Planting a Tree

http://www.urbansustainableliving.com/how-to-plant-a-tree-the-right-way.html

I continue to disagree with the shallow hole method of tree planting.

The tree must be planted at the correct height in the hole, but I fail to see why the hole should be shallow.

A deeper hole encourages deeper rooting.

And as someone who has dug out a lot of tree roots, I know that trees grow deep roots if they can.