CIT Soil Science and Plant Water Requirements 2

Question 1

The effective root depth of cool-season turfgrass used for irrigation scheduling is typically:

Accepted Answer

4 to 6 inches

Answer

Cool-season turfgrasses such as Kentucky bluegrass and tall fescue have active root zones of approximately 4 to 6 inches under typical managed conditions.

Question 2

If the reference ET is 0.25 inches/day and the crop coefficient (Kc) is 0.8, the crop water requirement is:

Accepted Answer

0.20 inches/day

Answer

Crop ET equals reference ET multiplied by the crop coefficient: 0.25 × 0.8 = 0.20 inches per day.

Question 3

A Management Allowable Depletion (MAD) of 50% means irrigation should be triggered when:

Accepted Answer

50% of plant available water has been consumed

Answer

MAD of 50% means you irrigate when half of the plant available water — the range between field capacity and wilting point — has been depleted.

Question 4

Which soil moisture sensor type measures moisture by analyzing electromagnetic wave propagation through the soil?

Accepted Answer

TDR/FDR sensor

Answer

Time Domain Reflectometry (TDR) and Frequency Domain Reflectometry (FDR) sensors determine volumetric water content by measuring how electromagnetic signals travel through soil.

Question 5

On the USDA soil texture triangle, a soil with 40% sand, 40% silt, and 20% clay is classified as:

Accepted Answer

Loam

Answer

A roughly balanced distribution of sand, silt, and moderate clay places this soil squarely in the loam category on the USDA texture triangle.

CIT - Certified Irrigation Technician Practice Test

CIT - Certified Irrigation Technician Practice Test

CIT Soil Science and Plant Water Requirements 2