All lines shall be plainly marked upon trees, and measured with chains.
Therefore, if a boundary line was marked by line trees and an original marked line tree is found, it still marks the boundary line (at least in alinement) and may become an angle point in the line.
Under the law, a definitely identified line tree is a monument of the original survey. As an existing monument, a line tree is used as a control point in the reestablishment of lost corners by the appropriate method of proportionate measurement.
Caution: Often line trees were recorded as being on the original surveyor’s random line and not on the actual true line between corners.
If a boundary line was marked with a blazed line by the original surveyor and can be definitely identified, the mean position of the blazed line still marks the boundary line and may be used to fix a meridional line for departure, or a latitudinal line for latitude in the absence of the original monuments.
Caution: Often the random lines were blazed rather than the actual true line between corners. Corrections may have been made by the original surveyor before the final acceptance of his survey or he may have blazed more than one line.