CFB Soil Science & Amendments 3

Question 1

Which soil test is used to determine the lime requirement for a sports field?

Accepted Answer

Buffer pH test (e.g., SMP buffer test)

Answer

A buffer pH test measures the soil's resistance to pH change and is used to calculate the exact lime rate needed to reach the target pH efficiently.

Question 2

In the USGA construction method, what is the primary function of the gravel layer placed beneath the sand root zone?

Accepted Answer

To create a perched water table that improves moisture retention in the sand above

Answer

The gravel layer creates a textural discontinuity that suspends water in the overlying sand root zone (a perched water table), improving moisture and nutrient retention while still allowing excess drainage.

Question 3

In soil science, 'permeability' refers to:

Accepted Answer

The ease with which water or air moves through the soil

Answer

Soil permeability describes how readily fluids and gases flow through the pore network, which directly governs drainage performance of a sports field.

Question 4

Gypsum (calcium sulfate) is most commonly applied to sports field soils to:

Accepted Answer

Improve clay structure by supplying calcium without significantly changing pH

Answer

Gypsum provides calcium that displaces sodium and helps aggregate clay particles, improving structure, drainage, and aeration without altering soil pH.

Question 5

What is the primary agronomic benefit of a regular topdressing program on a natural grass sports field?

Accepted Answer

Gradual modification of the root zone profile and smoothing of the surface

Answer

Topdressing applies thin, repeated layers of sand or soil mix that dilute thatch, smooth surface irregularities, and gradually improve root zone drainage and firmness.

(CFB) Certified Field Builder Practice Test

(CFB) Certified Field Builder Practice Test

CFB Soil Science & Amendments 3