The Collaborative International Dictionary of English v.0.48:

Arboriculture \Ar`bor*i*cul"ture\ (?; 135), n. [L. arbor tree +
   cultura. See Culture.]
   The cultivation of trees and shrubs, chiefly for timber or
   for ornamental purposes.
   [1913 Webster]

WordNet (r) 3.0 (2006):

arboriculture
    n 1: the cultivation of tree for the production of timber [syn:
         arboriculture, tree farming]