Increment borer – A hollow, auger-like instrument used to bore into the stem of a tree to remove a pencil-sized cylinder of wood containing a cross-section of the tree’s growth rings.
Insecticide – A chemical that kills insects.
Intermediate – See crown classification and shade tolerance.
Intermediate cut – The removal of physically or financially immature trees from a stand to improve the quality or growth of remaining trees. An intermediate cut may generate income (commercial cut) or may cost the forest landowner (a noncommercial cut). Contrast with harvest.