CCA Nutrient Management Planning 2

Question 1

A soil test reports 45 ppm Bray P1 phosphorus. Using the Mehlich-3 extraction, what conversion factor is typically applied to compare results between the two methods?

Accepted Answer

Multiply Bray P1 by 1.1 to estimate Mehlich-3

Answer

Mehlich-3 P values are typically about 10% higher than Bray P1, so multiplying Bray P1 by approximately 1.1 gives a rough Mehlich-3 equivalent.

Question 2

Which of the following best describes the 'credit' given to legume nitrogen in a nutrient management plan when a non-legume crop follows in rotation?

Accepted Answer

A portion of legume-fixed N is credited based on legume stand quality and yield

Answer

Previous crop N credits are based on legume stand quality, yield, and decomposition rates, typically ranging from 40–200 lbs N/ac depending on crop type.

Question 3

A CCA is developing a nutrient management plan for a field with a CEC of 8 meq/100g. Which micronutrient deficiency is MOST likely to occur in this sandy, low-CEC soil?

Accepted Answer

Zinc

Answer

Zinc deficiency is most common in coarse-textured, low-organic-matter soils with low CEC, especially in the upper Midwest and Pacific Northwest.

Question 4

Under the 4R nutrient stewardship framework, 'Right Source' refers to:

Accepted Answer

Matching the fertilizer form and grade to crop and soil needs

Answer

Right Source means selecting the correct fertilizer product—form, grade, and nutrient ratio—that matches crop requirements and soil conditions.

Question 5

When calculating a phosphorus application rate using the sufficiency approach, the primary goal is to:

Accepted Answer

Apply P to achieve a specific soil test level considered adequate for maximum yield

Answer

The sufficiency approach targets maintaining soil test P at a level sufficient for maximum economic yield rather than building reserves above that threshold.

(CCA) Certified Crop Advisor Practice Test

(CCA) Certified Crop Advisor Practice Test

CCA Nutrient Management Planning 2