Root Training/Development and Root Pruning

The following was distributed at the 1995 Menninger Sunbelt Tree Conference By Roy
A. Mecklenburg

Root Training/Development

• Circling/girdling roots can develop in a 2 inch seedling pot, 1 gallon, or 5 gallon
  container and prevent successful tree transplanting and establishment years
  later.
• If circling roots are not cut, roots will not move out of the root ball and the tree will
  blow down with every wind and will require constant irrigation within the root ball.
• In short it may never become fully established.
  The only cure is to cut the girdling roots which will be a severe shock to the tree.

Root Pruning 

• Every transplanting is in fact a root pruning, producing a more compact root
  system. Only a small percent of the root length of a nursery-grown tree is moved
  with the tree, but this small fraction of length represents 75% of the total root
  weight.
• Native, or collected trees, will benefit from root pruning, but it should be carried
  out one growing season before the final digging. The final root/soil ball should
  included one foot of new roots formed after root pruning.
• Trees can be balled and burlapped, wrapped in plastic and replanted in the same
  hole for a few months to harden off. During this time many fine roots develop
  making establishment in the final location quicker. This will also reduce
  transpiration during transporting the trees. All plastic covering must be removed
  at planting.