Spring is best but both will work...from what i have heard.

Early spring should be fine.

Late Fall.

I live in Atlanta but we have a radio show about planting any thing and everything.  He recommends early fall for planting trees.

I would think early Spring. 

I will look for the answers as I have no idea.

William... you are asking the wrong girl here! I'm from NYC and my attitude is that the best grass is green cement (LOL!)!

 Good morning William. I've always heard late fall.

Good morning William. Have always been told that the fall is the best, but wouldn't hesitate to plant in the spring as long as the watering in consistent.

In Washington State it is early Spring!

I would think early fall. That should give time for the roots to develop before the tree faces its first summer.

I've been told both seasons are good...at least in my area. 

In Northern Indiana we can plant trees all year.

Landscapers have always told me Fall.  Good news, since many sales are going on at that time!

I have always planted while the sap is down on the trees, which could be Spring or Fall.  This year I going to wait until the last frost is over, as I lost 2 new trees last year. Bob Crane is the man to ask!

I have lived in CT, NJ, and PA and the best time to plant trees in these states is in the early fall. In general, trees do better in cooler weather than baking in the hot summer sun.