frst 211 field quiz

how tall do u measure for a trees DBH

1.3 meters

on slopes where do u measure trees height for DBH

from high side

how to calc basal area from DBH?

Basal Area = pi(DBH/2)² = DBH cm²

• add all dbh together and divide by plot size for cm²/ha

how to measure height of tree using degrees

• use left side of clinometer (bigger spaces between numbers)

Height= HD x tan(angle 1) + HD x tan(angle 2) = height 0.1m

how to measure height of tree using percent

• use right side of clinometer (smaller spaces between numbers)

Height= HD x ((top angle - bottom angle)/100)

How to estimate basal area using a prism

1) use prism to determine trees in and out. if borderline look at limiting distance table using DBH and distance from plot center to determine

2) calc basal area based on # trees in and prisms BAF

ex) BAF 10 prism and 6 in trees = 6 × 10 = 60m²/ha

How to use compass to measure azimuth of an object

• point compass to object

• turn bezel til red in shed

• report azimuth at the top of the white arrow

How to use compass to orientate yourself to given azimuth

• level compass and rotate bezel to given azimuth

• rotate your body til red in shed then walk straight

how to calc pace factor

• get your paces per 100m

• foor example if you get 20 paces for 25 meters multiply by 4 to get per 100 meters

• then divide 100 by # of paces to get pace factor

How to estimate distance from your pace factor

• multiply your pace factor by number of paces for distance in meters

How to measure trees per hectar using basal area

• BAF (from prism) / that trees basal area (from DBH of selected trees)

• ex) you have 1 in tree with BAF 10 and basal area of .5 (must use DBH for BA)

• 10/ 0.5 = 20 trees / ha