Tree wrenching

Press, Volume CXV, Issue 33932, 27 August 1975, Page 14

Tree wrenching

Sir, — The wrenching of trees before planting has become a widespread habit. This promotes surface rooting and does away with the tap root which, reaching far into the ground, gave the tree stability, something which held the tree in the ground against buffeting winds. This is how I understand the picture. Could we have some expert opinions please? — Yours, etc., CANTERBURY’S FORESTS. August 13, 1975. [Mr J. W. Levy, Conservator of Forests, replies: “Your correspondent is correct in saying that wrenching has become a widespread habit. The purpose is to promote a growth of fibrous roots which will help the tree to establish itself quickly. The tap root would normally be destroyed in the process of lifting and planting in the forest in any case. It was very noticeable that even trees which had been grown naturally from seed in some forests were windthrown and close examination showed that they did not have large tap roots. It is considered to be better to plant out a tree which has a fibrous root sys-

tern which will put down large numbers of peg roots which will hold the tree firmly. If trees are too firmly rooted in the ground they will break in very high winds rather than uproot; this results in a smaller recovery of timber because of the shattering.”]