The Relascope is often used for point sampling. This is done by using the set spacing marked in the Relascope to gauge whether a tree is in or out of the stand. A tree is IN or OUT based on whether it fills the space between the lines on the scale in the Relascope. If it does then the tree is IN. If it doesn't then the tree is OUT. If the tree is IN this means that it is counted as basal area within one's plot. The basal area is obtained by multiplying the number of trees by the basal area factor, which is based on the width of the gauge.