Apical Dominance – A condition where the terminal bud inhibits the growth and development of lateral buds on the same stem

Branch Bark Ridge – A raised line of bark that forms on the upper side of where the branch joins the trunk

D.B.H. (Diameter at Breast Height) – diameter outside the bark measured at breast height, 4.5 feet or 1.37m

Dominant – A tree branch or leader that exhibits strong apical control, resulting in an upright tree with a strong central leader

Co-Dominant – multiple leaders competing with each other

Included Bark – Bark that becomes embedded in a crotch between branch and trunk or between co-dominant stems, forming a weak union

Lateral Bud – Bud located on the side of a stem

Lion Tailing – Pruning that removes an excessive amount of interior branches, leaving only a few branches at the very end of a limb, displacing foliar weight to the end of branches.

Node – The slightly enlarged portion of a stem where leaves and buds emerge; the joint of a twig

Petiole – The stem of a leaf

Scaffold Branches – The permanent or structural branches of a tree

Terminal Bud – The bud located at the end of a twig or shoot

Wind-sail effect – The movement of air causing a limb to move and bend