a genarel rule is in the dormant peariod for most trees, you should not need anything bigger than a spade as the root system is not as invadish as most trees, be cairfull you do not plant it in heavy clay because it will not like it,

If you can lift it with as much damp soil as possible, now while the soil is still warm is a good time. Cut about a foot from the stem all lateral roots so that it will lift out in a big lump of soil. Some help will be useful.