Photo 4.  Tree's are Rarely Round, so You Need to Take Two Diameter Measurements at 90 Degrees to Each Other.  Add the Two Measurements Together and Divide This Total by 2.  The Result will be the Average Diameter of the Tree.

excessive limbs, a major fork or other types of internal/external defects. Unless there are obvious, outward signs of defect in the trunk (logs), hardwood (deciduous or broadleaf) trees are normally measured to the first major fork in the trunk unless the upper (smaller) trunk diameter limit (determined by the processing mill) is reached before the fork in the trunk.  Larger limbs do not necessarily cause a problem if they do not create a "Y" fork in the trunk.  Side limbs will be cut off flush with the trunk when the tree is felled.  Limbs do, however, create knots, which are considered defects, so the quality of the wood will not be as good when the tree has many branches along the trunk.

Other types of defects in the trunk that affect a tree's merchantable height include crook or sweep (bend) in the trunk or outward signs of rot and decay such as a conk (fungus fruiting body), swelling or bulge on the side of the trunk, or a cavity hole (see photo 5, 5a, 5b, 5c, 5d, 5e, 5f on next page).  The cutoff (merchantable height) point will be at point below any of these defects for trees exhibiting such defects.

Conifers (evergreen, cone-bearing trees) normally grow with one central stem and rarely fork unless there is a double top.  Unless there are internal or external defects, merchantable height in conifers is frequently determined by the smaller