age class
a distinct aggregation of trees originating from a single natural event or regeneration activity; one of the intervals into which the age range of trees is divided for classification or use; a grouping of trees (e.g.

a ten-year age class) used in inventory or management

even-aged stand
a stand of trees composed of a single age-classin which the range of tree ages is usually within 20% of the rotation length
the act of renewing tree cover by establishing young trees naturally or artificially (note: regeneration usually maintains the same forest type and is done promptly after the previous stand or forest was removed)
the progeny that comprise a new age-class being established through an act of regeneration; may be true seedlings, seedling sprouts, stump sprouts, or root suckers
in even-aged silvicultural systems–The period between regeneration (establishment) of a stand and final harvest.
silvicultural method
a cutting procedure by which a new age class is created; major methods include: clearcutting, seed-tree, shelterwood, and selection
silvicultural system
a planned series of treatments for tending, harvesting, and re-establishing a stand (note: system is named for the regeneration method used)
two-aged stand
a stand with trees of two distinct age classes separated in age by mor than 20% of the rotation length
uneven-aged stand
a stand of trees with three or more distinct age classes either intimately mixed or in small groups
the establishment of a forest or stand in an area where the preceding vegetation or land use was not forest
the reestablishment of forest cover either naturally (by natural seeding, coppice, or root suckers) or artificially (by direct seeding, or planting)–note: reforestation usually maintains the same forest type and is done promptly after the previous stand was removed