Question
We know fall is the time, ? is will it work to replant our 20 yr old blue spruce? 20' tall, 6' diameter. too close to the house, wish to move it IF it has a chance to live. how big of a spade might be needed? bobcat sized or truck mounted? lastly how big and deep of a hole?
Thanks!

Answer
You are on the top end of tree sizes that are required to be moved with a spade on a truck.  Here is a good PDF link that helps you plan for this challenge; The document is third PDF from the bottom ("Tree Transplanting with a Tree Spade")

http://www.destitotree.com/tree_articles.htm

This Mass.-based company homepage is really good, too, with lots of good info: www.destitotree.com

It is a function of the tree's trunk diameter, not canopy of evergreen's skirt spread.  You picked the right season for an evergreen, as long as you don't wait until it gets so cold that the ground freezes.

Tree-moving companies are probably busy this time of year, and I don't know how much they may charge you -- It is also regional, too.  We folks in the desert don't move that many trees so we get to pay more...

I have tried go on the "cheap" and move a large blue spruce a few years back for a church (about 20' tall), using a canvas sling and dug out with a backhoe --it died.  If you value the tree, it is worth it to hire a pro with a truck.

The hole size is a function of the tree spade.  The machine-operator will dig the receiving hole, first, then when they pick up the tree, the size matches (see the PDF for more info)

Check the yellow-pages for a tree-mover, or get a recommendation from a reputable local landscape contractor.

Hope it helps.   ~Marc