Quotes utilised were taken from Modern Arboriculture,
by Alex L. Shigo

"Modern Arboriculture means...
1) The right tree in the right place
2) Building designs that give trees     space to grow
3) Beautiful trees growing in clusters
4) Healthy trees growing below grade
5) Young trees with space to grow
    and with proper early pruning
6) The target is removed not the tree
7) No sprouts from a correct pruning     cut
8) Early training regulates size and
    shape of trees
9) The sidewalk is cut,
    not the tree or it's roots

10) Proper care for old trees and
      respect for their dignity
11) Planting trees at the proper depth
12) People touching trees and       learning how they work, before       they work on them
13) Treatments that destroy defense
      systems must be stopped
14) Treatments that cause serious
       internal injuries must be        stopped
15) Treatments that start other
      problems must be stopped
16) Treatments that injure and kill
      transplanted trees must be       stopped"

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