CF Forest Resource Measurement and Inventory 2

Question 1

In a variable-radius plot using a 10-factor prism, a tree is counted if its DBH in inches is at least how many times the horizontal distance in feet from plot center?

Accepted Answer

DBH ≥ distance / 10

Answer

With a 10-BAF prism, a tree is tallied when DBH (inches) divided by horizontal distance (feet) equals or exceeds 1/10 (i.e., DBH ≥ distance/10 using the limiting distance formula).

Question 2

Which timber cruise method distributes sample points in a systematic grid pattern across the entire stand?

Accepted Answer

Systematic sampling

Answer

Systematic sampling places sample points at uniform intervals across a grid, ensuring even spatial coverage of the stand.

Question 3

The term 'merchantable height' in timber measurement refers to the length of the bole measured to:

Accepted Answer

The point where diameter inside bark reaches a minimum utilization standard

Answer

Merchantable height is the usable stem length up to the minimum top diameter inside bark acceptable for a given product standard.

Question 4

A stand has 80 trees per acre with an average basal area of 0.9 sq ft per tree. What is the stand basal area per acre?

Accepted Answer

72 sq ft

Answer

Stand basal area = trees per acre × average BA per tree = 80 × 0.9 = 72 sq ft per acre.

Question 5

Which of the following is the primary purpose of stratification in a forest inventory?

Accepted Answer

To reduce variance within groups and improve precision for a given sampling effort

Answer

Stratification groups similar units together, reducing within-stratum variance and increasing overall inventory precision without adding plots.

(CF) Certified Forester Exam Practice Test

(CF) Certified Forester Exam Practice Test

CF Forest Resource Measurement and Inventory 2