Answer: Summer is the most difficult time for a dogwood to adjust to a new spot in the garden. It would be better to transplant it in late fall or in the very early spring while it is still dormant. Try not to damage the roots when you dig. I suspect most of the roots will be in the top 12-18 inches of soil and extend out as far as the tips of the branches. It's okay if you dig through some of the small feeder roots but try not to sever any of the main or major roots. If you dig slowly and carefully you should be able to keep most of the rootmass intact. Best wishes with your dogwood.
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