practice Test Geeks(CCA) Certified Crop Advisor Practice Test
← All CCA Flashcard Decks

Nutrient Management Flashcards

7 cards from real CCA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Nutrient Management flashcards as text

  1. Cation exchange capacity (CEC) is primarily influenced by soil texture and organic matter because both contribute:

    Answer: Negatively charged exchange sites

    Clay minerals and organic matter carry net negative surface charges that attract and hold cations such as Ca²⁺, K⁺, and NH₄⁺.

  2. Which of the following best describes the role of mycorrhizal fungi in plant phosphorus nutrition?

    Answer: They extend the effective root absorptive surface area to access P beyond the depletion zone

    Mycorrhizal hyphae extend well beyond the P depletion zone around roots, dramatically increasing the soil volume from which P can be absorbed.

  3. A soil test report shows 85% base saturation for calcium, 5% for magnesium, and 3% for potassium. The calcium:magnesium ratio is approximately:

    Answer: 17:1

    Ca:Mg ratio = 85 ÷ 5 = 17:1, which is above the commonly cited 'ideal' range of 6:1 to 10:1, suggesting possible Mg tightness.

  4. Which macronutrient is most prone to leaching below the root zone in coarse-textured, high-rainfall soils?

    Answer: Nitrate-nitrogen

    Nitrate (NO₃⁻) carries a negative charge and is repelled by negatively charged soil particles, making it highly mobile and susceptible to leaching.

  5. Tissue testing at the V6 growth stage of corn most accurately reflects nutrient status when the sample consists of:

    Answer: The uppermost fully collared leaf

    For V6 corn, the uppermost fully developed (collared) leaf is the standard tissue sample, as it reflects current nutrient supply to actively growing tissue.

  6. Potassium fixation (non-exchangeable K retention) is most pronounced in soils containing high amounts of:

    Answer: 2:1 expanding clay minerals such as vermiculite and illite

    2:1 expanding lattice clays have interlayer sites that can trap K⁺ ions, removing them from the exchangeable pool and reducing plant availability.

  7. When applying variable-rate fertilizer using a management zone approach, zones are typically delineated using which data layers?

    Answer: Yield maps, soil EC data, and soil sampling results

    Management zones are commonly created by combining historical yield data, apparent soil electrical conductivity (EC), and grid or zone soil sampling to capture spatial variability.